Bob Carver: Carving a Name For Himself
Which brings me to 46-year-old Robert W. Carver: a physicist by training; the founder of two successful multi-million dollar consumer electronics companies, Phase Linear and Carver; the creative electronics engineer, termed a "genius" by some for his "Magnetic Field Power Amplifier," "Sonic Hologram Generator," "Digital Time Lens," "Asymmetric Charge-Coupled FM Detector," and "Auto-Correlation Noise Reduction System"; and an always controversial figure, with his "Carver Challenges" first tripping The Audio Critic magazine, then Stereophile, as Bob tried to show, with some subjective success, that at least with a hand-tweaked prototype, he could match the sound of one amplifier to that of another. "Transfer Function Matching" he called the process (footnote 1), and whether or not the Carver company could repeat the feat on the production line proved to be the crux of an intense public debate in these pages back in 1987 (footnote 2).
As Dick Olsher outlines in his review of Carver's Amazing Loudspeaker elsewhere in this issue, Bob Carver visited Santa Fe in September 1989 to carry out some urgent redesign on the product. I took the opportunity of his visit to try to pin him down over brunch both concerning the organizational changes that occurred last Summer at the company that bears his name, and about his design philosophy. My first question involved Bob's changing role at Carver following a severe drop in sales of almost $5 million to $20.5 million in 1988, a drop that led to a painful operating loss of $1.3 million (footnote 3).
Bob Carver: Since the inception of the Carver Corporation, I've been holding down two jobs, one by day and one by night. My daytime job has been president and chief executive officer, and my night-time job has been circuit designer. And inventor. The company has 275 people now, and the scope of both jobs has grown. I asked a friend of mine who's been on our board for many years to help me out and come take over my daytime job so that I could move my nighttime job up to the daytime. And to my great fortune he said yes, indeed he would do that.
John Atkinson: Basically, your role as administrator for a 275-strong workforce, coupled with the strategic running of the company, became a full-time job; it wasn't leaving you the time to devote yourself fully to product design.
Carver: That's right.
Atkinson: Last year you also hired Mark Friedman, one of the forces behind Onkyo's success in the US, to be your Vice President of Marketing and Product Development. I understand that Mark's feeling was that the Carver Corporation's problems basically stemmed from its product line suffering somewhat from staleness. The company had not adhered to the conventional consumer electronics "wisdom" of introducing a new line of products every year.
Carver: That's an understatement. Our products had gotten tremendously stale. For example, my 4000 preamplifier is over 15 years old. It was first introduced in 1974 as the Phase Linear preamp, and then resurrected when I formed Carver Corporation. It's been in our line ever since, and was only discontinued last year. That's a long time for a preamp to exist. And that's just one example. Over the years I've introduced new products with some special technology that the marketplace has liked a lot, but I stopped doing that about two years ago. With the result that we failed to bring out new products.
Atkinson: For a while in the early '80s, it seemed that every year there would be some new concept introduced which materialized as one or more Carver products. But couldn't you argue that, in fact, the 4000 preamp remaining in production all those years conformed to a good American tradition: "If it ain't broke, don't fix it."? Does a large company like Carver really need to introduce new products on a regular basis to retain its customers' interest?
Carver: I believe that all companies have to introduce new products to retain interest...new products and new technologies are the life blood of any company, and a failure to introduce new technologies is a failure to fulfill a company's destiny and, of course, the destinies of the people that make up the company.
I also became involved with loudspeaker design, and I'll tell you something about designing loudspeakers. It's worse than cocaine, in the sense that once you start it's hard to let go, and you end up working till two or three in the morning, ignoring life, ignoring family. It's almost a compulsive sickness. In the process of doing that, I didn't bring out the new products that I should have. So this last year I've made up for lost time and introduced 24 new products.
Atkinson: One of them, of course, was the C19 tube preamp. That's the second tube product we've seen from you, the first being the Silver Seven power amplifier. Does this represent a new-found passion, or have you always been interested in tubes?
