The First World War witnessed the consequences of the new and potent means of warfare at sea – the submarine. The German U-boat, as it was termed, became a grave and serious threat that inflicted considerable losses on Allied shipping. This led to significant changes in naval tactics and strenuous research efforts in the development of hydrophones and increasing the capability of underwater sound detection during and after the war.

The German U-boat threat returned with a vengeance in the Second World War and became an intractable problem with the grievous loss of life, materials and ships in the convoys. It was the combination of two separate events that not only enabled the Allies to eventually overcome and defeat the U-boats, but also contributed to the development of recorded high fidelity sound and the commercial post war success of the Decca Record Company.

The first occurred in May 1941, when Professor Blackett, head of the Admiralty's Anti-Submarine Warfare Committee presented a research proposal to develop an air-launched expendable sonobuoy for use by Coastal Command to locate and destroy submarines. He envisaged a small self-contained unit combining a hydrophone, radio transmitter, battery pack and small parachute fitted into an expendable buoy that would function for several hours before sinking. Blackett was concerned about the limited availability of resources and suggested that the Americans may be able to assist.1

The proposal was passed to Dr Pye at the Ministry of Aircraft Production who recognised the potential and also agreed with Blackett’s concern about the limitation on resources to undertake the research, test and manufacture of the sonobuoy. He wrote to Dr Darwin, Director of the Central Scientific Office in Washington DC, to advise him of the idea and enquire if American help would be available. It transpired that the Americans were already working on a similar project with sonobuoys deployed from ships to act as ‘gatekeepers’ for convoys.2

The trials had limited success and the project was eventually stopped because of other more pressing priorities. However, the airborne option was taken up and the first successful test took place in March 1942.3

The operational sonobuoy was cylinder shaped, approximately 3 feet in length and 5 inches in diameter. The top housed the parachute and VHF radio transmitter, with the hydrophone deployed from the bottom on a wire approximately 20 foot long. The casing was a thick paper tube covered in resin. The transmitting range was approximately 5 miles. Later models had metal casing, some with extra battery packs, and were designed to be recoverable. The first sonobuoy model, AN/CRT-1 and the accompanying radio receivers went into full-scale production and entered active service in 1942/43.

This joint effort between Britain and the United States provided a significant and effective step forward in antisubmarine warfare. Sonobuoys were dropped, usually five at a time with each tuned to a different radio frequency, in a pattern to enable aircrews to listen and locate a submarine more accurately before attacking.4

The Columbia University Division of War Research, based at the US Navy Underwater Sound Laboratory produced a series of training gramophone records with various submarine sounds recorded from sonobuoys. These sets became a part of Coastal Command’s training syllabus. 5

The second event was the capture of U-570, a type VIIC submarine, on 27 August 1941, south of Iceland in the North Atlantic. While on her first operational patrol a Coastal Command Hudson from 269 Squadron operating from Kaldadarnes in Iceland surprised the U-Boat on the surface in bad weather and dropped depth charges forcing the crew out onto the casing to surrender.

The vessel sustained damage during her capture and was towed to Iceland for repairs. She was subsequently sailed to Barrow-in-Furness by a British crew with a naval escort. The Admiralty took the golden opportunity to forensically examine the newly completed vessel (April 1941) by testing and measuring every aspect of its construction, equipment and performance.6

U570 in Barrow-in-Furness Royal Navy official photographer - photograph FL 951 from the Imperial War Museum.

After additional repairs she was renamed HMS Graph and underwent further extensive analysis of her seagoing performance and equipment. This included sound trials at sea and at the Admiralty Research Laboratory's acoustic range in Loch Goil, a small sea loch on the Cowal peninsula in Argyll and Bute, Scotland. During extensive comparative tests, that included another submarine HMS Sturgeon, it was discovered that the sound profile of the German vessel had a distinctively higher frequency range.7

Although higher frequencies could be broadcast and measured they could not be reproduced. The bandwidth of sound on gramophone records was typically 50-4000Hz, while the nominal range of human hearing is 20-20,000Hz. The means of reproduction was also rudimentary, hence 78rpm shellac records sound compressed, particularly the higher frequencies.

