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Positive Feedback ISSUE 1
june/july 2002

antique sound labs

AQ1001DT integrated

as reviewed by Francisco Duran, Dave Clark, and Victor Chavira


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ProAc Response 2 with Osiris 24" stands.

Monarchy SM-70 amplifiers (mono). Reference Line Preeminence lA passive line stage.

Musical Concepts’ Pioneer DV414 DVD Epoch VII Signature player. Taddeo Digital Antidote Two.

Superconductor+ interconnects and a double run of JPS Ultraconductor speaker cables.

Panamax power conditioning. BDR cones and Vibrapods.


one.jpg (6551 bytes)The Divergent Technology rooms at the 2001 C.E.S. were an audio candy store, filled with rack upon rack of beautiful tube equipment. To top it off, there were some pretty respectable speakers in the form of the Reference 3A line. In the middle of all of this was an amiable person doing business in an almost conductor-like fashion, Mr. Tash Goka of Divergent Technology. A few months later I was sitting in front of an integrated amp from one of Divergent’s product lines, the Antique Sound Labs AQ1001DT.

Antique Sound Labs makes quite a lot of gear, in a variety of designs and tube complements that would whet the appetite of any card-carrying gearhead. The AQ1001DT is all business. Three covered transformers are lined up at the rear. In front of the transformers are four KT88 output tubes. Standing guard in the front are four 12AU7s. The sturdy black faceplate holds the volume and input selector controls and on/off switch. Around the back of the amp are three single-ended inputs labeled CD, Tuner, and AUX1. I could have used another input. There are also six hefty gold-plated speaker binding posts, giving you the option of four- or eight-ohm taps. A detachable power cord socket and fuse holder round out the array.

One nice feature of this amp is the bias adjustment arrangement. The five-position knob (the first click being off) on the side of the amp clicks to each corresponding output tube, allowing you to adjust each tube with a screwdriver and your handy dandy voltmeter. Let’s not get lazy now, tube amps take a little work. I didn’t take the AQ1001DT apart to have a peek inside, but I can tell you that this is a solidly built amp, and it is very good-looking, with its chrome chassis and black accents. I heard no hums, pops, or buzzes while it was running, and believe me I put this amp through its paces. Once the tubes were burned in the bias held steady, and this little 50 watter had plenty of power to keep my speakers rockin’. It sat where my monoblocks usually sit, on an Osiris amp stand. I listen to solid state amps most of the time, with only an occasional one-night fling with a tube unit. I have grown accustomed to the virtues of solid state amps, these being extension at the frequency extremes and a quiet background, but there are times, especially with my ProAc speakers, that I miss the warmth, body, and liquid sound that only a good tube amp can bring. Nevertheless, whenever I listen to music through tube amps, the solid state spider makes himself comfortable on my shoulder and proceeds to whisper in my ear things like, “Where’s the bass, where’s the top end, and check out all that background noise!” For the most part, however, this was not the case with the AQ1001DT.

Whether it was the KT88 tubes or the circuitry of the amp, the AQ1001DT reproduced the whole musical spectrum without overwhelming me with background noise. Before I talk about the musical picture, let’s pick apart the sound of this amp, starting with the bass. I was quite surprised by the bass performance of the AQ1001DT. With most tube amps that I have had in my system, a certain amount of weight and extension is always missing in the bottom octaves. That did not happen with the AQ1001DT. Unless I shifted my attention to it, the thought of bass rolloff never entered my mind. Adjectives like “full,” “taut,” “extended,” and “fast” applied to the low end performance of this amp. It was easy to follow bass lines in the music, Pat Metheny’s Letter From Home CD being a prime example. I recently received two new CDs from the BMG Jazz Club, Clarence Gatemouth Brown’s American Music Texas Style and Keith Jarrett’s double CD, Whisper Not. Gate was really swinging through the AQ. The horns were full and rich. There was a smooth and coherent spread of sound in front of me. The midrange was not too lush or euphonic, and ah, the guitars. The texture and body of acoustic guitars was something no solid state amp could match. From Russell Malone and Grant Green to Luiz Bonfa, the sound of my favorite stringed instrument was thoroughly engaging through the AQ1001DT.

