["[Dialogue between User and Assistant on 2024-01-01 00:00]\n<User>Let me share some additional facts I found:\nFrom the mid-1950s through the 1960s, in the U.S. the common home record player or \"stereo\" (after the introduction of stereo recording) would typically have had these features: a three- or four-speed player (78, 45, 33 1\u20443, and sometimes 16 2\u20443 rpm); with changer, a tall spindle that would hold several records and automatically drop a new record on top of the previous one when it had finished playing, a combination cartridge with both 78 and microgroove styli and a way to flip between the two; and some kind of adapter for playing the 45s with their larger center hole. The adapter could be a small solid circle that fit onto the bottom of the spindle (meaning only one 45 could be played at a time) or a larger adaptor that fit over the entire spindle, permitting a stack of 45s to be played.\n\nRCA 45s were also adapted to the smaller spindle of an LP player with a plastic snap-in insert known as a \"spider\". These inserts, commissioned by RCA president David Sarnoff and invented by Thomas Hutchison, were prevalent starting in the 1960s, selling in the tens of millions per year during the 45 rpm heyday. In countries outside the U.S., 45s often had the smaller album-sized holes, e.g., Australia and New Zealand, or as in the United Kingdom, especially before the 1970s, the disc had a small hole within a circular central section held only by three or four lands so that it could be easily punched out if desired (typically for use in jukeboxes).\n\nThe term \"high fidelity\" was coined in the 1920s by some manufacturers of radio receivers and phonographs to differentiate their better-sounding products claimed as providing \"perfect\" sound reproduction. The term began to be used by some audio engineers and consumers through the 1930s and 1940s. After 1949 a variety of improvements in recording and playback technologies, especially stereo recordings, which became widely available in 1958, gave a boost to the \"hi-fi\" classification of products, leading to sales of individual components for the home such as amplifiers, loudspeakers, phonographs, and tape players. High Fidelity and Audio were two magazines that hi-fi consumers and engineers could read for reviews of playback equipment and recordings.\n\nStereophonic sound recording, which attempts to provide a more natural listening experience by reproducing the spatial locations of sound sources in the horizontal plane, was the natural extension to monophonic recording, and attracted various alternative engineering attempts. The ultimately dominant \"45/45\" stereophonic record system was invented by Alan Blumlein of EMI in 1931 and patented the same year. EMI cut the first stereo test discs using the system in 1933 (see Bell Labs Stereo Experiments of 1933) although the system was not exploited commercially until much later.\n\nThe development of quadraphonic records was announced in 1971. These recorded four separate sound signals. This was achieved on the two stereo channels by electronic matrixing, where the additional channels were combined into the main signal. When the records were played, phase-detection circuits in the amplifiers were able to decode the signals into four separate channels. There were two main systems of matrixed quadraphonic records produced, confusingly named SQ (by CBS) and QS (by Sansui). They proved commercially unsuccessful, but were an important precursor to later surround-sound systems, as seen in SACD and home cinema today.\n\nA different format, CD-4 (not to be confused with compact disc), by RCA, encoded the front-rear difference information on an ultrasonic carrier, which required a special wideband cartridge to capture it on carefully calibrated pickup arm/turntable combinations. CD-4 was even less successful than the two matrixed formats. (A further problem was that no cutting heads were available that could handle the HF information. That was remedied by cutting at half the speed. Later, the special half-speed cutting heads and equalization techniques were employed to get a wider frequency response in stereo with reduced distortion and greater headroom.)\n\nUnder the direction of recording engineer C. Robert Fine, Mercury Records initiated a minimalist single microphone monaural recording technique in 1951. The first record, a Chicago Symphony Orchestra performance of Pictures at an Exhibition, conducted by Rafael Kubelik, was described as \"being in the living presence of the orchestra\" by The New York Times music critic. The series of records was then named Mercury Living Presence. In 1955, Mercury began three-channel stereo recordings, still based on the principle of the single microphone. The center (single) microphone was of paramount importance, with the two side mics adding depth and space. Record masters were cut directly from a three-track to two-track mixdown console, with all editing of the master tapes done on the original three-tracks. In 1961, Mercury enhanced this technique with three-microphone stereo recordings using 35 mm magnetic film instead of half-inch tape for recording. The greater thickness and width of 35 mm magnetic film prevented tape layer print-through and pre-echo and gained extended frequency range and transient response. The Mercury Living Presence recordings were remastered to CD in the 1990s by the original producer, Wilma Cozart Fine, using the same method of 3-to-2 mix directly to the master recorder.\n<Assistant>Got it. I will remember them.", "[Dialogue between User and Assistant on 2024-01-02 00:00]\n<User>I have some fresh insights to share:\nThrough the 1960s, 1970s, and 1980s, various methods to improve the dynamic range of mass-produced records involved highly advanced disc cutting equipment. These techniques, marketed, to name two, as the CBS DisComputer and Teldec Direct Metal Mastering, were used to reduce inner-groove distortion. RCA Victor introduced another system to reduce dynamic range and achieve a groove with less surface noise under the commercial name of Dynagroove. Two main elements were combined: another disk material with less surface noise in the groove and dynamic compression for masking background noise. Sometimes this was called \"diaphragming\" the source material and not favoured by some music lovers for its unnatural side effects. Both elements were reflected in the brandname of Dynagroove, described elsewhere in more detail. It also used the earlier advanced method of forward-looking control on groove spacing with respect to volume of sound and position on the disk. Lower recorded volume used closer spacing; higher recorded volume used wider spacing, especially with lower frequencies. Also, the higher track density at lower volumes enabled disk recordings to end farther away from the disk center than usual, helping to reduce endtrack distortion even further.\n\nAlso in the late 1970s, \"direct-to-disc\" records were produced, aimed at an audiophile niche market. These completely bypassed the use of magnetic tape in favor of a \"purist\" transcription directly to the master lacquer disc. Also during this period, half-speed mastered and \"original master\" records were released, using expensive state-of-the-art technology. A further late 1970s development was the Disco Eye-Cued system used mainly on Motown 12-inch singles released between 1978 and 1980. The introduction, drum-breaks, or choruses of a track were indicated by widely separated grooves, giving a visual cue to DJs mixing the records. The appearance of these records is similar to an LP, but they only contain one track each side.\n\nThe mid-1970s saw the introduction of dbx-encoded records, again for the audiophile niche market. These were completely incompatible with standard record playback preamplifiers, relying on the dbx compandor encoding/decoding scheme to greatly increase dynamic range (dbx encoded disks were recorded with the dynamic range compressed by a factor of two in dB: quiet sounds were meant to be played back at low gain and loud sounds were meant to be played back at high gain, via automatic gain control in the playback equipment; this reduced the effect of surface noise on quiet passages). A similar and very short-lived scheme involved using the CBS-developed \"CX\" noise reduction encoding/decoding scheme.