If the title doesn't say it all, then let us remind you: The original Quad ESL. That display of genius which makes Peter Walker something of an audio deity. The most cherished hi-fi product ever. The cause of a thousand heartbreaks when its demise was announced. Call it the Quad 57 if you're innumerate, the Quad 55 if you're fastidious and did your homework, or simply call it the Quad Electrostatic Loudspeaker if you drink your whiskey neat and respect the designer's wishes. Or ESL for short. Whatever you name it, the Quad speaker system was the first commercially and sonically successful full-range electrostatic loudspeaker and - despite its inherent shortcomings - for many it remains the best.
Think about those shortcomings and how they never managed to prevent the ESL from garnering such praise and devotion. What were they? Restricted maximum SPLs and bass extension. But those with taste and a sense of proportion never minded. After all, this was a speaker designed for a market which consisted solely - however politically incorrect this sounds - of well-heeled, refined gentlemen. Invariably, they listened to classical music, were not headbangers and were bound by the source components of the 1950s. And, should they listen in massive rooms, or crave extra wallop down below, they merely did what any intelligent music lover would do: they emulated Alastair Robertson-Aikman of SME and used four pairs, one pair in each corner. Simple.
Peter Walker's Acoustical Manufacturing Company was nearing the completion of its second decade by the time the ESL arrived. The company already had an enviable reputation for its amplifiers - both pro and domestic - and even had a classy speaker in the form of a successful ribbon-hybrid, the horn-loaded Corner Ribbon Loudspeaker of 1949. But, following the appearance of a book in the USA in 1954, describing in scientific terms the superiority of the electrostatic transducer, Walker was inspired to develop an ESL of his own. Moreover, the appearance in 1949 of DuPont's Mylar finally meant that there was a material ideally suited to the requirements of an ideal electrostatic diaphragm.
After publishing three articles in Wireless World in 1955, the speaker was ready for production, appearing on the cover of the 1956 Hi-Fi Yearbook, the very first volume of that never-forgotten industry bible. Back in 1994, I was fortunate enough to talk with Peter, and I asked him about the speaker's origins.
A: Why did you move from the original ribbon speaker to what became the original Quad electrostatic?
PW: From a theoretical point of view, an electrostatic is an ideal way to make a loudspeaker -- it matches the air perfectly and it's all predictable, as ordinary loudspeakers are rather variable. It has some problems which are rather difficult, mainly due to the stretching of the diaphragm. It mustn't shrink and that sort of thing. Very high voltages, 10,000 volts make it difficult but it's an ideal - I think most loudspeaker manufacturers have looked at it and said, "What a lovely way to make a speaker but it's not very practical." And a lot of manufacturers have tried it, too, and most of them have said, "This is not profitable. Get back to putting loudspeakers in boxes and sell 'em, lad!" (Laughs)
I've always thought so, right from, oh, 1945 I suppose or thereabouts that an electrostatic would be a nice way of doing it. But it's in the back of your mind, how can you do it? And it had a lot of problems. But the ribbon was a very good way of getting very good high-frequency response - excellent.
The ribbon was a hybrid, [the ribbon itself] was very good from 2000 cycles upwards and the bass unit was very good up to 500 cycles. Not very good in the middle, which I can admit now, but there you are. During the ribbon speaker's life we sold less than a thousand units. It wasn't pairs, it was all mono; there wasn't any stereo then. And they were £95 a time which in present-day money is quite a lot.
Around the same time that the LP was introduced, 1954, 1955, the electrostatic was introduced - I think we demonstrated it in 1955, about that time.
A: How many years had you been working on it?
PW: Well, you don't work on it for years and years. You have a little go and get rid of a few problems, and then you forget that and get on with other things that you can make and it stays in the back of your mind and you think, "Oh, we could get over that -- what about dust and these high voltages?" And you think of another idea and go on a little bit more. And then you forget it again for a long time; you're not working every day on the same thing. It's like the ESL 63 loudspeaker. It took us eighteen years to develop but it wasn't eighteen years every day. (Laughs.) Not at all.
A: Were there any other, earlier electrostatics with which yours had to bear comparison?
PW: There was certainly the Janzen in the US. There was one before the war which was called the Primastatic, I think which was just a tweeter, several German electrostatics were made but the really didn't make a big market at all. None (Janzens) came to England unless you went over with a suitcase. The original ESL just competed against other loudspeakers, and it wasn't as loud, so people who wanted to shake the windows didn't buy a Quad electrostatic speaker.
A: Was it an immediate hit? Did the audio journalists of the time recognize it as revolutionary?
PW: Some of them did and some of them didn't. It was quite an oddball sort of thing. "What's this funny looking thing?" They thought it looked like a room heater. In fact, we'd have people stand by them to feel the warmth.
Read more of the interview on Page 2.