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as reviewed by Roger S. Gordon
The Sirens of Greek mythology lured sailors to their deaths with seductive songs. Single-ended triode amps are their modern day equivalent. Many audiophiles who hear an SET amp in a properly set up system are seduced by the sound, and spend the rest of their audiophile lives in pursuit of the song of a single vacuum tube!
Single-ended triodes, though not common in the mainstream audio industry, have a fairly large niche in the audiophile world. Many of the exotic amps coming from Japan are SETs. Much of the activity in the DIY world revolves around single-ended triodes and the high-efficiency horn loudspeakers that are necessary to hear the glories of a low-powered SET. Low power is the bane of single-ended triode amps. With only a single vacuum tube as an output device, an SET amp is limited in output—most have 5 watts or less. Many have less than one watt. If you only listen to unaccompanied female vocalists, small jazz ensembles, or string quartets, the power limitations of an SET amp are not too restrictive, but if you are a headbanger or like Mahler’s Symphony of a Thousand played at realistic sound levels with thunderous bass, a single-ended triode amp will not be a satisfactory choice unless you have very efficient loudspeakers (96dB or greater) and a separately driven subwoofer. High-efficiency loudspeakers have traditionally been horns. In recent years, high-efficiency non-horn loudspeakers have become available from companies such as Cain and Cain and Omega, among others. I have heard many of these speakers at shows, and none have impressed me enough to make me want to take them home. It isn’t that they were bad speakers, but they simply didn’t have the qualities that rock my boat. Because single-ended triode amps could not drive the loudspeakers that I like—the ones that DO rock my boat—I pretty much ignored them. That all changed at CES 2003, when I walked into the deHavilland Electric Amplifier Company room at T.H.E. Show.
The system consisted of a deHavilland preamp and a pair of deHavilland single-ended triode amps driving Alon Lotus Elite Signature loudspeakers. I found the sound captivating, and ended up giving the deHavilland room my award for Best Sound of Show. The Alon speakers used in the deHavilland room were also used in two other very good-sounding rooms. Was the sound in the deHavilland room due to the speakers or the amps? The only way to know was to get a hold of a pair of deHavilland amps and try them in my system. That was easier said than done. deHavilland currently makes two SET amps, the 845-G and the GM-70, both named after the output tube they use. Both are monoblocks. The 845-G has 30 watts of power per channel, the GM-70, 50. By single-ended triode amp standards, this is an incredible amount of power. Both amps are selling very well, with a backlog of orders, so getting a review sample from the factory was impossible. My bid to hear the deHavilland amps under controlled conditions was thwarted.
At VSAC 2003, I ran into a deHavilland owner who was interested in selling his amps. He owned the predecessors to the 845-Gs, the Aries 845s, with the optional stepped attenuator volume controls. These amps had been upgraded by the deHavilland factory with 845-G circuitry. They still looked like Aries 845s, but sounded like the amps in current production. In December, the amps were shipped to me on approval. One was dropped during shipment and had to be returned to the factory for repair. Arrggghhh! After almost a year, I had finally gotten the deHavilland amps into my house, yet I couldn’t listen to them. I was so frustrated that I listened to mono recordings played on one speaker, using the only working deHavilland amp. It sounded pretty good.
CES 2004 rolled around, and the deHavilland room was now at the Alexis Park. There, a deHavilland-modified Ampex tape recorder played prerecorded commercial tapes through the deHavilland UltraVerve preamp with the GM-70 amps again driving Alon Lotus Elite Signature speakers. The sound was the closest to live music that I have ever heard from a two-channel stereo system—truly amazing.
Ten days after CES 2004, the repaired amp arrived. Finally. I hooked both amps to my VMPS FF-3 speakers and started to play music. Wonderful music. Everything I played—classical, rock, folk, vocal, ensemble, etc.—sounded wonderfully musical. After about twenty hours of playing time, I decided that the amps had had enough burn-in and it was time to start serious listening. One of my concerns was whether the 30-watt-per-channel output of the deHavillands would be enough to drive my speakers. The FF-3s, while fairly efficient at 89dB/watt, need a lot of current to drive the bottom end. When I purchased the FF-3s, I had to sell my 150-watt-per-channel solid state amp because it did not have enough current. I then purchased a 60-wpc Balanced Audio Technology VK-60 stereo tube amp because I had heard a pair of VK-60s, bridged to mono, doing wonderful things with the FF-3s in the VMPS room at CES. A single VK-60 sounded every bit as good driving the FF-3s in my living room. A few years later I traded in my VK-60 for the 75-wpc BAT VK-75se, a significant upgrade in dollar terms ($4200 versus $8500) but more than worth it in improved sound.
Could the deHavilland handle the bass? I played recordings with significant bass, slowly cranking up the volume. When I got to Reference Recordings RR-58, Pomp & Pipes, I heard the amps clip for the first time. It was fairly polite clipping, nothing ghastly, but clipping nevertheless. In the deHavillands’ defense, I had the volume louder than I ever play music. It was so loud that my wife was hiding behind closed doors upstairs. Had she been in the living room, we could have communicated only by screaming at each other. Keeping the volume control in the same position, I played numerous other recordings. No clipping—none—even at this abnormally high sound pressure level. Apparently, the combination of deep organ pedal note, bass drum, and brass, all playing ffff at the same time, is something the deHavilland, like many other tube amps, does not like. So my first question was answered. Yes, the deHavilland could drive the bottom octave of the FF-3s, provided I didn’t try to achieve sustained volumes significantly above concert hall levels.