\n<Assistant>Appreciated. I'll retain these important details.", "[Dialogue between User and Assistant on 2024-01-03 00:00]\n<User>I have some interesting updates for you:\nELPJ, a Japanese-based company, sells a laser turntable that uses a laser to read vinyl discs optically, without physical contact. The laser turntable eliminates record wear and the possibility of accidental scratches, which degrade the sound, but its expense limits use primarily to digital archiving of analog records, and the laser does not play back colored vinyl or picture discs. Various other laser-based turntables were tried during the 1990s, but while a laser reads the groove very accurately, since it does not touch the record, the dust that vinyl attracts due to static electric charge is not mechanically pushed out of the groove, worsening sound quality in casual use compared to conventional stylus playback.\n\nIn some ways similar to the laser turntable is the IRENE scanning machine for disc records, which images with microphotography in two dimensions, invented by a team of physicists at Lawrence Berkeley Laboratories. IRENE will retrieve the information from a laterally modulated monaural grooved sound source without touching the medium itself, but cannot read vertically modulated information. This excludes grooved recordings such as cylinders and some radio transcriptions that feature a hill-and-dale format of recording, and stereophonic or quadraphonic grooved recordings, which utilize a combination of the two as well as supersonic encoding for quadraphonic.\n<Assistant>Thank you for sharing. I've noted this information.", "[Dialogue between User and Assistant on 2024-01-04 00:00]\n<User>Here are some new facts I learnt just now:\nTerms such as \"long-play\" (LP) and \"extended-play\" (EP) describe multi-track records that play much longer than the single-item-per-side records, which typically do not go much past four minutes per side. An LP can play for up to 30 minutes per side, though most played for about 22 minutes per side, bringing the total playing time of a typical LP recording to about forty-five minutes. Many pre-1952 LPs, however, played for about 15 minutes per side. The 7-inch 45 rpm format normally contains one item per side but a 7-inch EP could achieve recording times of 10 to 15 minutes at the expense of attenuating and compressing the sound to reduce the width required by the groove. EP discs were generally used to make available tracks not on singles including tracks on LPs albums in a smaller, less expensive format for those who had only 45 rpm players. The large center hole on 7-inch 45 rpm records allows for easier handling by jukebox mechanisms. The term \"album\", originally used to mean a \"book\" with liner notes, holding several 78 rpm records each in its own \"page\" or sleeve, no longer has any relation to the physical format: a single LP record, or nowadays more typically a compact disc.\n\nIn March 1949, as RCA released the 45, Columbia released several hundred 7 inch 33 1/3 rpm small spindle hole singles. This format was soon dropped as it became clear that the RCA 45 was the single of choice and the Columbia 12 inch LP would be the 'album' of choice. The first release of the 45 came in seven colors: black 47-xxxx popular series, yellow 47-xxxx juvenile series, green (teal) 48-xxxx country series, deep red 49-xxxx classical series, bright red (cerise) 50-xxxx blues/spiritual series, light blue 51-xxxx international series, dark blue 52-xxxx light classics. All colors were soon dropped in favor of black because of production problems. However, yellow and deep red were continued until about 1952. The first 45 rpm record created for sale was \"PeeWee the Piccolo\" RCA 47-0147 pressed in yellow translucent vinyl at the Sherman Avenue plant, Indianapolis Dec. 7, 1948, R.O. Price, plant manager.\n\nThe normal commercial disc is engraved with two sound-bearing concentric spiral grooves, one on each side, running from the outside edge towards the center. The last part of the spiral meets an earlier part to form a circle. The sound is encoded by fine variations in the edges of the groove that cause a stylus (needle) placed in it to vibrate at acoustic frequencies when the disc is rotated at the correct speed. Generally, the outer and inner parts of the groove bear no intended sound (an exception is Split Enz's Mental Notes).\n\nTowards the center, at the end of the groove, there is another wide-pitched section known as the lead-out. At the very end of this section the groove joins itself to form a complete circle, called the lock groove; when the stylus reaches this point, it circles repeatedly until lifted from the record. On some recordings (for example Sgt. Pepper's Lonely Hearts Club Band by The Beatles, Super Trouper by Abba and Atom Heart Mother by Pink Floyd), the sound continues on the lock groove, which gives a strange repeating effect. Automatic turntables rely on the position or angular velocity of the arm, as it reaches the wider spacing in the groove, to trigger a mechanism that lifts the arm off the record. Precisely because of this mechanism, most automatic turntables are incapable of playing any audio in the lock groove, since they will lift the arm before it reaches that groove.\n\nWhen auto-changing turntables were commonplace, records were typically pressed with a raised (or ridged) outer edge and a raised label area, allowing records to be stacked onto each other without the delicate grooves coming into contact, reducing the risk of damage. Auto-changers included a mechanism to support a stack of several records above the turntable itself, dropping them one at a time onto the active turntable to be played in order. Many longer sound recordings, such as complete operas, were interleaved across several 10-inch or 12-inch discs for use with auto-changing mechanisms, so that the first disk of a three-disk recording would carry sides 1 and 6 of the program, while the second disk would carry sides 2 and 5, and the third, sides 3 and 4, allowing sides 1, 2, and 3 to be played automatically; then the whole stack reversed to play sides 4, 5, and 6.\n\nNew or \"virgin\" heavy/heavyweight (180\u2013220 g) vinyl is commonly used for modern audiophile vinyl releases in all genres. Many collectors prefer to have heavyweight vinyl albums, which have been reported to have better sound than normal vinyl because of their higher tolerance against deformation caused by normal play. 180 g vinyl is more expensive to produce only because it uses more vinyl. Manufacturing processes are identical regardless of weight. In fact, pressing lightweight records requires more care. An exception is the propensity of 200 g pressings to be slightly more prone to non-fill, when the vinyl biscuit does not sufficiently fill a deep groove during pressing (percussion or vocal amplitude changes are the usual locations of these artifacts). This flaw causes a grinding or scratching sound at the non-fill point.\n<Assistant>Got it. I will remember them.", "[Dialogue between User and Assistant on 2024-01-05 00:00]\n<User>The following are some more news I learnt:\nThe \"orange peel\" effect on vinyl records is caused by worn molds. Rather than having the proper mirror-like finish, the surface of the record will have a texture that looks like orange peel. This introduces noise into the record, particularly in the lower frequency range. With direct metal mastering (DMM), the master disc is cut on a copper-coated disc, which can also have a minor \"orange peel\" effect on the disc itself. As this \"orange peel\" originates in the master rather than being introduced in the pressing stage, there is no ill effect as there is no physical distortion of the groove.