Andrew Rose: Restoring Old Recordings

Andrew Rose has built a successful business by restoring and releasing great lost recordings of the 20th Century. He explains how he brings back the original magic...

From the top floor of a house in a sleepy village in south‑west France, battered 78s and dusty, mangled tapes are reborn from an Aladdin's cave of esoteric sound equipment. Part curator, part avid classical music fan, Andrew Rose is a leading expert in audio restoration; he is also one of few in the music industry who has made a success of online music retailing, selling thousands of downloads every year via his company Pristine Audio. He has even dabbled in forensic audio, helping to expose the recent Joyce Hatto music hoax and examining supposed 'new' material in Michael Jackson's posthumous DVD (see 'Getting To The Truth' box).

Now 42, Rose studied music at the City University in London, and joined the BBC in 1990 as a trainee studio manager. After leaving his post as senior studio manager at Radio 4, he moved to the Dordogne in early 2004 with his wife and young son, and converted the top level of their new home into a studio, office and storage area for his huge collection of vintage gear and recordings. Andrew explains: "I started Pristine Audio in 2002, purely as a sideline to my job, because of my interest in transfers. I began with moving LPs to CDs, and put out a few adverts, and work slowly built up. I then got more work than I could handle, so I left my job and started doing transfers commercially. We sold our house in Kent, I bought a huge stash of 78s, and we moved to France.

Some the large library of rare material that Rose has transferred to digital and restored.

"It seemed to me that legal downloads were the way to go, but at that time there were no sites in Europe where you could pay for and legally download music. MP3s back then were a byword for piracy, iTunes in the USA had only just started and I was looking to get my transfers online. I had approached many companies about getting their back catalogues transferred and remastered, but their reply was invariably 'We'd love to, but we haven't got any money.' But I began to build up a catalogue of material, and in late 2004, a company called Payloadz allowed the sale of downloadable MP3s. My first customer was in March 2005 from Norway, and in that year I sold around 200 albums, half of which were also CDs.”

Things have since snowballed, to the extent that in the past 12 months, Andrew has sold around 5000 albums as downloads and another 5000 as CDs. His material is gathered from all over the world; some is from private collectors, but current copyright legislation means that all music broadcast or recorded in 1960 or earlier has become public domain. Some of the recordings are incredibly rare: he shows me a 1945 copy of Vladimir Horowitz playing Brahms' Second Piano Concerto with the NBC Symphony Orchestra, conducted by Arturo Toscanini, recorded to an aluminium disc covered with a thin layer of fragile acetate. He says "As far as we know, this is the only copy in existence. This disc was only designed to be played six or seven times, I have played it just once. I don't know its value but it is the rarest thing. Collectors let me use the recordings and I give them a copy of the restoration.”

Another oddity is a huge 16‑inch floppy vinyl recording from the USA. "They were designed to be transported across South America. Because they weren't brittle, they were less likely to break.”

The Holy Grail for transfer engineers is unplayed vinyl, but Andrew says you have to be prepared for anything, and his huge collection of playback equipment is a potted history of recording media (see 'Kit List' box). "The only thing I can't play is wax cylinders,” Andrew says. "Early jazz and blues recordings from the 1920s make good training, because the recordings were so bad. Companies like Paramount scouted great artists, but the quality of the equipment and, most particularly, their pressing, was terrible.”

Minimal Intervention

Andrew guides me through the process of transferring a 1942 recording of Barber's Adagio For Strings, conducted by Toscanini at the Carnegie Hall. ("Many of my techniques could not be used a few years ago. With my overclocked, quad‑core PC I can use the latest and highest quality noise‑reduction routines in [Izotope] RX2 in real time, but only in mono. Soon I'll be able to do the same in stereo. This would be impossible without powerful computers.”) On a 78rpm disc, the HMV pressing from an RCA Victor original is first cleaned in a disc‑washing machine using Disc Doctor's Miracle Record Cleaner, then rinsed with medical‑grade water, then vacuumed. Played back on Rose's Rega Planar 78 deck, the mono disc is then recorded onto his PC using Adobe Audition 3, in stereo. It is then de‑clicked and de‑crackled using Adobe Audition's de‑clicker, Izotope's RX2 de‑clicker and Waves' X‑Crackle. The two channels are then combined to mono (starting with stereo gives a 3‑6dB boost in signal‑to‑noise ratio compared with working in mono all along). At this point it is put into Izotope RX2 for hum removal, de‑noising and the intensive manual job of individually removing remaining clicks and pops.

