Towering presence . . . the revamped Royal Shakespeare theatre. Photograph: David Sillitoe for the Guardian  When the renovation of the Royal Shakespeare theatre at Stratford-upon-Avon was first announced, someone asked why the number of seats was to fall by 400. Surely this was against the notion of "accessibility" or "art for all"? Michael Boyd, artistic director of the RSC, boomed: "This isn't football – you're meant to be able to hear what the actors are saying."  The sheer scale of the old theatre had long been a problem. So great was the distance between the proscenium stage and the back row that even the stormiest Lear was all but inaudible to those seats. "It might be apocryphal," says Rab Bennetts of Bennetts Associates, the architects behind the newly unveiled £112m revamp, "but one actor claimed that reciting from the old stage was like addressing Calais from the white cliffs of Dover."  Although the adjoining Swan theatre has also been given a spruce-up, the most fundamental change to this much respected, if not always loved, theatre complex on the banks of the Avon has been to the main theatre: the 1,400-seat art deco auditorium, designed by Elisabeth Scott in 1927, has been demolished, and replaced with what is intended to be a stage in the style of Shakespeare's day, but brought up to date. So brick and concrete co-exist, as well as timbers that are both ancient and freshly sawn. There's also a thrust stage jutting into the audience. Actors on the new stage are now about 15 metres, rather than 27, from the back row, so it's goodbye to that declamatory performing style.  "Although it was listed," says Bennetts, "the old theatre was strangely remote and uninviting. It turned its back on the town, showing a tough brick face to the streets. Locals called Scott's building the Jam Factory, and, despite its distinguished art deco lobbies and rooms, it did have the look of an industrial building of the 1930s."  The complex has a complicated history. Called the Shakespeare Memorial theatre when it opened in 1879, it was a flamboyant piece of Victorian gothic until fire struck in 1926. Scott's art deco theatre was built into those parts that survived. For more than two decades now, the complex has also been home to the much-feted 450-seat Swan theatre, created within fire-damaged walls. Used for productions of Shakespeare's more intimate plays, and those of his contemporaries, the Swan has been the model for the reconstructed Royal Shakespeare theatre.  The RSC had planned to demolish the whole caboodle and build afresh. But in 2003, times, finances, aspirations and artistic and architectural direction changed as Boyd took over. A more "as you find it" experience was chosen: a pair of Shakespearean theatres linked together with a weave of empathetic new architecture, creating a convincing and effective whole. More than this, the old theatres would be made to address the town, and open themselves up to the public whether they were coming to sit through King Lear or not.  The Scott building has been stripped of all later accretions and given a new public entrance that stretches into a broad, bricked arcade linking it with the older building. A new restaurant now tops the Scott section, which boasts a 36-metre lift and viewing tower, faced in handmade brick. This urban eyecatcher acts, Bennetts says, as "an anchor, mooring a fleet of theatrical buildings". It also serves as a giant mast or flagpole, proudly drawing attention to the RSC's home. Views from the top, through glass louvres, are of four counties and every local site associated with Shakespeare himself.  The new entrance, by the base of the tower, leads visitors and theatregoers into Bennetts's arcade and into the original art deco entrance lobby, now an airy bar. These spaces flow seamlessly into a second lobby. Here you walk on teak planks taken from the old stage, meaning you tread the very boards that Olivier trod years ago.  The Royal Shakespeare theatre itself – the heart of the project – feels impressive and likable. Three tiers of upholstered red seats surround the thrust stage. The feeling is both grand and intimate, exciting and stark, what with those riveted steel joists and unpolished timber. Sound and sensation are all. We will, though, have to wait until next spring, when plays are first performed in here, to judge it properly.  Backstage is enormous, with smart dressing rooms overlooking the Avon, their balconies softening that hard brick exterior. In fact, the complex, especially its tower, has the picturesque quality of some half-imagined Italian town, where the action of some Shakespeare play might take place: two theatres of Verona, if you like. The grouping of the buildings works well; that arcade has power and charm. The complex feels like a town in itself, one that now reaches out to its surroundings.  Bennetts and his team have done well to bring so many styles – gothic, art deco, Modern – into a cohesive whole, especially one with riveted steel, rusted steel and steel as smooth as lacquered wood. Great things deserve to happen here, and great Shakespearean speeches given. And now you'll even be able to hear them from the cheap seats.
. . . that ends well. At last, Stratford-upon-Avon finally has a theatre worthy of Shakespeare's name, writes Jonathan Glancey