One of the key difficulties was that cutting heads tended to modulate at around 4000Hz which prevented a wider bandwidth being transferred to disc.8 Arthur Haddy, Decca’s chief recording engineer, was based at the Company’s Broadhurst Gardens studios in West Hampstead and had been working for sometime on the means of increasing recorded bandwidth. Using the nearby laboratory of Haynes Radio,9 he had experimented with a moving-coil rather than moving-iron cutting head and by 1939 had successfully increased the upper range to around 7500Hz.10

By 1939, the Decca Company had been established for ten years and had just emerged from a difficult financial period and was now on a firmer footing. The company was not on the initial list of official government contractors but had come to the attention of the Admiralty through their proposal for an accurate navigational system, subsequently code-named QM and successfully deployed as part of Operation Neptune on D-Day.11

Coastal Command needed recordings up to 12,000Hz for training crews to accurately interpret and identify what they were hearing from sonobuoy transmissions and crucially the difference between British and German vessels. Their request presented Decca with a significant challenge and as Haddy explained: "We went all out with high fidelity in a way that would have taken years in peacetime." 12

Haddy was also aware that part of the issue was ‘friendly fire’. Coastal Command crews worked in challenging and noisy conditions that presented significant difficulties in listening to sounds transmitted from sonobuoys and accurately identifying the source.

With a small team of assistants Haddy set about tackling the challenge. He eventually developed a cutting head that increased the frequency range, so enabling the full frequency range of sound from German U-Boats to be recorded.13

At Loch Goil further tests and recordings took place involving HMS Graph and HMS Satyr.14 Haddy noted that: "A German submarine sounded quite different from an English submarine. There was no mistaking it once you knew what to listen for. But the tell tale difference was a very high frequency sound. [..] We had to build a disc cutter that would handle the full range of human hearing. We built one that would go up to around 16kHz. Then we recorded the propeller noise of a captured German sub. Also the noise of a British sub. On headphones you could clearly hear the difference." 15

Records were subsequently produced and distributed to Coastal Command for training purposes. The potential for recorded music was soon realised and the new process was coined Full Frequency Range Recording (ffrr). Francis Attwood, the Company's advertising manager, came up with the idea of ffrr emerging from an ear – the birth of the famous logo.16

The first music recording using the new process was made at the Kingsway Hall in London during May 1944, heralding a new era in recorded sound. Sidney Beer conducted the National Symphony Orchestra in a performance of Tchaikovsky’s Symphony No.5 in E minor, Op.64.17

Haddy recalled that the first recording was rejected and had to be re-recorded. The waxes were sent from the studio to the pressing plant at New Malden on 6 June 1944.18 The recording was released in November 1944 without fanfare although the December 1944 edition of the Gramophone carried a full page advert. In this edition the reviewer JPP noted that it was 'technically, a very satisfactory recording’.19 The official announcement for ffrr was not made until June 1945, by which time the Company had released numerous records using the new process.

The records were soon followed in 1947 by the Decola radiogram, designed by Harvey Schwarz, Decca’s chief radio engineer, which would set a new standard in sound reproduction. It had a lightweight pick-up and the first with an elliptical stylus.20

The post war success and reputation of the Decca Company and ‘Decca Sound’ was entirely attributable to countermeasures developed during the U-boat war.

HMS Graph (U570) provided a very significant contribution to the anti-submarine war effort and after the various trials and tests she was deployed on active service. However, maintenance issues and a lack of spare parts led to her being decommissioned and eventually earmarked for scrapping.

HMS Graph in the Clyde. IWM collection (A16040)

In March 1944 whilst being towed from Chatham to the Clyde she foundered on rocks at Coul Point on the west coast of Islay and was abandoned.

The sonobuoy proved to be an effective means of countering and overcoming the U-boat threat and helped to decisively shift the balance of power in the Allies’ favour. It was subsequently developed into a more sophisticated and technically capable device and an effective countermeasure in anti-submarine warfare, particularly during the Cold War era.