On another example, a 1943 magnetic tape recording sent in by a collector, of Beethoven's Fourth Symphony by the Berlin Philharmonic Orchestra, conducted by Wilhelm Furtwängler at the Alte Philharmonie, Berlin, Andrew shows me his technique of harmonic balancing. Using the Har‑Bal 'harmonic equaliser' software, a modern version of the same piece is analysed and an EQ 'fingerprint' is created. This is then compared and applied to the old recording, basically adding a dramatic EQ. Andrew says: "You're reverse‑engineering the flaws of the old microphone and recording chain. It flies in the face of all that we're taught about sound engineering, but it does bring life back to these recordings. However, this technique will bring up a whole lot of noise and rumble, which is when you have to start using your ears and intelligence.”

A rare find: this 1945 acetate might well be the only surviving recording of the performance.

In this example, the EQ adds a whopping 26.9dB of boost at 55Hz, so it goes back into RX2 again for adjustments. Andrew also re‑pitches the recording to A=440Hz using a solo instrument (usually woodwind) as a reference. A small amount of convolution reverb is also added to compensate for the very dry recording: "Early recordings were made in very dry environments, to allow the sound to punch through for a 78 disc. It wasn't until much later that real acoustic spaces were used. Convolution reverb allows you to give the piece a real sense of space, which is impossible with normal digital reverbs.”

When asked about the most challenging restoration projects he has faced, Andrew recalls a mangled 1954 quarter‑inch mono tape recording of an EJ Moeran violin concerto by the BBC Philharmonic Orchestra, conducted by Sir Adrian Boult. "It was a real labour of love. It took over four weeks to reconstruct 32 minutes of audio. The task was monumental. The tape was very badly damaged, it had drop‑outs, noise and crackles. It was at that point that spectral editing was available in Adobe; I was able to find other bits of harmonics of the same notes played by the same instruments, and paste them in using spectrographic editing.”

This labour of love was released to rave reviews on Divine Art Records in 2006. But Andrew adds: "The listener should not be able to hear how much effort has gone into it. The whole point of this is so that the piece can be enjoyed again and preserved. In the past, restorers have got a bad name for their 'intervention' in recordings. This was largely due to the personal taste of their interpretations, such as inappropriate EQ. What I'm trying to do is improve the fundamental non‑linearity of microphones from that era.”

All In The Mind

Vinyl records are prepared for transfer by washing in this specially designed machine.

The process of restoring a damaged recording is arduous, and, according to Andrew Rose, requires a very special mental attitude. "When I'm working on a recording, at each step of the way it's as if I'm listening to something else, purely by breaking down the various stages of the restoration and remastering process and only listening for specifics at any particular time. My initial concern is most likely to be equalisation, thus I'm listening purely to the tonal balance of a recording and ignoring clicks, hiss, coughs and so forth. These I'll come to later. Likewise the performance itself: because the recordings are already set in stone, and I've already made a decision on a particular performance by a particular artist, I needn't get too involved or sidetracked by the music itself and how it's being played. Although obviously from time to time they do grab my attention, it's best to try and mentally filter this out.

"The next phase is likely to be noise reduction, and again I'm listening only to specifics here. I'll probably ignore hiss on the first run and look for and listen out for hum, which usually requires notch filtering and is present on a great number of older recordings. Because I'm working almost entirely using spectrographic representations of music, the process is as much visual as auditory — I can zoom in and see lines of hum harmonics, for example. Later on, the same visuals allow me to see audience coughs and sneezes scrolling across the screen before I hear them, just as I can see the swishes on a 78rpm disc.

"Thus the process of going through a recording over and over again can be a little like going through different recordings — each time I'm concentrating on a different element and mentally filtering out the rest. In fact, the process of auditory filtering turns out to be more than a mental process: your brain can actually send instructions to the ear to physically suppress the reception of unwanted frequencies, so that ear and brain work in tandem. This also, I guess, explains why, if you're dealing with a huge amount of high‑frequency swish and concentrating on that, you can easily miss some big clicks and clunks at the low end — quite literally you didn't hear them, because your brain and ears had filtered them out for you. Hopefully, by the time I get to releasing a recording, I've been over it enough times to catch everything and deal with it. You always fear having to go back to a recording after it's online and ready to go, because a single click that's been missed, despite several restoration passes, now stands out like a sore thumb!

"Partly as a result of this, I usually have to wait a few weeks before I can engage with one of our releases on a purely musical level, and switch off the corner of my brain that is automatically tuning in for possible defects. Sometimes it's hard just to sit back and enjoy the music!”