I can’t neglect to mention The Eddie Gale Quintet’s CD, A Minute with Miles, on Mapleshade. This is the best-sounding disc that I own. Through the AQ1001DT, the sound of horns had a slick, polished clarity. The trumpet was reproduced with as much realism as my system could muster. Another newfound musical treasure is the CD Neighborhoods, by Ulu Dara, which I recently discovered through the local public radio station. This is an eclectic mix of blues, folk, and R&B, and there is some fantastic storytelling going on, especially in the track "Red Ant." The music sounded, smooth, clear, and detailed without being overtly hi-fi. The midrange of this HDCD disc could have been recorded better, but the AQ caught the musical picture quite well. The excellent midrange performance also extended into the upper ranges. I didn’t notice any lack of extension or overt rounding off of the uppermost octaves. The highs were round, clear, and extended. The high frequencies were sweeter than with my solid state amps. They were also not as flat-sounding, and sibilance was a tad tamer. This was icing on the cake. What surprised me was that the top end of the AQ1001DT, although sweeter, was more open, extended, and detailed than with my amps. My Monarchys are slightly diffuse in the midrange. The AQ’s soundstage is very layered but natural, depending on the recording, of course. I could clearly hear way into the soundstage. Part of this is due, I’m sure, to this amp’s quiet operation. On the Ulu Dara CD, the shaker sound was downright eerie. When I walked around the side and back of my left speaker I swore that I was walking around someone playing a shaker. I have heard other amp/speaker combos do better, but these are the kinds of musical experiences that are evoked by this amp. I was better able to hear into the music, and small musical details were more easily heard than through my amps.

Another thing about the AQ1001DT is that it is receptive to changes in system configuration. I used it to evaluate power cords and the Balanced Power Technologies Isolators that we got in. It also saw duty in my re-evaluation of the Richard Gray Power Company units. Any such changes were readily apparent with this amp, as was a fortuitous tube swap. aM partners Dave Clark and the A.D. Banerjee swapped the four JJ 12AU7s that came with this unit for some NOS RCAs, and sent me the NOS tubes for a listen. Wow, talk about bringing this amp to a new level of performance, in terms of overall musicality, background silence, dimensionality, and inner detail. The NOS tubes made the top end noticeably more open, detailed, and clean, and the mids and bottom were more solid and real. NOS tubes are a must-hear with this amp if you want to wring even more performance out of an already excellent product.

The AQ1001DT gave the impression in my system of a well-balanced set of virtues. You know something is right when you don’t want to put your own gear back in your system. It is nice when an amp pulls you into the music and you just want to listen for a long time. I’ve never been one to fall for the “goosebump factor” BS. The only time I get them is when I’m in my truck rolling (or inching) down an L.A. freeway and a cool song comes on, but for some reason, with this amp in my system, you guessed it, goosebumps happened more than once. The AQ1001DT had the ability to connect me to the music right after turn on and it didn’t let up.

Before I sign off I have to relate a little story to you. When it was time to return this unit, I was asked to take it to Upscale Audio, which is a new local dealer for Antique Sound Labs. When Victor Chavira and I walked into Kevin Deal’s showroom, we were surprised to find a pair of Avantgarde Duo speakers hooked up to Antique Sound’s little MGSI15DT and the new Ajoe Tjoeb 4000 CD player. Here was a whopping $1200 of electronics driving a $14,000 pair of speakers! Victor and I were amazed, even flabbergasted at what we heard. Antique Sound Labs might not be as recognizable a brand as the top dogs here in the U.S, but that shouldn’t stop you from auditioning these fine-sounding, well built, and very reasonably priced products. Francisco Duran





Reimer Speaker Systems Tetons.

Clayton Audio M100 monoblock amplifiers. E.A.R. 834P phono stage. Blue Circle BC3000 preamp w/Tunsgram tubes, and BCG3.1 power supply.

