At its narrow end, the mighty horn is connected to a professional Technics quartz transcription turntable via a modified Thirties EMG Expert "sound- box". The records - for, unlikely as it seems, this really is a record player - are tracked by an arm fashioned out of brass by a trumpet-maker, which in turn houses a stylus cut from a thorn. You need thorns, you see, because steel is too hard, creating a cold sound, and a diamond stylus would etch right into the record and destroy the grooves. A thorn needle evidently gives added warmth, as well as moulding itself to the shape of the groove and thus creating the best signal-to-noise ratio.
As thorn is hardly the most durable of materials, it may take a number of needles before a satisfactory recording is made, with separate takes edited together to produce the final version.
The idea - and it's as big an idea as the horn itself - is to create the most faithful duplication possible of the process by which old 78rpm discs were recorded in the era before microphones were introduced.
Until electrical recording began to take over from mechanical reproduction in 1928, the artist would stand in front of a horn and sing into it, creating vibrations in a diaphragm, which in turn made a needle move. The result was a record of the sound cut into grooves on a disc of warm wax.
By making the playback follow the same logic as the original recording, the team at Nimbus think they have come up with the perfect method of re-mastering material for their celebrated "Prima Voce" series of early vocal recordings. This 100th edition has just been marked by a collection of very early Caruso material, most of it recorded in Milan between 1902 and 1904 for the Gramophone and Typewriter Company.
Though Nimbus's mastering is done digitally, with a configuration of microphones placed at the bell of the horn and wired through to machines in the control room at the back of the hall, in every other respect the set-up is a temple to the virtues of analogue sound. After seeing what goes on there, it's no longer possible to take seriously the complaints of hi-fi bores - that it all started to go wrong when digital technology came in . For the boffins at Nimbus it all started to go wrong some 50 years earlier than that, with the arrival of the microphone.
"You see, the whole basis of sound is mechanical," says Norman White, the chief boffin behind the Prima Voce series, and in his prime a singer with Scottish Opera for more than 25 years.
"We communicate mechanically, and it's all physical; even the way we hear is physical. There's an awful lot going for mechanical sound, and a lot of things happen mechanically that are difficult to explain. For instance, you can feel the movement of a singer across the floor. Before microphones, you had no volume control, so the companies would employ a floor manager to move the singer away from the horn and then push them forward again. They even managed to construct a trolley so that they could wheel them back and forth. Dame Nellie Melba's records, for example, are generally too harsh, because no one had the courage to tell her to move away." As the sight of the ferocious horn was evidently enough to frighten some performers, it was sometimes concealed by curtains.
The main problem for Nimbus lies in getting pristine copies of original 78s to record from, since you just can't get the quality any more. In Britain, it seems, you never could.
"It's like looking for the Holy Grail," White says, shaking his head doubtfully. "I don't believe there's been a perfect record made. To find them in perfect condition is almost impossible; the peaks of the sound have gone, because the steel needles people used destroyed the grooves as they played. Sometimes we use up to a dozen copies and edit between them, but you can really only do that if the pressings were made at the same time."
British grooves are almost always the worst, and the crackly "fried egg" sounds we have come to associate with 78s turn out to be largely a native phenomenon, resulting from cost-cutting exercises such as mixing prime shellac with grit. Norman White looks horrified as he contemplates this shameless practice. "In this country we tried to make records more durable, but didn't go to the expense of a final grinding as other countries did," he explains.
There are also numerous types of disc, each with its own eccentricities; vinyl has a quieter surface noise but less sharpness of focus than shellac, which has a correspondingly brighter sound - and that is sometimes a problem in itself. It would gladden the heart of any vinyl-junkie DJ to know that in the case of 78s, the music genuinely resides in the grooves, and that the material nature of sound is absolutely inescapable.
Accordingly, White searches the world for suitable cases for treatment, with the United States usually proving the most fertile terrain, where the logo of the RCA Victor Company provides a reassuringly reliable kite- mark of quality. On the afternoon of my visit to Nimbus, they were re- mastering records from the archive of the St Petersburg Museum of Theatre and Music, which its librarian, Ludmilla Motchalova, had brought over personally. "They're in reasonably good condition, superb condition by your standards," White says.
The proof, of course, is in the pudding. Sitting in the optimum position, right at the end of the horn - almost in the very belly of the beast itself - I waited for the needle to hit the grooves of a recording from nearly 100 years ago. The suspense was almost unbearable. When Adelina Patti - who began her career in 1850 - began to sing on the record, made in 1906, my ears prickled at the fried-egg sounds. Then, gradually, I begin to hear the remarkable vitality of her voice as she rolled her "r"s and shrieked out Spanish trills in a performance brimming over with energy. At the end, she reached for a high note in a bravura finish. The dynamic range was astonishing, and for once the cliche was apt: it sounded as though she was right there in the room with you.
White switched to a platter from 1907 by a Spanish tenor, Francisco Vignes, and it just got better. By the time, just for a contrast, he played a later, microphone-assisted (but still mechanically reproduced) recording by the Benny Goodman band from the Thirties, I was entirely ready to up sticks and move to Monmouth.
Unfortunately, to my ear the CD re-masterings, while they are good, don't quite manage to recover the majesty of the original, horn-blown, originals. For that, you'd need to have a monster horn in every listener's home.
Until then, you'll have to make do with the CDs. Unless, of course, you can get to Monmouth for the concert on 26 June, when Norman White will take the decks of the infernal machine and let the thorn hit the shellac one more time. If you can make it, I'll guarantee that it will blow you away.
`Prima Voce' Anniversary Concert, 26 June, 7.30pm, at the Concert Hall of the Nimbus Foundation, Wyastone Leys, Monmouth (01600 891090) tickets pounds 12/pounds 9 concsReuse content