\n<Assistant>Great! I've added this to my knowledge base.", "[Dialogue between User and Assistant on 2024-01-06 00:00]\n<User>I have some fresh insights to share:\nOriginal master discs are created by lathe-cutting: a lathe is used to cut a modulated groove into a blank record. The blank records for cutting used to be cooked up, as needed, by the cutting engineer, using what Robert K. Morrison describes as a \"metallic soap,\" containing lead litharge, ozokerite, barium sulfate, montan wax, stearin and paraffin, among other ingredients. Cut \"wax\" sound discs would be placed in a vacuum chamber and gold-sputtered to make them electrically conductive for use as mandrels in an electroforming bath, where pressing stamper parts were made. Later, the French company Pyral invented a ready-made blank disc having a thin nitro-cellulose lacquer coating (approximately 7 mils thickness on both sides) that was applied to an aluminum substrate. Lacquer cuts result in an immediately playable, or processable, master record. If vinyl pressings are wanted, the still-unplayed sound disc is used as a mandrel for electroforming nickel records that are used for manufacturing pressing stampers. The electroformed nickel records are mechanically separated from their respective mandrels. This is done with relative ease because no actual \"plating\" of the mandrel occurs in the type of electrodeposition known as electroforming, unlike with electroplating, in which the adhesion of the new phase of metal is chemical and relatively permanent. The one-molecule-thick coating of silver (that was sprayed onto the processed lacquer sound disc in order to make its surface electrically conductive) reverse-plates onto the nickel record's face. This negative impression disc (having ridges in place of grooves) is known as a nickel master, \"matrix\" or \"father.\" The \"father\" is then used as a mandrel to electroform a positive disc known as a \"mother\". Many mothers can be grown on a single \"father\" before ridges deteriorate beyond effective use. The \"mothers\" are then used as mandrels for electroforming more negative discs known as \"sons\". Each \"mother\" can be used to make many \"sons\" before deteriorating. The \"sons\" are then converted into \"stampers\" by center-punching a spindle hole (which was lost from the lacquer sound disc during initial electroforming of the \"father\"), and by custom-forming the target pressing profile. This allows them to be placed in the dies of the target (make and model) record press and, by center-roughing, to facilitate the adhesion of the label, which gets stuck onto the vinyl pressing without any glue. In this way, several million vinyl discs can be produced from a single lacquer sound disc. When only a few hundred discs are required, instead of electroforming a \"son\" (for each side), the \"father\" is removed of its silver and converted into a stamper. Production by this latter method, known as the \"two-step-process\" (as it does not entail creation of \"sons\" but does involve creation of \"mothers,\" which are used for test playing and kept as \"safeties\" for electroforming future \"sons\") is limited to a few hundred vinyl pressings. The pressing count can increase if the stamper holds out and the quality of the vinyl is high. The \"sons\" made during a \"three-step\" electroforming make better stampers since they don't require silver removal (which reduces some high fidelity because of etching erasing part of the smallest groove modulations) and also because they have a stronger metal structure than \"fathers\".\n\nBreakage was very common in the shellac era. In the 1934 John O'Hara novel, Appointment in Samarra, the protagonist \"broke one of his most favorites, Whiteman's Lady of the Evening ... He wanted to cry but could not.\" A poignant moment in J. D. Salinger's 1951 novel The Catcher in the Rye occurs after the adolescent protagonist buys a record for his younger sister but drops it and \"it broke into pieces ... I damn-near cried, it made me feel so terrible.\" A sequence where a school teacher's collection of 78 rpm jazz records is smashed by a group of rebellious students is a key moment in the film Blackboard Jungle.\n\nVinyl records do not break easily, but the soft material is easily scratched. Vinyl readily acquires a static charge, attracting dust that is difficult to remove completely. Dust and scratches cause audio clicks and pops. In extreme cases, they can cause the needle to skip over a series of grooves, or worse yet, cause the needle to skip backwards, creating a \"locked groove\" that repeats over and over. This is the origin of the phrase \"like a broken record\" or \"like a scratched record\", which is often used to describe a person or thing that continually repeats itself. Locked grooves are not uncommon and were even heard occasionally in radio broadcasts.\n\nVinyl records can be warped by heat, improper storage, exposure to sunlight, or manufacturing defects such as excessively tight plastic shrinkwrap on the album cover. A small degree of warp was common, and allowing for it was part of the art of turntable and tonearm design. \"wow\" (once-per-revolution pitch variation) could result from warp, or from a spindle hole that was not precisely centered. Standard practice for LPs was to place the LP in a paper or plastic inner cover. This, if placed within the outer cardboard cover so that the opening was entirely within the outer cover, was said to reduce ingress of dust onto the record surface. Singles, with rare exceptions, had simple paper covers with no inner cover.\n\nA further limitation of the gramophone record is that fidelity steadily declines as playback progresses; there is more vinyl per second available for fine reproduction of high frequencies at the large-diameter beginning of the groove than exist at the smaller-diameters close to the end of the side. At the start of a groove on an LP there are 510 mm of vinyl per second traveling past the stylus while the ending of the groove gives 200\u2013210 mm of vinyl per second \u2014 less than half the linear resolution. Distortion towards the end of the side is likely to become more apparent as record wear increases.*\n\nTonearm skating forces and other perturbations are also picked up by the stylus. This is a form of frequency multiplexing as the control signal (restoring force) used to keep the stylus in the groove is carried by the same mechanism as the sound itself. Subsonic frequencies below about 20 Hz in the audio signal are dominated by tracking effects, which is one form of unwanted rumble (\"tracking noise\") and merges with audible frequencies in the deep bass range up to about 100 Hz. High fidelity sound equipment can reproduce tracking noise and rumble. During a quiet passage, woofer speaker cones can sometimes be seen to vibrate with the subsonic tracking of the stylus, at frequencies as low as just above 0.5 Hz (the frequency at which a 33 1\u20443 rpm record turns on the turntable; 5\u20449 Hz exactly on an ideal turntable). Another reason for very low frequency material can be a warped disk: its undulations produce frequencies of only a few hertz and present day amplifiers have large power bandwidths. For this reason, many stereo receivers contained a switchable subsonic filter. Some subsonic content is directly out of phase in each channel. If played back on a mono subwoofer system, the noise will cancel, significantly reducing the amount of rumble that is reproduced.\n\nDue to recording mastering and manufacturing limitations, both high and low frequencies were removed from the first recorded signals by various formulae. With low frequencies, the stylus must swing a long way from side to side, requiring the groove to be wide, taking up more space and limiting the playing time of the record. At high frequencies, hiss, pops, and ticks are significant. These problems can be reduced by using equalization to an agreed standard. During recording the amplitude of low frequencies is reduced, thus reducing the groove width required, and the amplitude at high frequencies is increased. The playback equipment boosts bass and cuts treble so as to restore the tonal balance in the original signal; this also reduces the high frequency noise. Thus more music will fit on the record, and noise is reduced.\n<Assistant>Received. I'll store this information.", "[Dialogue between User and Assistant on 2024-01-07 00:00]\n<User>I have some interesting updates for you:\nIn 1926 Joseph P. Maxwell and Henry C. Harrison from Bell Telephone Laboratories disclosed that the recording pattern of the Western Electric \"rubber line\" magnetic disc cutter had a constant velocity characteristic. This meant that as frequency increased in the treble, recording amplitude decreased. Conversely, in the bass as frequency decreased, recording amplitude increased. Therefore, it was necessary to attenuate the bass frequencies below about 250 Hz, the bass turnover point, in the amplified microphone signal fed to the recording head. Otherwise, bass modulation became excessive and overcutting took place into the next record groove. When played back electrically with a magnetic pickup having a smooth response in the bass region, a complementary boost in amplitude at the bass turnover point was necessary. G. H. Miller in 1934 reported that when complementary boost at the turnover point was used in radio broadcasts of records, the reproduction was more realistic and many of the musical instruments stood out in their true form.