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Direct-to-Disc at AES

by Robert Auld

At the 2001 Audio Engineering Convention in New York City, the 1970's art of audiophile direct-to-disc recording was revived for convention attendees. Here is a report of what happened, along with photographs and an MP3 file of one of the recordings made at the session.

The author at the tube mixing consoleThese days, the term "direct-to-disc" means recording to a computer hard drive. But in the 1970's, it referred to the audiophile technique of recording directly to a vinyl-disc cutting lathe, without the intervention of a tape recorder. It was a notoriously difficult way to record; the musicians and all concerned had to record a complete Lp side without any serious musical or technical mistakes. Otherwise, it was put another lacquer on the lathe and do it over. But the gain in sound quality was considered worth the trouble. (As typical commercial Lp releases were cut from fourth-generation analog tape copies, the improvement in sound offered by eliminating all those layers of tape and electronics was not illusory.)

At the fall 2001 AES convention in New York City, the AES Historical Committee presented a second installment of the "When Vinyl Ruled" exhibit that had been so successful at the 2000 Los Angeles convention. The emphasis was the same: visitors would encounter a working recording studio consisting mostly of recording equipment from the 1950's and 1960's. To this end, the exhibit working committee in New York obtained 2-track and 3-track vintage analog tape recorders by Scully and Ampex, a custom built all-tube mixing console, three Altec A-7 "Voice of the Theatre" loudspeakers powered by McIntosh tube amps, an AKG BX-20 reverb (vintage late 1960's), and for Lp playback, a classic Thorens turntable (also vintage 1960's).

The author at the tube mixing console. The Scully 280
backup recorder is partly visible in the foreground.
Photo by Howard Sanner)

The piece-de-resistance of all this vintage equipment was a fully restored and operating Neumann VMS-70 disc cutting system set up in one corner of the exhibit room. Throughout the convention, veteran engineer Al Grundy demonstrated the art of vinyl disc mastering on this beauty.

Irv Joel, the co-head of the exhibit working committee, appointed me as the engineer for the direct-to-disc recording session. It was my job to select and place the microphones, do a live mix on the tube console, and generally do whatever was necessary to ensure that Al Grundy got a musical signal worth recording on the cutting lathe. Fortunately I had plenty of help with this task; Irv, his fellow co-head John Chester, Paul McManus (a prime mover of the previous Los Angeles exhibit), and many other members of the committee assisted in ways too numerous to recount here.

The band during a take

The band during a take. (Photo by Howard Sanner)

We were fortunate in the musical group that was engaged for the recording session. Keyboard player Rob Aries brought us a jazz/fusion quartet, which also featured Bill Harris on tenor sax, Dave Anderson on fender bass and Terry Silverlight on drums. They were all superb musicians, which made my job much easier than it could have been. Due to the half acoustic - half electric nature of the group, and the fact that we were recording in an exhibit room with indifferent acoustics and potential background noise problems, I decided on a conservative multi-microphone setup with the electronic instruments recorded through direct boxes. For a comprehensive explanation of the recording setup with floor plan, block diagram, etc., follow this link.

Thanks to the extensive planning and preparation beforehand, the recording session went smoothly. Historical Committee member David Baker gave a short spoken introduction to the audience. I then explained the recording setup and Al Grundy spoke about the particular technical issues relevant to recording directly to the disc cutting lathe from a live signal. He then cut the lead-in to the first master lacquer, I cued the band to start playing, and off we went.

In order to minimize groove spacing problems, the stress on the musicians, etc., we had decided to record only one tune per lacquer disc. This was, after all, only a demonstration of direct-to-disc recording technique; the creation of a commercial Lp issue was not our intent. After the first tune had been recorded, Al cued up the master lacquer and played it back through the Altec speakers. I had never heard playback from a freshly cut master lacquer before. The fidelity was remarkable; wide dynamic range, clean transients, all against a dead quiet background. The big theater speakers were able to match the level of the live band in the room without strain, which made the comparison all the more impressive.

(The MP3 file available for download from this page will give you some idea of what we heard. It is not a dub of the master lacquer, but is derived from the analog backup tape, recorded from the same mix as was sent to the cutting lathe.)

Al Grundy at the Neumann lathe

Al Grundy at the Neumann lathe.(Photo by Howard Sanner)

Al Grundy deserves a lot of credit for the success of the AES direct-to-disc session. There are a lot of things that can go wrong with a disc cutting lathe, and the direct-to-disc recordings of the 1970's experienced their share of technical problems. One of the more dramatic examples occurred during a recording by the Louie Bellson big band, when the thread of vinyl being cut from the disc managed to wrap itself around the cutting stylus and ignited, starting a fire in the cutting room! We experienced no such excitement at the Javits center. We recorded five tunes and Al cut five flawless discs. This is a good example of making the difficult look easy.

-Robert Auld, 1/28/02


Contact Rob Aries

Contact Bill Harris

Contact Terry Silverlight

Contact Robert Auld

Howard Sanner is a member of the AES Historical Committee. He maintains the Committee's web site at

Session MP3 file

Three For Peace by Dave Anderson, was the first tune recorded at the session. This MP3 file was derived from the backup tape recorded on the Scully 280 open reel recorder. Encoding is at 160 kbits/sec, with a file size of about 5.2 mb. Download time will depend, of course, on your speed of connection.

Note: Windows users have a couple of options for downloading. If you left-click on the link, what happens is to some degree dependent on the settings of your browser, but the file should load to a temporary file on your hard disk, after which it will begin playing in your default player. If you right-click on the link, you will be offered a pop-up menu with "Save link as..." being one of the choices. You may then select that choice and save the file on your hard disc.

It goes without saying (but I'll say it anyway) that this MP3 file is only for the private use of visitors to this site. Commercial distribution is prohibited.

Download Three For Peace (excerpt)

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