Remembering Roy Wallace, recording engineer, and his Decca Tree

Roy Wallace was the creator of stereo balance at the Decca Recording Company, and its first engineer, beginning a tradition and standard of excellence that has not been bettered during the past half century. He designed and built the equipment that was to prove so successful for the company through successive decades.

Wallace was attracted to music from the age of eight, although he never received any formal training. His first
job, in 1942, when he was 15, was at Radio and Television Engineering which produced radar equipment and early electrocardiogram machines. It was here that he met Lawrence Francis Savage, owner of RTE.

Savage had been involved in BBC experiments with stereo sound during 1938-39. In 1947, he explained to Wallace the principle of binaural sound (as he called it) and the pre-war experiments he had made. The early, primitive equipment was overhauled so that twin-track discs could be played using a parallel-tracking pick-up arm with two crystal stylus heads positioned on a gantry. It had been necessary to use 16-inch discs rotating at 331/3rpm in order to get any reasonable playing time.

Wallace then constructed an experimental artificial head
containing three crystal microphones – one central and two angled 70 degrees left and right. He next designed and built a three-channel sound mixer (which he called ST1) to reduce the three inputs into two outputs. Wallace had built a second version of the Francis channelling equipment by November 1952 so that Savage and he were able to demonstrate all their gear to Decca.

The chairman of the Decca Record Company, Edward Lewis, was
impressed by what he heard and gave the go-ahead to continue. Lewis had realised that stereo sound was the
future and Wallace was asked to join Decca and take over the stereo business. Wallace scrapped all the earlier workings and began again. He devised a frequency transposition
system, with one channel 50H to 9KHz, another of 12KHz to
21KHz with a carrier/pilot frequency right in the middle from 9-10KHz.

By November 1953 the new system was working so that it was possible to play Beethoven on one channel and the pianist Winifred Attwell on the other, through just one pair of
lines into the decoder. An experimental session took place
on 23 December 1953 when the conductor Mantovani and his
orchestra were booked. Three Telefunken M49 microphones
(left, right and centre) were bolted to a couple of Dexion uprights. The recordings were cut direct to disc as there was no twin-track stereo tape recorder. The wax acetates were sent to Decca’s New Malden factory for processing and eventually Wallace was able to demonstrate what had been achieved. The results were thought remarkable and the stereo
image fine.

With no stereo mixing desk available Wallace stripped down a standard Decca six-channel mono machine, redesigning and making a stereo mixer with two banks of three inputs. He then built two new power amplifiers in weeks. An Ampex 350
series 1 twin-track tape machine arrived late in April 1954 and a further experimental session was undertaken to make sure everything worked.

The equipment was taken to Geneva and on 13 May the Swiss conductor Ernest Ansermet was set to record
Rimsky-Korsakov’s Antar. The first movement was recorded complete and Ansermet remarked how thrilled he was with the sound, stating that it was as if he was standing on the
conductor’s rostrum.

Two months later, Wallace flew to Basle with his assistant, James Brown, who went on to become another prominent Decca sound engineer, collected the ST2 mixer and other equipment, and set up the stereo gear in Rome. Three operas, Manon
Lescaut, Otello and La traviata, all with the soprano Renata Tebaldi, were recorded experimentally. After sessions in Paris, Geneva and Belgrade, Wallace returned to London to work on two new mixers.

In July and August 1955 Decca recorded the two cycles of Wagner’s Ring plus Der fliegende Holländer under Josef Keilberth at the 1955 Bayreuth Festival. By using six
microphones, three for the orchestra and three for the singers, hung from the lighting bridge above the stage, the sounds were fed into the six-channel mixer ST2. However, no
contracts were issued with the artists and the tapes lay in Decca’s library until Testament released them on CD at the beginning of last year. Critical response to these recordings made by Roy Wallace was unanimous in its praise of the stereo sound.

Wallace had always wanted to return to the engineering side of the business. With his colleague Bob Goodman he built a new mixer called Maspere (an anagram of amperes, standing for “mono and stereophonic electronic recording equipment”).
It was a two-track (stereo) mixing desk. Decca continued to want larger multi-channel mixers and the next became known as STORM 64. Five different sets were produced, the project occupying the years 1965-77. These remained in use from 1966
until 1988, some later models adapted to replace the four-track facility for eight-track usage.

Wallace received his 25 years’ service award in 1978, retiring from Decca as PolyGram took it over in 1980.

He was born in London 7 July 1927, and died in London 18 August 2007.

Malcolm Walker’s obituary

The Independent
13 October 2007

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