|Confessions of an Amateur
(and sometimes pro) Speaker Builder
I've been building speakers for thirty years. I've been a hi-fi fan since the late 1960s when I was a young teenager. Not having much money, I would pore over copies of Stereo Review, Audio and High Fidelity, dreaming of having a really great system. I started out by buying surplus factory-second cabinets that were meant for the popular Advent Loudspeaker. I bought some CTS 10" woofers from McGee Radio and a pair of Phillips dome tweeters, put them together and I was on my way.
In the late 1970's I was living in Boston, the heart of the American hi-fi industry. In fact there was the famous "Boston Sound" engendered by the many speaker companies started by the irrepressible Henry Kloss, the founder of AR, KLH, Advent, Cambridge Soundworks and most recently Tivoli. By this time I had built a little side business building and selling my speakers by word of mouth. As luck would have it, my girlfriend was studying electronics and one of her classmates, Dan Loffreda, was looking for someone to run a small speaker company that he was involved with. This was AEI, or Audio Engineering International, a company originally founded by Roy Cizek, a blind trumpet player and hi-fi guy. Dan worked for a community development corporation that had funded AEI. Things weren't going so well and his people knew nothing about speakers or the hi-fi world, so I got a chance to fulfill a dream. At AEI I found an assembly line where we made our own woofers, a large supply of finished cabinets, boxes of tweeters, tools and big problems characterized by large debts and a cutthroat market. I got to know future New Hampshire Senator Warren Rudman since he was working for a law firm that represented our cabinet supplier to which we owed quite a bit of money. He would call me every day just to remind me. He was always courteous and respectful, despite the onerous task. I had fun experimenting and building the speakers (I was the only employee) and I learned quite a lot about the nature of the retail hi-fi business. We had a dealer that had ordered a lot of product from us only to stiff us on the bill, a very common practice in those days. If they had paid us, we could have paid Warren's company. So it goes. I spent the better part of a year at AEI and while it was heart-breaking, I learned a lot and had a great time. by the end, I was paid in speaker parts.
After AEI bit the dust, I got a job in the engineering department at HH Scott, a venerable company that had been bought after it failed following the Quadriphonic debacle of the early 1970s. There I met Peter Globa, Scott's speaker designer a Russian man with great love for his work, a keen sense of the "rightness" of a design and the ability to make the philistines in the front office do the right thing. I got a chance to do some real design and development work on some prototype high-end power amplifiers which performed very nicely. The times were changing, however and I left Scott to work in the computer field where I have been ever since.
I have always been partial to Henry Kloss' acoustic suspension design of speakers in which there is no port in the cabinet. The enclosed air acts like a spring, resisting the movement of the woofer. This design avoids the problems of having to tune a cabinet to a woofer and results more often in a less "boomy" bottom end. For years I have been concentrating on small speakers using the excellent small woofers that have been coming out of Scandinavia. A co-worker of mine who is also a hobbyist was building a set of transmission-line speakers using a very nice (and expensive!) woofer from Scan-Speak. That's where I got the notion that it was time to try something new. I had been wanting to build a tower speaker using the small woofers that I had come to trust for their accuracy, but the internal volume of such a large cabinet would have caused problems so I never did. A transmission-line design, however, would require a large volume in order to fit the entire folded line. So I cooked up the design you find here. Frankly, I didn't spend a great deal of time on it. There was only one bit of math and I value designs that are easy to build which explains why all the major pieces are 8" wide. But I knew that the Vifa components I was using were capable of very accurate sound reproduction and I figured that if the design didn't work out, I could recycle them into one of my small-box designs. That's what drove me. Forgive the pun.