\n\nWest in 1930 and later P. G. A. H. Voigt (1940) showed that the early Wente-style condenser microphones contributed to a 4 to 6 dB midrange brilliance or pre-emphasis in the recording chain. This meant that the electrical recording characteristics of Western Electric licensees such as Columbia Records and Victor Talking Machine Company in the 1925 era had a higher amplitude in the midrange region. Brilliance such as this compensated for dullness in many early magnetic pickups having drooping midrange and treble response. As a result, this practice was the empirical beginning of using pre-emphasis above 1,000 Hz in 78 rpm and 33 1\u20443 rpm records.\n\nOver the years a variety of record equalization practices emerged and there was no industry standard. For example, in Europe recordings for years required playback with a bass turnover setting of 250\u2013300 Hz and a treble roll-off at 10,000 Hz ranging from 0 to \u22125 dB or more. In the US there were more varied practices and a tendency to use higher bass turnover frequencies such as 500 Hz as well as a greater treble rolloff like \u22128.5 dB and even more to record generally higher modulation levels on the record.\n\nEvidence from the early technical literature concerning electrical recording suggests that it wasn't until the 1942\u20131949 period that there were serious efforts to standardize recording characteristics within an industry. Heretofore, electrical recording technology from company to company was considered a proprietary art all the way back to the 1925 Western Electric licensed method used by Columbia and Victor. For example, what Brunswick-Balke-Collender (Brunswick Corporation) did was different from the practices of Victor.\n\nBroadcasters were faced with having to adapt daily to the varied recording characteristics of many sources: various makers of \"home recordings\" readily available to the public, European recordings, lateral-cut transcriptions, and vertical-cut transcriptions. Efforts were started in 1942 to standardize within the National Association of Broadcasters (NAB), later known as the National Association of Radio and Television Broadcasters (NARTB). The NAB, among other items, issued recording standards in 1949 for laterally and vertically cut records, principally transcriptions. A number of 78 rpm record producers as well as early LP makers also cut their records to the NAB/NARTB lateral standard.\n\nThe lateral cut NAB curve was remarkably similar to the NBC Orthacoustic curve that evolved from practices within the National Broadcasting Company since the mid-1930s. Empirically, and not by any formula, it was learned that the bass end of the audio spectrum below 100 Hz could be boosted somewhat to override system hum and turntable rumble noises. Likewise at the treble end beginning at 1,000 Hz, if audio frequencies were boosted by 16 dB at 10,000 Hz the delicate sibilant sounds of speech and high overtones of musical instruments could survive the noise level of cellulose acetate, lacquer/aluminum, and vinyl disc media. When the record was played back using a complementary inverse curve, signal-to-noise ratio was improved and the programming sounded more lifelike.\n\nUltimately, the New Orthophonic curve was disclosed in a publication by R.C. Moyer of RCA Victor in 1953. He traced RCA Victor characteristics back to the Western Electric \"rubber line\" recorder in 1925 up to the early 1950s laying claim to long-held recording practices and reasons for major changes in the intervening years. The RCA Victor New Orthophonic curve was within the tolerances for the NAB/NARTB, Columbia LP, and AES curves. It eventually became the technical predecessor to the RIAA curve.\n\nDelicate sounds and fine overtones were mostly lost, because it took a lot of sound energy to vibrate the recording horn diaphragm and cutting mechanism. There were acoustic limitations due to mechanical resonances in both the recording and playback system. Some pictures of acoustic recording sessions show horns wrapped with tape to help mute these resonances. Even an acoustic recording played back electrically on modern equipment sounds like it was recorded through a horn, notwithstanding a reduction in distortion because of the modern playback. Toward the end of the acoustic era, there were many fine examples of recordings made with horns.\n\nElectric recording which developed during the time that early radio was becoming popular (1925) benefited from the microphones and amplifiers used in radio studios. The early electric recordings were reminiscent tonally of acoustic recordings, except there was more recorded bass and treble as well as delicate sounds and overtones cut on the records. This was in spite of some carbon microphones used, which had resonances that colored the recorded tone. The double button carbon microphone with stretched diaphragm was a marked improvement. Alternatively, the Wente style condenser microphone used with the Western Electric licensed recording method had a brilliant midrange and was prone to overloading from sibilants in speech, but generally it gave more accurate reproduction than carbon microphones.\n\nIt was not unusual for electric recordings to be played back on acoustic phonographs. The Victor Orthophonic phonograph was a prime example where such playback was expected. In the Orthophonic, which benefited from telephone research, the mechanical pickup head was redesigned with lower resonance than the traditional mica type. Also, a folded horn with an exponential taper was constructed inside the cabinet to provide better impedance matching to the air. As a result, playback of an Orthophonic record sounded like it was coming from a radio.\n\nEventually, when it was more common for electric recordings to be played back electrically in the 1930s and 1940s, the overall tone was much like listening to a radio of the era. Magnetic pickups became more common and were better designed as time went on, making it possible to improve the damping of spurious resonances. Crystal pickups were also introduced as lower cost alternatives. The dynamic or moving coil microphone was introduced around 1930 and the velocity or ribbon microphone in 1932. Both of these high quality microphones became widespread in motion picture, radio, recording, and public address applications.\n\nOver time, fidelity, dynamic and noise levels improved to the point that it was harder to tell the difference between a live performance in the studio and the recorded version. This was especially true after the invention of the variable reluctance magnetic pickup cartridge by General Electric in the 1940s when high quality cuts were played on well-designed audio systems. The Capehart radio/phonographs of the era with large diameter electrodynamic loudspeakers, though not ideal, demonstrated this quite well with \"home recordings\" readily available in the music stores for the public to buy.\n\nThere were important quality advances in recordings specifically made for radio broadcast. In the early 1930s Bell Telephone Laboratories and Western Electric announced the total reinvention of disc recording: the Western Electric Wide Range System, \"The New Voice of Action\". The intent of the new Western Electric system was to improve the overall quality of disc recording and playback. The recording speed was 33 1\u20443 rpm, originally used in the Western Electric/ERPI movie audio disc system implemented in the early Warner Brothers' Vitaphone \"talkies\" of 1927.\n\nThe newly invented Western Electric moving coil or dynamic microphone was part of the Wide Range System. It had a flatter audio response than the old style Wente condenser type and didn't require electronics installed in the microphone housing. Signals fed to the cutting head were pre-emphasized in the treble region to help override noise in playback. Groove cuts in the vertical plane were employed rather than the usual lateral cuts. The chief advantage claimed was more grooves per inch that could be crowded together, resulting in longer playback time. Additionally, the problem of inner groove distortion, which plagued lateral cuts, could be avoided with the vertical cut system. Wax masters were made by flowing heated wax over a hot metal disc thus avoiding the microscopic irregularities of cast blocks of wax and the necessity of planing and polishing.