For my next series of tests, I tried to ascertain the quality of the deHavillands’ bass, midrange, and treble by playing a number of familiar vinyl recordings: Ian & Sylvia, Northern Journey (Vanguard VSD-79154, Cisco reissue), Johnny Cash, Cash (American Recordings 45520-1), Whitesnake, Whitesnake (Geffen 7599-24099), Paul O’Dette, Tedesco della Tiorba (Harmonia Mundi HMU 7020), Professor Johnson’s Astounding Sound Show (Reference Recording RR-7, 45 rpm), Malcolm Arnold, Eight English Dances (Lyrita SRCS 109), and Saint-Saens, Symphony #3 (RCA LSC-2341, Classic Records 45 rpm reissue). I also listened to a number of CDs and SACDs on my heavily modified Sony SCD-1 (Modwright Absolute Truth Mod, Richard Kern transport mod, SuperClock II, and SuperClock II power supply), but, to my ears, the best vinyl gives a more detailed, more natural sound than the best CDs or SACDs, so I do most of my critical listening with vinyl.
The result of multiple playings of these LPs was that there was a significant improvement in the bass and midrange. I was hearing bass texture and timbre that I had not heard before. A plucked or bowed double bass was a joy to hear. So much detail! When the orchestral growled, I heard a snarling growl, not a polite or toned-down growl but a real snarl. It was more like what I hear in the concert hall than I had ever heard from my audio system. As for the midrange, single-ended triode amps are known for their seductive midrange, and the deHavillands’ midrange is very seductive. Listen to any female vocalist and you will be seduced—liquid, smooth, clear, natural, pick your adjective, it was there in spades. How was the treble? I am a middle aged male whose hearing starts to roll off at 14 kHz, or so the frequency tracks on my test CD tell me, so I am not the person to tell you about how the deHavilland sounds at 20 kHz. However, bells and triangles shimmered realistically. There was air and space surrounding all of the instruments, if it was on the recording. This indicated to me that the treble was just fine, so on to the next test—how would the deHavillands stack up when compared with the VK-75se?
I put the VK-75SE back into the system and let it warm up for over an hour. Onto the turntable went Northern Journey. What had been musical was now cold and analytical. The soundstage was wider and deeper, the sound emerged from a blacker background, and instruments and singers were more clearly delineated in three-dimensional space, but the magic was gone. What had been foot-stomping, fun music was now just music. I played the other records, and it was the same story. The more intimate the music, the greater the loss. I called an audiophile friend and asked him to come over. He had owned VMPS FF-3s and VMPS FF-1s speakers, which he had driven with a pair of bridged BAT VK-75s, and he still uses a BAT preamp. He arrived while I had the deHavillands in the system and was again playing Northern Journey. We listened to a couple of cuts, then I put the VK-75se into the system. After five seconds, he turned to me and said words to the effect of "You are kidding." I then put back the deHavillands. We played a couple of tracks from the Astounding Sound Show LP, then put the VK-75 back in and replayed the same tracks. After nearly two hours of swapping and comparing, my friend’s conclusion was identical to mine—I had to sell the VK-75se and buy the deHavillands.
To an audiophile—a person concerned with the reproduction of sound—the VK-75se is the better amp. If you went down a checklist of all of the attributes that an audiophile listens for in a stereo system, the VK-75se would score better than the deHavilland in almost every category. However, to music lovers such as myself and my friend, music is not about sound but emotion. It touches your soul. It makes you happy. It makes you sad. Live music brings tears to my eyes, and that is what I want to recreate in my home. The deHavilland communicates the joy of music. What more needs to be said? All of the scientific—audiophile—attributes at which the VK-75se excels are meaningless.
I did attempt to talk myself out of buying the deHavillands. I told myself that retubing them would cost a fortune. Granted, they have only three tubes per amp, but I reasoned that the humongous 845 output tube would to be very expensive, and that NOS 6AU5 and 6SN7s couldn’t be cheap. Wrong. The 845 is in production in China, and costs $39.95 on the web. NOS 6AU5s are $7.95 with significant discounts if you buy them in quantity, and the NOS Sylvania 6SN7s that deHavilland prefers are $20 to $30, while Electro-Harmonix 6SN7s, which sound almost as good, are $12.95, and I have been using them since the amps arrived. Retubing costs less than $60 per amp! Also, the factory informs me that current owners have been running their units for over four years without replacing tubes. In addition, Kara Chaffee, the chief designer for deHavilland, told me that swapping the 845s for NOS ones does change the sound, but not necessarily for the better, which is frightening when you consider what NOS 845s sell for. Swapping 6SN7s is a much more affordable way to tune the amps.
So, four weeks ago, after valiantly struggling against the impulse, I bought the deHavillands and sold my VK-75se. Buyer’s remorse should have set in by now, but it hasn’t. In fact, as I continue to listen to music through the deHavillands, I am even more convinced that I made the right decision. What really convinced me was my wife. As I was explaining to a frequent visitor to our home why I exchanged the visually striking, exotic looking VK-75se for the more sedate looking deHavilland, my wife interjected that the deHavillands sound so much better. You have to understand that my wife is not an audiophile. She does not even listen to music, nor does she attend concerts. When I play my system, she goes into another room and closes the door, yet she told our visitor that even from the next room she could clearly tell which amp I was playing during my comparisons. With one amp, it sounded like real musicians were playing in the living room, and with the other, there were no musicians. I could not have said it better. If you are a music lover, you need to listen to the deHavilland 845-G single-ended triode amps. They may rock your boat as they did mine. Roger S. Gordon
Electric Amplifier Company