EAD T1000 transport and EVS Millenium II DAC with Audient Technologies’ Tactic and Audit, and Taddeo Digital Antidote Two. Linn Axiss turntable with K9 cartridge and Basik Plus arm.

JPS Superconductor+ interconnects, digital, and NC speaker cables. Sahuaro Slipstream, Blue Circle BC63, Clayton Audio, and JPS Kaptovator AC cables.

PS Audio P300 Power Plant.
Dedicated 20 and 15 amp ac circuits. Shakti Stones and On-Lines. EchoBuster room treatments. BDR cones and board, DH cones, Vibrapods, Mondo racks and stands, Townshend Audio 2D and 3D Seismic Sinks, various hard woods, etc.


two.jpg (6646 bytes)Can you get a $12,000 preamp-and-amp combo for $400? No, but if you spend an extra $400, you can make a $1200 integrated sound almost as good as a $12,000 amp/preamp combo. How? Start with the Antique Sound Labs AQ1001DT integrated, a decent but not really musical-sounding 60-watt integrated that offers a big, ballsy sound lacking in refinement and subtlety. Then, replace the Chinese input tubes with NOS tubes. Finally, toss the stock AC cord and substitute one of higher caliber. (I used a PS Audio Lab, but the market is rife with specialty AC cords, so go hog wild.) By doing the above, I was able to turn a not-so-ugly duckling into a captivating swan.

Let me digress with my initial take on the AQ1001. I was the third aM reviewer to get the amp, and was certain it had been fully broken in. With the amp on a Target stand, and using some Nordost SPM interconnects, the AQ1001 had a wide but shallow sound field that was awash in two-dimensional images. These images lacked body, air, separation, and life. The music was "water-colored," without fine delineation or a defined space. Can the stock AQ1001 deliver the goods, allowing one to enjoy the music? The answer is a quantifiable "Yes," but only if soundfield and dimensional palpability are not as important to you as drive and rhythm, which the AQ1001 has in spades. No, if you want it all.

Bass was very deep and tight, with amazing slam for a 60-watt tube amplifier. The AQ1001 was not the least bit shy about presenting music with slam and bam! Music was exciting and fun to listen to, but not really all that "musical." Subtle shadings and nuances were omitted. Lost was the feeling that I was listening to real instruments or performers playing in a real space. The sound was more hi-fi than real-more like a what you'd hear at a rock concert than in a jazz club. This is not to suggest that the AQ1001 was sonically tilted in any direction. No, it sounded neither dark nor light, nor was it the least bit bass-heavy or bright. The mids were neither recessed nor pushed forward. But again, the amp was not musical, especially when compared to my amp and preamp.

Of course, I was comparing an entry-level integrated to two products attempting to push the envelope, but I kept saying to myself, "Not bad for $1200!" The stock AQ1001 is just not that refined. It is a fun product, but not one I could enter into a serious long-term relationship with. HOWEVER, for the fun of it, I borrowed some NOS 12AU7 tubes, and what an amazing transformation! Images now existed in a airy atmosphere that was very natural and alive. The NOS tubes really made things happen, and the same goes when I dumped the stock AC cord and used a PS Audio Mini-Lab Cable. Now things were cooking, so much so I was starting to feel a little put off by the fact that here was a $1200 integrated, with $400 in upgrades, putting my reference stuff to shame.

What the tubes and cable provided was everything that was missing before, but without sacrificing any of the AQ1001's strengths. Air, depth, musical subtleties, tonal nuances, and dimensional palpability were there, up the yahoo. I mean, what's the deal? I could sell my Blue Circle preamp and Clayton amps, buy the AQ1001, and with the leftover cash, go on a nice European vacation! I was bummed, but then, the AQ1001 was now so involving to listen to that I was too busy to be depressed.

