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Reviewer: David Kan
Digital Source: Restek Radiant, Assemblage D2D-1/DAC-3.1 Platinum, Micromega Microdrive, Deltec PDM Two DAC
Preamp: Symphonic Line RG3 Mk III, Restek Vector, Micromega Variodac as preamp
Power Amp: Symphonic Line RG4 Mk III, Sim Audio Celeste W-4070 SE, Nu Force Reference 9
Speakers: Apogee Centaur Minor; Klipsch Synergy F2; Mark & Daniel Maximus-Monitor, Omni-Harmonizer and Maximus-Ruby
Cables: Symphonic Line Reference interconnect, Clearaudio Silver Line interconnect, Deltec Black Slink interconnect, Luscombe LBR-35 interconnect, Unity Audio Solid Link interconnect (on loan), Symphonic Line The Fast speaker cables, OCOS speaker cables by Dynaudio, Unity Audio Solid Link single-wire/Shotgun bi-wire speaker cables [on loan], Orphee Audio digital cable, Aural Symphonic Digital Standard digital cable
Power Cords: Aural Symphonic Missing Link, Ensemble Powerflux, Unity Audio Link/Precision Link [on loan]
Power Line Conditioning: Tice Power Block IIIC, Monster Power HTS-3500 Mk II (modified by NuForce), Monster Power HTS-1000 Mk II
Room Size: A: 12' x 24' x 9' opens to 12' x 17' x 9' L-shape, short wall setup / B: 15' x 15' x 8' / C: 13' x 28' 8" x 9' with openings on one side to hallway and staircase, short wall setup
Review component Retail: US$749 | CAD $799

Reevaluating good value, refashioning old fashion
"Getting the most bang for the buck" has always been the catch phrase among budget-conscious audiophiles. Like any superlative claim, the most bang, especially in this highly debatable and subjective context called audio, should be prudently scrutinized in relative terms. While the recent influx of tube amps from China pushes the bang to ever higher decibels, the bang in the solid-state arena seems to be relatively muted. That's what makes this bang for the buck from Qinpu an attention grabber. The bang in this case is 100 watts x 2 (8 ohms) and the buck is all of $799 Canadian. The amp in question is the Qinpu A-1.0X solid-state integrated amp.

The name Qinpu, pronounced as tsin-poo, means tablature or instrumental notation for the guqin, which is an ancient Chinese stringed instrument like the zither and plucked by long fingernails. That's what most reviewers would tell you after consulting Wikipedia. For easy understanding and modern day's sake, let's call it piano score, since from my understanding of my mother tongue, qinpu in today's common usage does refer to a piano score. One way or the other, the name is symbolic of the musical inclination of the company. Speaking of which, the full name of the parent company is Guang Zhou CHPO Electronic Co. Ltd, Guang Zhou being the most important industrial commercial city in Southern China just north of Hong Kong. Established in 1998, the company manufactures and markets a wide number of electronic products in China for home theatre, karaoke, desktop HiFi and 2-channel audio including amplifiers, loudspeakers and loudspeaker drivers. However, for the rest of the world, Qinpu is mainly represented by two integrated amps: the A-8000 Mk II and A-1.0X.

Although having only two integrated amplifiers on its North American portfolio, Qinpu has received a lot of critical acclaim, including the 2005 Positive Feedback Online's Writers' Choice Award for its flagship model A-8000 Mk II. According to Bernard Li of Charisma Audio, Qinpu's Canadian distributor, the designer of Qinpu has an obsessive perseverance for amplifiers not exceeding 100wpc despite market demand because once exceeding that, he believes sonic quality begins to compromise. That explains why both Qinpu models are delivering exactly 100 watts x 2 into 8 ohms and no more.

Low-budget solid-state integrated amps have always been the turf of good old Brit brands like Arcam, Cambridge, Creek, Myriad, Rega, and Roksan, with keen competition from Rotel, NAD, Marantz and Onkyo. But none of them can match Qinpu's bang for the bucks - watt for watt, dollar for dollar. I did a quick 'dollar per watt' survey on low-budget integrated amps available in Canada and the findings were quite interesting:

Arcam DiVA A65 Plus 40 watts CAD 995 CAD 24.88 per watt
Rega Brio 3 49 watts CAD 795 CAD 16.22
Myriad Z140 50 watts CAD 1,295 CAD 25.90
Cambridge Azur 540A Version 2 60 watts CAD 499 CAD 8.31
Onkyo A 9555 100 watts CAD 999 CAD 9.99
Roksan Kandy Mk III 120 watts CAD 1,495 CAD 12.46
Qinpu A-1.0X 100 watts CAD 799 CAD 7.99

Granted, this is by no means scientific but at least it's some kind of quantitative guideline. (And isn't that exactly how we decide what Gigabyte hard-drive to buy?) Here you go, more bang for your bucks! That's what the Chinese are good at. Needless to say, the bang alone cannot justify the bucks. Wattage does not make an amp. (That's what the Brits have been trying to tell the Americans since the dawn of audio civilization.) So let's see how well each of these $7.99 watts translates into music. And that takes us into the second part of this survey - qualitative research.

