Due for release on September 22 is 'Callas Remastered: The Complete Studio Recordings', a 69-disc Warner Classics box-set produced as the result of a major remastering project to transfer the original tapes to 24-bit/96kHz digital sound.

Containing 26 operas and 13 recital albums, and the subject of a major feature in Gramophone’s 2014 Awards issue, on sale now, the Callas project will also be available as 24-bit/96kHz downloads from the Bowers & Wilkins Society of Sound, exclusively from Monday (September 22) until October 5.

The new set encompasses all the studio recordings Callas made for both EMI/Columbia and the Italian label Cetra between 1949 and 1969, and while these recordings have previously been remastered at CD quality, remastering engineer Allan Ramsay explains that this is the first time the tapes have been remastered at 24-bit/96kHz ‘beyond CD’ quality: ‘What this means is we’ve now got more high-frequency content and better definition to the sound.

‘We’ve been so careful in this project not to tamper, just to remove technical faults…for example, to reduce the rumble from a passing tube train at the Kingsway Hall, even remove the noise of a motorbike outside La Scala, Vespas going past and you can hear this noise which is terrible, it’s louder than the singing in some cases. With the technology we have now, we can reduce this noise and give the sound of the voice without interference.’

The remastering was carried out at London’s Abbey Road Studios with Bowers & Wilkins 800 Series speakers used throughout the process. The Worthing-based speaker company has a relationship with the studios going back more than a quarter of a century. Abbey Road engineer Andy Walters says that, for a project like this, ‘It’s obviously important that the monitoring speakers and room acoustics of a remastering room are superb: Bowers & Wilkins speakers don’t flatter or compliment the sound, but give a complete, true response.

‘This means we can hear exactly what problems might exist on an original master recording and then be afforded the opportunity to put them right, using our state-of-the-art technology.’

‘Callas Remastered: The Complete Studio Recordings’ contains at least one complete recording (in certain cases two recordings) of all Callas’s most famous stage roles, with the exception of Anna Bolena, though the lengthy final scene of that opera features on the recital ‘Mad Scenes’. The collection also contains complete recordings of operas she sang on stage more rarely – or even never at all – such as Manon Lescaut and Carmen.