The AQ1001 as delivered is a decent integrated that will serve you well if you are not too concerned with musical naturalism, but if you are, the stock tubes are not going to get you there. Changing the tubes and AC cord moves the AQ1001 into a completely different league, allowing it to compete with a combo costing many times more. Manufacturers of $1200 amps have to cut corners, and the choice of tubes is an obvious place to start. Why put expensive tubes into an inexpensive product, especially when most users are going to be tube-rolling anyway? When properly outfitted, the AQ1001 is a giant killer, and gets my strong recommendation! Dave Clark





Magneplanar 1.6 and B&W DM 302.

Anthem Amp 1. SCE Harmonic Recovery System.

Audio Electronics CD1 player.

Nordost Quattro-Fil interconnects, Blue Heaven speaker cables, and El Dorado power cords.

Monster Cables HTS 1000 AC center. Vibrapods, Lovan Trisolator, and Echo Busters.


three.jpg (8484 bytes)Antique Sound Labs is a Hong Kong-based company that has been making tube amps for many years. Their products are currently imported to North America by Divergent Technologies of Ontario, Canada. The 1001 is a 50 watt ultralinear push-pull amp with a passive attenuator that accepts up to three line-level sources. The tube complement is four 12AU7s and four KT88s. The unit is well constructed. With its tall black transformer towers, mirror-like chrome base, and brilliant glass tubes, the AQ is attractive and should inspire pride of ownership in its buyers. The unit also features nice touches like a removable power chord, 4 and 8 ohm transformer taps, and solid metal binding posts. A few words about setup and break-in. Whenever possible, we request components that have been broken in to shorten the loan period and increase the consistency of sound. Nevertheless, the AQ arrived fresh from the factory, and when first plugged in sounded horrible compared to my veteran Anthem Amp1. Since I was the only reviewer with a multimeter, I set the bias to its specified 45 millivolts and reset it after several weeks. With time, the AQ loosened up and began to show its true colors.

I listened to a wide variety of music through the AQ, and several recordings stand out in my memory. The Lion King Original Cast recording is a disc that my family enjoys listening to.The Los Angeles production is a true audio spectacle, with left and right percussionists flanking the stage, banging out contrasting rhythms on a vast array of hand drums and gongs.The song "Endless Night" is a moving lament sung by the older Simba to his absent father.The AQ captures the emotional essence of this tender moment. The amp demonstrated its excellent manners in rendering subtle dynamic contrasts. As the actor's voice soars from medium to loud, the effect is truly moving, just as I remember during the live performance. In my experience, tube components render the way a voice grows and projects more convincingly than solid state devices.

Another recording that sounded great through the AQ1001DT was A Latin Vibe!, a budget-priced Latin Jazz collection of vibraphonists from the Concord label. One track on this disc is Poncho Sanchez' slow rendition of "Morning."This laid-back tune was richly rendered by the AQ. Flute sounded relaxed, breathy, and dimensional. Vibes rang with metallic overtones. Horn players stepped out from behind one another and spread about the studio floor.In a word, the AQ1001DT gives everything one expects from a 50 watt push/pull tube integrated amp: warmth, body, and superb responsiveness, with long arches of sound. The similarities between the AQ and my Anthem Amp 1 are many. Both excel at portraying performances in real space.The AQ, however, basks music in a clearer light than the slightly off-white perspective of the EL34-based Anthem. Even though both amps barely meet the 1.6s' minimum power requirements, both serve up demanding material with satisfying levels of drama and scale.One obvious difference between the AQ and the Anthem is the AQ's input level control.This feature allowed me to effectively control the intensity of sound as opposed to using the less efficient digital attenuator on my CD player.

The AQ's strongest attribute is its picturesque midband.Even with limited break-in and stock tubes, the AQ presented a rich palette of musical colors. The amp is well built, pleasing to the eye, and much more versatile than my Anthem, and I haven't even touched on the issue of fine-tuning with driver and power tubes. With so many favorable qualities, the AQ1001DT is easily recommended. Victor Chavira




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AQ1001DT integrated
Retail $1199

Divergent Technologies
TEL: 519. 749. 1565
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