Long live Class A/B
Without exception, all the British-made integrated amps we've just listed above are good old-fashioned Class A/B designs. The reason is simple: old-fashioned goodness can stand the test of time. There are still a lot of people skeptical about digital amps who can't afford pure Class A. I won't call these people old-fashioned because music listening is an acquired taste. Some ears are tuned to LPs just the same way as some are tuned to Class A/B circuitry. Compared to the designer look of Qinpu's A-8000 Mk II (inspired by the Italian Pathos Acoustics and Unison Research), the A-1.0X is somewhat Spartan if not commonplace. Adorning the black anodized aluminium front panel are a power on/off push-button with coordinating blue LED indicator on the left and four knobs on the right for input select, bass control (+/–10 dB at 100Hz), treble control (+/– 6 dB at 10kHz) and volume control, plus a tiny 'direct' push-button to bypass the tone control circuit. All the buttons and knobs are in glossy chrome finish to contrast the matte black setting. One serious complaint from me would be the lack of a balance control (or dual-mono level controls) which I find useful not only for some classical recordings but also for adapting to room acoustics of less than dedicated listening environments in this component price sector. On the back, there's no tape loop but a pair of pre-outs for connecting to a power amp or subwoofer. No, there's no main-in so it can't be used as a power amp .There are your standard line level inputs for four different sources, an IEC mains inlet and the speaker binding posts. Everything is straightforward without much aesthetic appeal. Likewise for the two-button plastic remote control, which functions really well though when scaling the sound level up and down with precision, sensitivity and zero lag.

Peeping inside, we notice the typical decades-old British integrated amp layout, with heat sink separating the transformer on one side and the printed circuit board on the other. The transformer is concealed by another layer of vented sheet metal. It is a Chinese-made Jia Wei toroidal type rated at 334VA. Leading out from the transformer, two capacitors rated at 10,000 microfarad each join in as power filtration and storage capacity. It is not overwhelmingly impressive since we've seen some 60-watt integrated amps with 40,000 uF capacity - the Densen B110 for example. Input selection is handled by a micro-processor - it's a pity that the same function is not transposed to the remote control. The volume control is a motorized Alps coupled to a Philips low-noise op-amp. Bass and treble attenuations are done through generic pots and op-amps. The preamp section too relies on op-amps, not surprising at all for an integrated amp in this price bracket. The Class A/B circuit involves Hitachi driver transistors and Toshiba output transistors, the latter being the complementary duo of 2SA1943 and 2SC5200 popular among DIYers. It then finishes off with an NEC output protector IC for detecting and preventing excessive DC offset from damaging the speakers as well as providing soft start and soft cut-off to avoid transients during power up or down. Qinpu also claims that an innovative circuitry has been implemented, featuring "single-ended push-pull circuitry with high linearity, effectively eliminating 2nd order harmonic distortion." Also, a 22% negative feedback loop is administered for distortion control and noise suppression. According to the official specs, output power of the Qinpu A-1.0X is 100/160 watts into 8/4 ohms at 0.2% THD with a 93dB S/N ratio. Frequency response is on par with most competitors at 20Hz to 20kHz +/- 0.5dB.

Tools and methodology
In order to discipline this qualitative part of my research, here's the methodology applied. The Qinpu A-1.0X would be inserted into three of my reference systems for A/B comparisons. Bernard Li of Charisma Audio has been extremely kind and patient to let me keep the loaner for four months to conduct this thorough research.

System A
Source: Restek Radiant CD player, Assemblage D2D-1.0/DAC-3.1 Platinum
Amp: Symphonic Line RG 3 Mk III preamp, Symphonic Line RG4 Mk III monoblock power amps
Speakers: Apogee Centaur Minor, Klipsch Synergy F2

System B
Source: Restek Radiant CD player
Amp: Restek Vector preamp, simaudio Celeste W-4070 SE power amp
Speakers: Mark & Daniel Maximus-Monitor with Omni-Harmonizer

System C
Source: Micromega Microdrive, Deltec PDM Two DAC
Amp: Micromega Variodac as preamp, NuForce Reference 9
Speakers: Mark & Daniel Maximus-Ruby

For the reference gear, I kept all my usual reference cables intact. On the Qinpu I used Unity Audio products, which I found very compatible in terms of pricing and performance. One exception was in System C where I had to use the existing OCOS cables that ran 10' to the left speaker and 22' to the right speaker. That's the only way to keep the gear tucked away neatly in the corner to get my wife's approval. By the way, OCOS (Optimal Connection System) speaker cables require impedance stabilizers attached to the speakers. OCOS claims that their performance is unaffected by difference in cable lengths.