Carver: I started designing amplifiers when I was in the 7th grade. Transistors hadn't arrived on the scene, so all my early work was designing vacuum-tube amplifiers. My first passion is vacuum-tube amplifiers, I grew up with vacuum-tube amplifiers. I love vacuum-tube amplifiers, I love them to pieces. I had a fantasy amplifier that I carried around in my mind all of these years; I dreamed about it, on and off, through my military career, through my children being born, through being married. I even purchased some Acrosound A-450 output transformers in the early '60s; I've carried those transformers with me all through my life, waiting some day for the moment to arrive to put them to use. The Silver Seven is that Fantasy Island amplifier, but I never really had the time to do it until now. The basic topology of the circuitry, however, was really hatched years ago.
A secondary reason for the development of the Silver Seven was that I really did want to endow an amplifier with everything that I could possibly think of, or anybody else could possibly think of, that would make it a wonderful, wonderful amplifier. And that included the silver wire and the Wondersolder, the gold connections inside...I've done a series of converging experiments, the results of which teach me that copper wire may well be equivalent to silver wire. But I'll tell you, in the case of the Silver Seven, if there was even the remotest possibility, unseen by me and undetectable by me, that silver would be better, I know one thing for sure: There's no better wire than silver wire!
Atkinson: Are there passive components where you have more definite feelings, where you have found that a more expensive construction or material does equate with better performance?
Carver: Absolutely. For example, if the power transformer is small and inexpensive, its performance won't be nearly as good in terms of thermal capacity, in terms of current capability, in terms of mechanical noise. But if it's a nice big one, expensively potted, vacuum impregnated, and so on, absolutely.
Atkinson: When you last visited Santa Fe, I remember you saying that output-transformer design is a black art. When you were conceiving the Silver Seven project, I understand you discussed transformers with people like David Hafler, who's been around since the golden age of tube amps.
Carver: David taught me how to design an output transformer. I had tried to design one myself and it had a bandwidth of 2kHz! Now, a successful audio output transformer requires a bandwidth of a quarter of a MHz if you want to close a feedback loop and make it stable. I talked to many people and I obtained examples of tube audio amplifiers, and I concluded that it was a lost art. Take a look at one of the nicest tube amplifiers around (save my own): the Jadis, say. Its output transformer is horrible at the high endnothing to do with the way it sounds, but on a measurement basisit's terribly flawed. I found out that the only guys that really seemed to know what was going on in output transformers were the guys that had been around for a long time: Bill Johnson, Sid Smith, David Hafler. It now seems to be coming back, however. The young guys are relearning how to make an output transformer for vacuum tubes because vacuum-tube amplifiers are very popular. I love vacuum-tube amplifiers. I really do.
Atkinson: Would it be fair to say that designing the Silver Seven output transformers was almost as obsessive an activity as getting involved in loudspeaker design?
Carver: Oh no, the loudspeaker design took over two-and-a-half years, the transformer design took a few weeks. But only because I talked to David and he taught me. If I had to dope it out myself, it probably could have been as obsessive a project. But, the transformer that I designed is basically the teachings of David Hafler with my own unique modern twists. Mostly just making it huge and winding it with silver wire. And I didn't run it ultralinear. I run my output stage with fixed screen potentials instead of an ultralinear biasing.
Atkinson: So it's a little bit like an older Audio Research design. They would run the screen grids at a constant high voltage, regulating it with a series-pass tube.
Carver: Must have been really old ones. The new ones have swinging screens.
Atkinson: Is Carver making many Silver Sevens?
Carver: It seems to me we're making a lot. I started out making one, then there was a demandto my great surprisefor a $17,500 amplifier. So we made ten of them. And now this run I'm working on now is for 30 sets. (It takes four chassis each to make each pair.) I guess we're making about ten Silver Sevens per month.
Footnote 1: Vol.8 No.6.
Footnote 2: Vol.10 Nos.3 (pp.117126 & 206211), and 5, pp.1423
Footnote 3: According to a report in Nation's Business, September 1989.