By the end of the war the Admiralty had established an extensive library of gramophone records with underwater recordings of every conceivable mechanical and animal noise in varying water temperatures and depth. It would seem that none of the records produced during the war have survived, only tantalising references in some of the surviving documentation. However, the Royal Navy Submarine Museum at Gosport has a collection of post war gramophone records covering many aspects of underwater sound.

The gramophone record provided the vital link between technical innovation and a chance encounter at sea. War often provides the catalyst and impetus for innovation and technological development. This was certainly true in the case of the Decca Record Company whose significant contribution in the development of recorded sound was the legacy of a prevailing military imperative.

Dr Tony Wakeford
Chairman
Friends of The National Archives, Kew, London

Notes

1. The National Archives, AVIA 42/22, outline proposal dated 18 May 1941. This was enclosed with Pye’s letter dated 24 May 1941.
2. Roger A. Holler ‘The evolution of the sonobuoy from World War II to the Cold War’, in U.S. Navy Journal of Underwater Acoustics, January 2014, pp.322-346..
3. The National Archives, AVIA 42/22, a contract with the RCA Manufacturing Company, Camden, New Jersey, was subsequently drawn up in October 1941.
4. The National Archives, ADM 1/15194 and AIR 2/12711, the development of sonobuoys.
5. The National Archives, AIR 15/584, the gramophone record set identified as D 16 series.
6. The National Archives, ADM 239/358, report on U570 (HMS Graph).
7. The National Archives, ADM 1/15192, a 54 day programme of operational sea-going trials was undertaken beginning in February 1942, including making sound recordings. A sound trials report can be found in ADM 204/2215.
8. British Library Sound Archive, C90/08/01. Harvey Schwarz interviewed by Laurence Stapley, Oral History of Recorded Sound Series, 1983. Schwarz was Decca’s chief radio engineer.
9. British Library Sound Archive, C90/16/01, Arthur Haddy interviewed by Laurence Stapley, Oral History of Recorded Sound Series, 1983.
10. British Library Sound Archive, C90/21/01, Kenneth Wilkinson interviewed by Laurence Stapley, Oral History of Recorded Sound Series, 1983. Wilkinson was a recording engineer who worked with Haddy.
11. The National Archives, ADM 1/15152, Decca Navigational Aid. Reports and Trials.
12. Mike Ashman, 2015, 'When Hi-Fi Came of Age' in Gramophone, March 2015, p.20.
13. British Library Sound Archive, C1403/1, ibid. Haddy noted that the incidence of 'friendly fire' on British submarines was eliminated as a result.
14. The National Archives, ADM 253/478, High frequency sound output from submarines.
15. Barry Fox, ‘Hi-fi and the Second World War’ in New Scientist, 3 November 1983, p.356. Barry Fox interviewed Arthur Haddy about his experiences and contribution to recording sound at high quality.
16. Edward Lewis, 1956, No C.I.C., p.84.
17. Decca 12 inch 78s, K1032-6 and auto-coupled version AK1032-6.
18. British Library Sound Archive, C1403/1  [Decca Classcial, 1929-2009 by Philip Stuart, published in 2011,  states this recording was made on 8 June 1944 along with works by Grieg, Debussy and Delius. The second movement had been recorded experimentally on 12 May 1944]
19. Gramophone, December 1944, pp.i and 81-82
20. British Library Sound Archive, C90/08/01, ibid. Around 5000 were sold, retailing between £200 and £500, depending upon the model. The full potential of ffrr would become fully apparent when the first vinyl long-playing records were introduced in June 1950.

This is an edited version of the article that appears in Magna, the Friends’ magazine, and is reproduced with the kind permission of the trustees.

ffrr at 75

On 8 June 1945 Decca released their full frequency range recordings to the record buying public. It was exactly a year since Decca started recording in ffrr and during  that year they engaged Sidney Beer's National Symphony Orchestra to make recordings in ffrr.

To mark the 75th anniversary of the advent of ffrr we are releasing four albums by the National Symphony Orchestra during March and April.

Read Brian Wilson's article.