Close-Up of deHavilland GM70 Amplifier
Vacuum Tube Valley VSAC 2003 Show Report
DeHavilland and Rethm created what became the favorite room of the SixMoons.com website, with a Teres Audio 255, Sony SACD, Metronome C-20 Signature DAC, deHavilland UltraVerve preamp, deHavilland GM70 monoblocks, and The Second Rethm speakers.
As in previous years, full-range and horn-loaded speakers dominated the VSAC. The full-rangers were Lowthers, modified Lowthers, or Fostex, usually with rear-loaded horns. Ron Welborne also exhibited the well-known front-loaded Oris horn system, which uses Lowther or AES drivers. Full-rangers elicit strong feelings in the high-efficiency fraternity; some folks will only listen to them, and others folks can't stand them. Very few folks are in the middle - both Lowther and Fostex drivers have a immediately distinctive sound, unlike any other type of speaker.
2nd Rethm (Full-Range Rear-Horn) 
Titan (3-Way Front-Horn) The Big Theater Horns are on the other side of the fence, represented at the VSAC by John Tucker's eXemplars, and Bruce Edgar's Titans (complete with horn subwoofer). The big Altec-based eXemplars are back and better than ever, thanks to re-introduction of the classic Altec drivers by Great Plains Audio. John takes the classic A7 2-way and ramps it to a higher level, with all-Tractrix horns, entirely new crossover, and stunning cabinetwork. John also designed the new eXception preamp, which features a 5670 dual triode as standard, WE 396A or 2C51 as an option, a 5965 shunt regulator, and MagneQuest nickel parallel-feed output transformers.
Bruce Edgar had his three-way Titan system (along with monster subwoofer!) dominating not just the room, but the entire floor of the hotel! One of these years we're going to do the obvious thing and recruit John or Bruce to provide the speakers for the auditorium listening sessions downstairs. Big theater horns really deliver the goods when it comes full-range dynamics in big spaces - they should, that's what they were first designed to do back in the Thirties!
Bruce's room is one the few where I took a spot of R&R and just sat down, listened, and enjoyed ... the choice of beautifully recorded classical music probably had a lot to do with that, after a steady diet of jazz-n-blues in most of the other rooms. Thank you, Bruce, for that moment of relaxation and conversation!
The direct-radiator school of speaker design was also seen at the VSAC, with Firefly Audio's version of Doc Bottlehead's Straight 8 gathering a lot of good comment from show-goers. Apparently the new deluxe tweeter is really something, and a substantial upgrade to a well-regarded speaker in the high-efficiency world.
Jim Hagerman was in from sunny Honolulu to show the top-of-the-line Trumpet and Cornet all-triode phono preamps, and the VacuTrace tube tracer. The latter item is more unusual than it sounds, since Tektronix curve tracers are becoming extremely rare, and the VacuTrace is one of the few ways to really get the goods on tube linearity ... or even see if the new tube actually matches the fifty-year-old RCA curves.
Jim's website has an extremely useful technical section - rather than the usual empty-suit marketing prose, this is a serious technical-reference site. There are sections with information about building your own burn-in generator, on reference RIAA networks, including building your own inverse RIAA network, design of snubber filters, and filter-design calculators. Lots of stuff, worth a visit!
Page Five
All Text and Photographs © 2003 Lynn Olson.