\n<Assistant>Received. I'll store this information.", "[Dialogue between User and Assistant on 2024-01-08 00:00]\n<User>I've gathered some additional data to share:\nVinyl pressings were made with stampers from master cuts that were electroplated in vacuo by means of gold sputtering. Audio response was claimed out to 8,000 Hz, later 13,000 Hz, using light weight pickups employing jeweled styli. Amplifiers and cutters both using negative feedback were employed thereby improving the range of frequencies cut and lowering distortion levels. Radio transcription producers such as World Broadcasting System and Associated Music Publishers (AMP) were the dominant licensees of the Western Electric wide range system and towards the end of the 1930s were responsible for two-thirds of the total radio transcription business. These recordings use a bass turnover of 300 Hz and a 10,000 Hz rolloff of \u22128.5 dB.\n\nThe complete technical disclosure of the Columbia LP by Peter C. Goldmark, Rene' Snepvangers and William S. Bachman in 1949 made it possible for a great variety of record companies to get into the business of making long playing records. The business grew quickly and interest spread in high fidelity sound and the do-it-yourself market for pickups, turntables, amplifier kits, loudspeaker enclosure plans, and AM/FM radio tuners. The LP record for longer works, 45 rpm for pop music, and FM radio became high fidelity program sources in demand. Radio listeners heard recordings broadcast and this in turn generated more record sales. The industry flourished.\n\nThere is a theory that vinyl records can audibly represent higher frequencies than compact discs. According to Red Book specifications, the compact disc has a frequency response of 20 Hz up to 22,050 Hz, and most CD players measure flat within a fraction of a decibel from at least 20 Hz to 20 kHz at full output. Turntable rumble obscures the low-end limit of vinyl but the upper end can be, with some cartridges, reasonably flat within a few decibels to 30 kHz, with gentle roll-off. Carrier signals of Quad LPs popular in the 1970s were at 30 kHz to be out of the range of human hearing. The average human auditory system is sensitive to frequencies from 20 Hz to a maximum of around 20,000 Hz. The upper and lower frequency limits of human hearing vary per person.\n\nFor the first several decades of disc record manufacturing, sound was recorded directly on to the \"master disc\" at the recording studio. From about 1950 on (earlier for some large record companies, later for some small ones) it became usual to have the performance first recorded on audio tape, which could then be processed and/or edited, and then dubbed on to the master disc. A record cutter would engrave the grooves into the master disc. Early versions of these master discs were soft wax, and later a harder lacquer was used. The mastering process was originally something of an art as the operator had to manually allow for the changes in sound which affected how wide the space for the groove needed to be on each rotation.\n\nAs the playing of gramophone records causes gradual degradation of the recording, they are best preserved by transferring them onto other media and playing the records as rarely as possible. They need to be stored on edge, and do best under environmental conditions that most humans would find comfortable. The medium needs to be kept clean, but alcohol should only be used on PVC or optical media, not on 78s.[citation needed] The equipment for playback of certain formats (e.g., 16 and 78 rpm) is manufactured only in small quantities, leading to increased difficulty in finding equipment to play the recordings.\n\nWhere old disc recordings are considered to be of artistic or historic interest, from before the era of tape or where no tape master exists, archivists play back the disc on suitable equipment and record the result, typically onto a digital format, which can be copied and manipulated to remove analog flaws without any further damage to the source recording. For example, Nimbus Records uses a specially built horn record player to transfer 78s. Anyone can do this using a standard record player with a suitable pickup, a phono-preamp (pre-amplifier) and a typical personal computer. However, for accurate transfer, professional archivists carefully choose the correct stylus shape and diameter, tracking weight, equalisation curve and other playback parameters and use high-quality analogue-to-digital converters.\n<Assistant>Understood. I'll keep these facts for future reference.", "[Dialogue between User and Assistant on 2024-01-09 00:00]\n<User>Let me tell you about some new developments:\nGroove recordings, first designed in the final quarter of the 19th century, held a predominant position for nearly a century\u2014withstanding competition from reel-to-reel tape, the 8-track cartridge, and the compact cassette. In 1988, the compact disc surpassed the gramophone record in unit sales. Vinyl records experienced a sudden decline in popularity between 1988 and 1991, when the major label distributors restricted their return policies, which retailers had been relying on to maintain and swap out stocks of relatively unpopular titles. First the distributors began charging retailers more for new product if they returned unsold vinyl, and then they stopped providing any credit at all for returns. Retailers, fearing they would be stuck with anything they ordered, only ordered proven, popular titles that they knew would sell, and devoted more shelf space to CDs and cassettes. Record companies also deleted many vinyl titles from production and distribution, further undermining the availability of the format and leading to the closure of pressing plants. This rapid decline in the availability of records accelerated the format's decline in popularity, and is seen by some as a deliberate ploy to make consumers switch to CDs, which were more profitable for the record companies.\n\nIn spite of their flaws, such as the lack of portability, records still have enthusiastic supporters. Vinyl records continue to be manufactured and sold today, especially by independent rock bands and labels, although record sales are considered to be a niche market composed of audiophiles, collectors, and DJs. Old records and out-of-print recordings in particular are in much demand by collectors the world over. (See Record collecting.) Many popular new albums are given releases on vinyl records and older albums are also given reissues, sometimes on audiophile-grade vinyl.\n\nMany electronic dance music and hip hop releases today are still preferred on vinyl; however, digital copies are still widely available. This is because for disc jockeys (\"DJs\"), vinyl has an advantage over the CD: direct manipulation of the medium. DJ techniques such as slip-cueing, beatmatching, and scratching originated on turntables. With CDs or compact audio cassettes one normally has only indirect manipulation options, e.g., the play, stop, and pause buttons. With a record one can place the stylus a few grooves farther in or out, accelerate or decelerate the turntable, or even reverse its direction, provided the stylus, record player, and record itself are built to withstand it. However, many CDJ and DJ advances, such as DJ software and time-encoded vinyl, now have these capabilities and more.\n\nIn 2014 artist Jack White sold 40,000 copies of his second solo release, Lazaretto, on vinyl. The sales of the record beat the largest sales in one week on vinyl since 1991. The sales record was previously held by Pearl Jam's, Vitalogy, which sold 34,000 copies in one week in 1994. In 2014, the sale of vinyl records was the only physical music medium with increasing sales with relation to the previous year. Sales of other mediums including individual digital tracks, digital albums and compact discs have fallen, the latter having the greatest drop-in-sales rate.