ONLINE - ISSUE 26
My Audio Experience: The Sound Quest SQ-84
Some time ago, while talking with Omega Loudspeakers' Louis Chochos, I asked if he had heard any simple, value oriented tube amps that partnered well with his new Superhemps. He directed me to the Sound Quest SQ-84 Amplifier. While the SQ-84 was only one of Louis' many recommendations, it seemed on paper to be an excellent pairing with the hemps and of course, any recommendation coming from him pulls some weight too, because Lou has a nose for great sounding gear at real-world prices.
The Sound Quest SQ-84 amplifier was designed and is built by Mr. Stephen Monte (of Nat Distribution/Quest for Sound) from selected parts sourced from overseas. Stephen had supplied a fine Consonance 2.0 Reference SACD player for a PFO review I wrote some ages ago ( http://www.positive-feedback.com/Issue13/consonance20sacd.htm ), so all it took was a quick email and an amp was sent right out to me. That was a very long time ago. Life can be a cruel mistress and due to a number of personal and professional commitments, my audio writing hobby was put on "indefinite hold". I had written a few notes about the amp, but as I age my aural memory is becoming as short as the hours in a day. I have struggled with how to face this dilemma, but since I did indeed enjoy the amp, I felt it proper to share what little info I could piece together. Therefore--and prefaced with a sincere public apology to Mr. Monte--I am distilling this audio experience down even further than I normally would. Onward audio-soldiers…
The Sound Quest SQ-84 is a push-pull tube amp/headphone amp designed around the 6V6 tube, which in my limited experience (which now includes the AudioTropic Music Machine), is a very nice little audio tube. Though smallish in footprint at 15 3/4" long X 6 7/8" wide X 8 1/4" high, the amp is a chunky 27 pound mini-beast. It is well built, with a "Retro-industrial chic" look. In fact, with tube cage installed, it would fit nicely sandwiched between an oscilloscope and a signal generator. The 84 employs a pair of 6U8 tubes to handle both input and driver duties and provides enough voltage gain to produce 10 big watts from a quad (one matched pair per channel) of 6V6 beam pentodes strapped into triode-mode and transformer-coupled to the load. The circuit uses a modest 6dB of negative feedback and is self-biasing. While the amp is only a single input, it does offer a volume attenuator so it can be used as an integrated amp for those with only one source.
A very nice touch (although one used only briefly by yours truly) is the addition of a headphone output on the front that can be alternated between speaker and headphone with a simple flick of a front panel switch. While my high-end headphoning days have come to an end, it sounded very, very good with my trusty-rusty Signets and my son's AKG K240s. Since I no longer have great cans in house, I will confine my comments to state that the SQ-84 is without question an excellent headphone amp and it may be a great one. The bottom line of course is that this option gives this amp an additional measure of value to those searching for a simple solution for both speaker and headphone listening.
The SQ-84 clearly has a voice of its own. It is a punchy, lively sound with excellent micro-dynamic abilities providing a danceable vibe that was always in evidence. There was an abundance of energy in the upper half of the musical spectrum that gave it a mildly tilted-up sound, but not so much that it ever bothered me. As long a prospective owner understands this flavor is part of the amp it could be a great opportunity to match speakers and components that could use a bit of waking up. Had I not already sent them off prior to getting the SQ-84, I bet the little Audio Note AX2 Signatures and Nola Minis would both be great mates for this amp. Both speakers have a slightly laid back nature that would, in my opinion, benefit from the Sound Quest's take-no-prisoners attitude. I felt the stock tubes to be a bit spitty and while the SQ is commendably quiet, it is not totally silent and I found careful cable routing to be extremely influential in quieting the unit to its lowest level.
In addition to being full of life, the amp is also subjectively powerful. The 10 tube watts pumped out by the SQ-84 really drove my 96dB/8-ohm single-driver Superhemps with authority. The amp would distort a bit when really pushed, but up to the breaking point it really rocked and was plenty loud for this headbanger. Bass is excellent—tightly deep and articulate—even more so when driving my REL Strata III subwoofer. The midrange is very good, but strayed toward the lean side at times with my gear. Treble extension is also very good; however I did note some graininess at in the upper registers. Although I was not able to try, I believed at the time a different set of 6V6 tubes might have helped ameliorate the grain and leanness that I heard. And while I clearly think changing tubes could have a quite positive effect, the value approach suffers when it is suggested that more expensive tubes must be rolled in order to influence an amp to perform up to its potential. That is not the case here, as I quite enjoyed the amp with the supplied tubes, but just as clearly, tubes—perhaps even some of the other inexpensive new issue brands—may banish these minor complaints.
The Sound Quest did benefit from the additional clarity and control provided by my AudioTropic Moebius preamp. I felt the same way about the Moebius/Music Machine combination too. And while my preamp seems to do some very good things for 6V6 P-P amps, it is not essential to have a fine preamp to enjoy the SQ-84. It never failed to get my musical juices flowing and I found myself playing all my old rock ‘n roll albums while it was here. I know I have made much of the SQ's vivacious manner, but that was my overriding remembrance of its sound signature. If the 84 errs on the side of rhythm and punch, it is in much the same way some tube amps homogenize sound with a rose-colored glow of smoothness. The Sound Quest highlights the leading edge of every musical note which "pops" with a high degree of dynamic contrast. I must say, it is an infectious choice of voicing as I found my foot tapping with nearly every musical selection played.
No doubt Mr. Monte has succeeded in building a relatively simple and fun-to-listen tube amp that also happens to sound very good. The Sound Quest SQ-84 may not be playing in the same 6V6 league as the awesome—and three times more expensive--AudioTropic Music Machine, but without question, it is a smartly dressed, solid performer that should give tube amps in the same price range a run for the money. As long as it is mated with speakers of appropriate sensitivity—Omegas, Audio Notes, or perhaps one of the many new low-priced horn speakers come to mind--the Sound Quest SQ-84 would make an excellent amp for any audiophile on a budget to build a nice system around. When all the positives are accounted for—small footprint, simple operation, built-in volume control, as well as being reasonably cheap to re-tube-it offers a high value even before considering its ability to drive top-flight headphones. So if you are a tube-o'-phile short on big-amp cash (especially `philes with nice headphones), only require one source and can live with ten rock n' roll watts to pump up the jams, this amp is one to audition and comes highly recommended.