In the 1990s I used a full AVA FET-Valve system driving the B&W 801 Matrix Series II with the Van Alstine crossover mods as my reference system. I did the mods myself based on Frank's instructions in Audio Basics. In a moment of weakness, I sold the B&Ws, regretting the decision almost from the moment they were gone.
I'm sure Frank's electronics are better now than they were then, and even then they made the B&Ws sing. While I chose to "move on" to other electronics as well, not all moves are up in performance, as you know, and I might well return to AVA products someday. They certainly were extremely high value for money when I owned them, and from what I've heard from the newer products, as well as heard others say, they still are.
I've read this thread with great interest and learned a lot about products I did not know much, if anything, about. Frank’s criteria are quite tough, actually. Six thousand dollars sounds like a lot of money, but in today’s market, to get a truly full range speaker that clearly exceeds the performance of the B&W 801 Frank is working with is not as trivial as it seems. For one thing, bass extension at fairly high volume and low distortion seemingly is no cheaper in inflation-adjusted dollars than it used to be.
That said, here's my general guidance to for Frank, who admits to being a bit of a hermit.
1. If you plan to sell or at least recommend the product to your customers, you want a product whose manufacturer is financially stable and can actually deliver his goods within a reasonable amount of time. You want a company which can deliver its products within the same general time frame as you can deliver your electronics. This is basic for customer satisfaction, in cases of system buyers.
2. Before you get in bed with any speaker manufacturer, no matter how nice a guy he is, check out his financials with Dun & Bradstreet and contact his dealers to see what kind of relationships they enjoy from a business standpoint. If the manufacturer has no, or few, dealers, consider well whether this is a plus or a minus. If a company has been making speakers for years but only has a few dealers and does not profess to want it that way, what does that imply?
3. If there are any other audio electronics designers you are friendly with and whose work you respect, I suggest you contact them to see what speakers they use as references for their design work.
4. Similarly, if there are any audio reviewers whose views you respect, find out what they use as their current relatively affordable reference. A reviewer who has been reviewing products for a long time has extended experience with far more speakers under controlled circumstances than the average audiophile or the average manufacturer.
5. You want a speaker which has a well-defined frequency balance. If all frequency ranges are adjustable, then how can you tell what your electronics really sound like in terms of balance?
I'm afraid that eliminates the VMPS RM40 speakers from the running. While I have heard these speakers sound very good in dealer auditions, everything about them is adjustable over a fairly wide range, from the lowest bass and bass Q (adding or removing putty from the passive radiator) to the highest treble. The level controls for the upper ranges have a very wide range, are not marked for reference level, and very small rotations have significant effects on the sound. I seriously doubt that most users even have a "matched pair" as you would understand that concept. Also, the RM40 design is a moving target, constantly changing, the latest change involving the addition of a constant directivity waveguide which will necessitate a complete crossover overhaul. Do you really want that kind of speaker design as a design reference for your electronics?
Besides, from the RM40 and RM/X auditions I've had, both speakers have significantly leaner midbass and lower midrange sound than the B&Ws you are used to. If you like the generous warmth of the B&Ws, you would probably not like the VMPS speakers.
The Legacy Focus 20/20 is one you should hear. It's overall balance and midbass/lower midrange generosity is more in line with what you would expect. In my opinion, it is fully the equal of the VMPS RM40 in overall performance, it has much higher sensitivity, and will play louder for those who want to listen at live rock concert levels.
http://www.legacy-audio.com/2004/focus2020.html 5. Perhaps you should consider springing for the current B&W 801D at $16,000 a pair as your design reference. Yes, it's far above your price range, but the current B&W line has good products at much lesser prices which you could recommend to customers. The 801D has a 15" woofer, a cabinet at least as big as the 801 you're using, it is rated to go lower than the 800D by B&W and is self admitted by B&W to be fuller in the bass than the 800D. It could just be exactly what you are looking for, albeit far above the $6,000 limit you stated. B&W speakers took a detour for many years in terms of their high frequency balance, but with the new diamond tweeters now have a high end fully competitive with the best. The limiting factor of the B&W is the Kevlar midrange, but even it is vastly improved over earlier versions.
http://www.bwspeakers.com/index.cfm/fuseaction/products.models/Label/Model%20801D6. I think you definitely should audition the SP Technology speakers, just because the designer is clearly a level-headed engineer like you. I have never heard any of Bob's speakers, but now I want to. The discussion of his designs on his Web site and in this thread is exceptionally coherent and I am in tune with his world view.
7. That said, beware of speakers aimed at the current professional audio market. This market is driven by the needs of pop and rock music studio engineers for high SPLs and what passes for "dynamics," which usually means "startle factor" on hugely loud transients. There is a lot of talk about "chest crushing" bass. When did you last feel bass crush your chest in a concert of live, unamplified classical or jazz music? It doesn't happen. It happens at rock and pop concerts because that's the kind of bass that PA speakers produce at extremely high volumes. Do you want your design reference speakers to sound like PA speakers? Such speakers often cannot reproduce string or woodwind tonality to save their designers' skins and fail to reproduce subtle nuances at the other end of the dynamic spectrum at any sane volume level. There are exceptions, of course, but if the designer does not use the sound of unamplified classical music in a good hall as a reference, you are moving far from the sound of the B&Ws you know and love. Consider yourself warned.
8. You can buy a slightly used pair of most any speaker you want on Audiogon for no more than half its new price. If you can't find it there today, just wait a month. Audiophiles change speakers like they change socks. How else could the cottage industry that is high-end audio support many hundreds of speaker manufacturers headquartered in the United States alone?
9. Finally, and this is really an aside given your goals, if you'd enjoy reading about a labor of love, speaker-design wise, spend some time at Siegfried Linkwitz' Web site. I say, "some time" because it would take a long time indeed to explore all the highways and byways of that site. The Web site is as much a labor of love as his speakers appear to be. While his Orion speakers do not meet your requirements at all (they are actively quad-amped with a proprietary electronic EQ/crossover and use dynamic drivers in a dipole configuration), I think you will come away with respect for why he is doing what he is doing with that speaker, and for how affordably he is making these available to the public.
http://www.linkwitzlab.com