\n\nHistorically, the channel's programming consisted mainly of featured classic theatrically released feature films from the Turner Entertainment film library \u2013 which comprises films from Warner Bros. Pictures (covering films released before 1950) and Metro-Goldwyn-Mayer (covering films released before May 1986). However, TCM now has licensing deals with other Hollywood film studios as well as its Time Warner sister company, Warner Bros. (which now controls the Turner Entertainment library and its own later films), and occasionally shows more recent films. Turner Classic Movies is a dedicated film channel and is available in United States, United Kingdom, France (TCM Cin\u00e9ma), Spain (TCM Espa\u00f1a), Nordic countries, Middle East and Africa.\n\nIn 1986, eight years before the launch of Turner Classic Movies, Ted Turner acquired the Metro-Goldwyn-Mayer film studio for $1.5 billion. Concerns over Turner Entertainment's corporate debt load resulted in Turner selling the studio that October back to Kirk Kerkorian, from whom Turner had purchased the studio less than a year before. As part of the deal, Turner Entertainment retained ownership of MGM's library of films released up to May 9, 1986. Turner Broadcasting System was split into two companies; Turner Broadcasting System and Metro-Goldwyn-Mayer and reincorporated as MGM/UA Communications Co.\n\nThe film library of Turner Entertainment would serve as the base form of programming for TCM upon the network's launch. Before the creation of Turner Classic Movies, films from Turner's library of movies aired on the Turner Broadcasting System's advertiser-supported cable network TNT \u2013 along with colorized versions of black-and-white classics such as The Maltese Falcon. After the library was acquired, MGM/UA signed a deal with Turner to continue distributing the pre-May 1986 MGM and to begin distributing the pre-1950 Warner Bros. film libraries for video release (the rest of the library went to Turner Home Entertainment).\n\nAt the time of its launch, TCM was available to approximately one million cable television subscribers. The network originally served as a competitor to AMC \u2013 which at the time was known as \"American Movie Classics\" and maintained a virtually identical format to TCM, as both networks largely focused on films released prior to 1970 and aired them in an uncut, uncolorized, and commercial-free format. AMC had broadened its film content to feature colorized and more recent films by 2002 and abandoned its commercial-free format, leaving TCM as the only movie-oriented cable channel to devote its programming entirely to classic films without commercial interruption.\n\nIn 1996, Turner Broadcasting System merged with Time Warner, which besides placing Turner Classic Movies and Warner Bros. Entertainment under the same corporate umbrella, also gave TCM access to Warner Bros.' library of films released after 1949 (which itself includes other acquired entities such as the Lorimar, Saul Zaentz and National General Pictures libraries); incidentally, TCM had already been running select Warner Bros. film titles through a licensing agreement with the studio that was signed prior to the launch of the channel. In March 1999, MGM paid Warner Bros. and gave up the home video rights to the MGM/UA films owned by Turner to Warner Home Video.\n\nIn 2000, TCM started the annual Young Composers Film Competition, inviting aspiring composers to participate in a judged competition that offers the winner of each year's competition the opportunity to score a restored, feature-length silent film as a grand prize, mentored by a well-known composer, with the new work subsequently premiering on the network. As of 2006, films that have been rescored include the 1921 Rudolph Valentino film Camille, two Lon Chaney films: 1921's The Ace of Hearts and 1928's Laugh, Clown, Laugh, and Greta Garbo's 1926 film The Temptress.\n\nIn 2008, TCM won a Peabody Award for excellence in broadcasting. In April 2010, Turner Classic Movies held the first TCM Classic Film Festival, an event \u2013 now held annually \u2013 at the Grauman's Chinese Theater and the Grauman's Egyptian Theater in Hollywood. Hosted by Robert Osborne, the four-day long annual festival celebrates Hollywood and its movies, and features celebrity appearances, special events, and screenings of around 50 classic movies including several newly restored by the Film Foundation, an organization devoted to preserving Hollywood's classic film legacy.\n\nTurner Classic Movies essentially operates as a commercial-free service, with the only advertisements on the network being shown between features \u2013 which advertise TCM products, network promotions for upcoming special programs and the original trailers for films that are scheduled to be broadcast on TCM (particularly those that will air during the primetime hours), and featurettes about classic film actors and actresses. In addition to this, extended breaks between features are filled with theatrically released movie trailers and classic short subjects \u2013 from series such as The Passing Parade, Crime Does Not Pay, Pete Smith Specialties, and Robert Benchley \u2013 under the banner name TCM Extras (formerly One Reel Wonders). In 2007, some of the short films featured on TCM were made available for streaming on TCM's website. Partly to allow these interstitials, Turner Classic Movies schedules its feature films either at the top of the hour or at :15, :30 or :45 minutes past the hour, instead of in timeslots of varying five-minute increments.\n\nTCM's film content has remained mostly uncut and uncolorized (with films natively filmed or post-produced in the format being those only ones presented in color), depending upon the original content of movies, particularly movies released after the 1968 implementation of the Motion Picture Association of America's ratings system and the concurrent disestablishment of the Motion Picture Production Code. Because of this, TCM is formatted similarly to a premium channel with certain films \u2013 particularly those made from the 1960s onward \u2013 sometimes featuring nudity, sexual content, violence and/or strong profanity; the network also features rating bumpers prior to the start of a program (most programs on TCM, especially films, are rated for content using the TV Parental Guidelines, in lieu of the MPAA's rating system).\n<Assistant>I understand. I'll keep this in mind.", "[Dialogue between User and Assistant on 2024-01-10 00:00]\n<User>Let me provide you with some new details:\nThe network's programming season runs from February until the following March of each year when a retrospective of Oscar-winning and Oscar-nominated movies is shown, called 31 Days of Oscar. As a result of its devoted format to classic feature films, viewers that are interested in tracing the career development of actresses such as Barbara Stanwyck or Greta Garbo or actors like Cary Grant or Humphrey Bogart have the unique opportunity to see most of the films that were made during their careers, from beginning to end. Turner Classic Movies presents many of its features in their original aspect ratio (widescreen or full screen) whenever possible \u2013 widescreen films broadcast on TCM are letterboxed on the network's standard definition feed. TCM also regularly presents widescreen presentations of films not available in the format on any home video release.\n\nTCM's library of films spans several decades of cinema and includes thousands of film titles. Besides its deals to broadcast film releases from Metro-Goldwyn-Mayer and Warner Bros. Entertainment, Turner Classic Movies also maintains movie licensing rights agreements with Universal Studios, Paramount Pictures, 20th Century Fox, Walt Disney Studios (primarily film content from Walt Disney Pictures, as well as most of the Selznick International Pictures library), Sony Pictures Entertainment (primarily film content from Columbia Pictures), StudioCanal, and Janus Films.\n\nMost Paramount sound releases made prior to 1950 are owned by EMKA, Ltd./NBCUniversal Television Distribution, while Paramount (currently owned by Viacom) holds on to most of its post-1949 releases, which are distributed for television by Trifecta Entertainment & Media. Columbia's film output is owned by Sony (through Sony Pictures Television); distribution of 20th Century Fox's film library is handled for television by its 21st Century Fox subsidiary 20th Television, and the Walt Disney Studios (owned by The Walt Disney Company) has its library film output handled for television by Disney-ABC Domestic Television. Classic films released by 20th Century Fox, Paramount Pictures, Universal Studios, and Columbia Pictures are licensed individually for broadcast on Turner Classic Movies.\n\nMost feature movies shown during the prime time and early overnight hours (8:00 p.m. to 2:30 a.m. Eastern Time) are presented by film historian Robert Osborne (who has been with the network since its 1994 launch, except for a five-month medical leave from July to December 2011, when guest hosts presented each night's films) on Sunday through Wednesday evenings \u2013 with Osborne only presenting primetime films on weekends \u2013 and Ben Mankiewicz presenting only late evening films on Thursdays, and the \"Silent Sunday Nights\" and \"TCM Imports\" blocks on Sundays.\n\nTCM regularly airs a \"Star of the Month\" throughout the year on Wednesdays starting at 8:00 p.m. Eastern Time, in which most, if not all, feature films from a classic film star are shown during that night's schedule. Hosted by Robert Osbourne, the network also marks the occurrence of a film actor's birthday (either antemortem or posthumously) or recent death with day- or evening-long festivals showcasting several of that artist's best, earliest or least-known pictures; by effect, marathons scheduled in honor of an actor's passing (which are scheduled within a month after their death) pre-empt films originally scheduled to air on that date. TCM also features a monthly program block called the \"TCM Guest Programmer\", in which Osborne is joined by celebrity guests responsible for choosing that evening's films (examples of such programmers during 2012 include Jules Feiffer, Anthony Bourdain, Debra Winger, Ellen Barkin, Spike Lee, Regis Philbin and Jim Lehrer); an offshoot of this block featuring Turner Classic Movies employees aired during February 2011.\n\nTurner Classic Movies also airs regularly scheduled weekly film blocks, which are periodically preempted for special themed month-long or seasonal scheduling events, such as the \"31 Days of Oscar\" film series in the month preceding the Academy Awards and the month-long \"Summer Under the Stars\" in August; all featured programming has their own distinctive feature presentation bumper for the particular scheduled presentation. The Essentials, currently hosted by Osborne and Sally Field as of 2015[update], is a weekly film showcase airing on Saturday evenings (with a replay on the following Sunday at 6:00 p.m. Eastern Time), which spotlights a different movie and contains a special introduction and post-movie discussion.\n\nThe channel also broadcasts two movie blocks during the late evening hours each Sunday: \"Silent Sunday Nights\", which features silent films from the United States and abroad, usually in the latest restored version and often with new musical scores; and \"TCM Imports\" (which previously ran on Saturdays until the early 2000s[specify]), a weekly presentation of films originally released in foreign countries. TCM Underground \u2013 which debuted in October 2006 \u2013 is a Friday late night block which focuses on cult films, the block was originally hosted by rocker/filmmaker Rob Zombie until December 2006 (though as of 2014[update], it is the only regular film presentation block on the channel that does not have a host).\n\nEach August, Turner Classic Movies suspends its regular schedule for a special month of film marathons called \"Summer Under the Stars\", which features entire daily schedules devoted to the work of a particular actor, with movies and specials that pertain to the star of the day. In the summer of 2007, the channel debuted \"Funday Night at the Movies\", a block hosted by actor Tom Kenny (best known as the voice of SpongeBob SquarePants). This summer block featured classic feature films (such as The Wizard of Oz, Sounder, Bringing Up Baby, Singin' in the Rain, Mr. Smith Goes to Washington, The Adventures of Robin Hood and 20,000 Leagues Under the Sea) aimed at introducing these movies to new generations of children and their families.\n\n\"Funday Night at the Movies\" was replaced in 2008 by \"Essentials Jr.\", a youth-oriented version of its weekly series The Essentials (originally hosted by actors Abigail Breslin and Chris O'Donnell, then by John Lithgow from 2009 to 2011, and then by Bill Hader starting with the 2011 season), which included such family-themed films as National Velvet, Captains Courageous and Yours, Mine and Ours, as well as more eclectic selections as Sherlock, Jr., The Music Box, Harvey, Mutiny on the Bounty and The Man Who Knew Too Much.\n\nIn addition to films, Turner Classic Movies also airs original content, mostly documentaries about classic movie personalities, the world of filmmaking and particularly notable films. An occasional month-long series, Race and Hollywood, showcases films by and about people of non-white races, featuring discussions of how these pictures influenced white people's image of said races, as well as how people of those races viewed themselves. Previous installments have included \"Asian Images on Film\" in 2008, \"Native American Images on Film\" in 2010, \"Black Images on Film\" in 2006 \"Latino Images on Film\" in 2009 and \"Arab Images on Film\" in 2011. The network aired the film series Screened Out (which explored the history and depiction of homosexuality in film) in 2007 and Religion on Film (focusing on the role of religion in cinematic works) in 2005. In 2011, TCM debuted a new series entitled AFI's Master Class: The Art of Collaboration.\n\nIn December 1994, TCM debuted \"TCM Remembers\", a tribute to recently deceased notable film personalities (including actors, producers, composers, directors, writers and cinematographers) that occasionally airs during promotional breaks between films. The segments appear in two forms: individual tributes and a longer end-of-year compilation. Following the recent death of an especially famous classic film personality (usually an actor, producer, filmmaker or director), the segment will feature a montage of select shots of the deceased's work. Every December, a longer, more inclusive \"TCM Remembers\" interstitial is produced that honors all of the noted film personalities who died during the past year, interspersed with scenes from settings such as an abandoned drive-in (2012) or a theatre which is closing down and is being dismantled (2013). Since 2001, the soundtracks for these clipreels have been introspective melodies by indie artists such as Badly Drawn Boy (2007) or Steve Earle (2009).\n\nThe TCM Vault Collection consists of several different DVD collections of rare classic films that have been licensed, remastered and released by Turner Classic Movies (through corporate sister Warner Home Video). These boxed set releases are of films by notable actors, directors or studios that were previously unreleased on DVD or VHS. The sets often include bonus discs including documentaries and shorts from the TCM library. The initial batch of DVDs are printed in limited quantities and subsequent batches are made-on-demand (MOD).\n<Assistant>I've processed this information and will remember it."]
[{"question": "In what year did Spike Lee appear as a TCM Guest Programmer?", "answer": "2012"}, {"question": "Who starred in The Temptress?", "answer": "Greta Garbo"}, {"question": "In what year did TCM begin the Young Composers Film Competition?", "answer": "2000"}, {"question": "In what month of the year does a longer version of TCM Remembers appear?", "answer": "December"}, {"question": "When did RCA release the 45?", "answer": "March 1949"}, {"question": "What invention did Thomas Hutchinson introduce?", "answer": "spider"}, {"question": "In which country was the treble roll off greater?", "answer": "US"}, {"question": "In what era could you find good quality recordings and playbacks at home?", "answer": "1940s"}, {"question": "What company out of Japan offered laser turntables that read vinyl discs optically?", "answer": "ELPJ"}, {"question": "What was used in final recordings of vinyl records?", "answer": "harder lacquer"}, {"question": "In what year did the Motion Picture Production Code cease?", "answer": "1968"}, {"question": "In what year did Screened Out appear?", "answer": "2007"}, {"question": "What is the expected finish of a vinyl record?", "answer": "mirror-like"}, {"question": "When were recording standards officially released?", "answer": "1949"}, {"question": "Which have stronger structures the father or son mold?", "answer": "sons"}, {"question": "When does the Summer Under the Stars event take place?", "answer": "August"}, {"question": "What movie block shows foreign films?", "answer": "TCM Imports"}, {"question": "What is the Spanish version of Turner Classic Movies?", "answer": "TCM Espa\u00f1a"}, {"question": "How is sound encoded on a commercial disc?", "answer": "by fine variations"}, {"question": "What is the primary use of IRENE?", "answer": "retrieve the information"}, {"question": "Who hosts the Star of the Month films?", "answer": "Robert Osbourne"}, {"question": "Who presents films on TCM on Wednesday nights?", "answer": "Robert Osborne"}, {"question": "Which format is cheaper, LP or EP?", "answer": "LPs"}, {"question": "How far back did records show the art of sound recordings?", "answer": "1925"}, {"question": "Where were sound recordings originally made to?", "answer": "master disc"}, {"question": "Who would engrave the master disc of a vinyl record?", "answer": "record cutter"}, {"question": "When would you have first found the moving coil microphone?", "answer": "around 1930"}, {"question": "What were used to make vinyl pressings?", "answer": "master cuts"}, {"question": "Which format held recordings ranging from 10 to 15 minutes?", "answer": "7-inch EP"}, {"question": "What is the center where the data joins to complete a circle?", "answer": "lock groove"}, {"question": "What was used to dampen resonances in recordings?", "answer": "Magnetic pickups"}, {"question": "Why did Robert Osborne stop presenting films on TCM for several months?", "answer": "medical leave"}, {"question": "What were TCM Extras previously known as?", "answer": "One Reel Wonders"}, {"question": "What do the TCM Vault Collection bonus discs feature in addition to documentaries?", "answer": "shorts"}, {"question": "In which year did Mercury begin 3 channel stereo recording?", "answer": "1955"}, {"question": "What is the cause of lock grooves on vinyl records?", "answer": "Dust and scratches"}, {"question": "What do most automatic turn tables do when they meet a lock groove?", "answer": "lift the arm"}, {"question": "Who created the CD-4 format?", "answer": "RCA"}, {"question": "What kind of recordings worked best for pop music?", "answer": "45 rpm"}, {"question": "Who developed the New Orthophonic curve?", "answer": "RCA Victor"}, {"question": "What was used in first recordings of vinyl records?", "answer": "soft wax"}, {"question": "For what reason is a Peabody Award granted?", "answer": "excellence in broadcasting"}, {"question": "What was the benefit of 45/45 stereo sound?", "answer": "more natural listening experience"}, {"question": "When TCM premiered, what was AMC called?", "answer": "American Movie Classics"}, {"question": "What was used for longer recordings?", "answer": "LP record"}, {"question": "How compatible were DBX encoded recordings with prior technologies?", "answer": "completely incompatible with"}, {"question": "Where can you find only 200-210mm of vinyl?", "answer": "ending of the groove"}, {"question": "What bass settings were needed to eliminate hum?", "answer": "below 100 Hz"}, {"question": "What were the plastic inserts which would adapt 45s to the smaller spindle of an LP player called?", "answer": "spider"}, {"question": "What is a common damage to vinyl records?", "answer": "easily scratched."}, {"question": "Who developed the 3-to-2 mix to create lifelike recordings?", "answer": "Mercury"}, {"question": "What retrospective of the Oscars is shown yearly on TCM?", "answer": "31 Days of Oscar"}, {"question": "When did MGM give Warner Home Video the rights to MGM/UA's films on home video?", "answer": "March 1999"}, {"question": "Who provided the soundtrack for the longer TCM Remembers episode in 2009?", "answer": "Steve Earle"}, {"question": "After the initial batch of TCM Vault Collection DVDs are printed, how are they made afterwards?", "answer": "on-demand"}, {"question": "Does IRENE require the  ability to touch the media?", "answer": "without touching the medium"}, {"question": "How would the commercial success of quadraphonic records be defined?", "answer": "commercially unsuccessful"}, {"question": "What was the quality of sound recordings made with horns at the end of the acoustic era?", "answer": "many fine examples"}, {"question": "What magazines provided reviews for audio equipment?", "answer": "High Fidelity and Audio"}, {"question": "What was a benefit of the use of magnetic pickup cartridge?", "answer": "high quality cuts"}, {"question": "In what year did TCM receive a Peabody Award?", "answer": "2008"}, {"question": "Along with The Passing Parade, Crime Does Not Pay and Pete Smith Specialties, what short subjects feature on TCM?", "answer": "Robert Benchley"}, {"question": "How many films are present in the TCM library?", "answer": "thousands"}, {"question": "Is it difficult to transfer recording from historic interest to newer technologies?", "answer": "Anyone can do this"}, {"question": "Along with individual tributes, what form did TCM Remembers occur in?", "answer": "end-of-year compilation"}, {"question": "In what year did Badly Drawn Boy provide a soundtrack for TCM Remembers?", "answer": "2007"}, {"question": "In what year did Funday Night at the Movies first appear?", "answer": "2007"}, {"question": "What would offer the highest quality transfers of historic interest?", "answer": "professional archivists"}, {"question": "How many colors were 45s available in when first released?", "answer": "seven colors"}, {"question": "How often is the Young Composers Film Competition?", "answer": "annual"}, {"question": "What happens when frequency decreases in the bass?", "answer": "recording amplitude increased"}, {"question": "For which company did C. Robert Fine work for?", "answer": "Mercury Records"}, {"question": "In what month and year did TCM Remembers premiere?", "answer": "December 1994"}, {"question": "In which Era was this finding most significant?", "answer": "1925 era"}, {"question": "How much vinyl can be found at the start of an LP?", "answer": "510 mm"}, {"question": "What benefit did the use of the Wente style condenser microphone offer?", "answer": "brilliant midrange"}, {"question": "When frequency in the treble increases what happens to the recording amplitude?", "answer": "recording amplitude decreased"}, {"question": "What is a drawback of gramophone use?", "answer": "gradual degradation"}, {"question": "When did EMI create the first stereo discs?", "answer": "1933"}, {"question": "What could be avoided by using vertical groove cuts?", "answer": "inner groove distortion"}, {"question": "What did closer groove spacing result in?", "answer": "Lower recorded volume"}, {"question": "How similar was the sound of a orthodontic  record to a radio?", "answer": "sounded like"}, {"question": "What is the material preference of collectors?", "answer": "heavyweight vinyl"}, {"question": "Along with Lorimar and National General Pictures, what library was included in the Warner Bros. library?", "answer": "Saul Zaentz"}, {"question": "What is a feature many stereos contain to fight back against unwanted noises?", "answer": "subsonic filter"}, {"question": "How did the NBC Othacoustic curve relate to the NAB curve?", "answer": "remarkably similar"}, {"question": "In what year did Arab Images on Film first appear?", "answer": "2011"}, {"question": "Along with :45, :30 and :15 past the hour, at what time do TCM features begin?", "answer": "top of the hour"}, {"question": "What series replaced Funday Night at the Movies?", "answer": "Essentials Jr."}, {"question": "Up until what month and year of release are films from Metro-Goldwyn-Mayer part of the Turner Entertainment library?", "answer": "May 1986"}, {"question": "By what year was AMC showing commercials?", "answer": "2002"}, {"question": "What was a more economical option to magnetic pickups?", "answer": "Crystal pickups"}, {"question": "How far back could these recording practices be traced?", "answer": "1925"}, {"question": "What was a benefit of vertical groove cuts?", "answer": "longer playback time"}, {"question": "What was a drawback of laser read discs?", "answer": "degrade the sound"}, {"question": "What medium has seen the biggest fall in sales as of late?", "answer": "compact discs"}, {"question": "As of 2015, who hosted The Essentials along with Robert Osborne?", "answer": "Sally Field"}, {"question": "Who was the first host of TCM Underground?", "answer": "Rob Zombie"}, {"question": "How many subscribers had access to TCM upon it launch?", "answer": "one million"}, {"question": "When does TCM's programming season begin?", "answer": "February"}]