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Back in Toronto, I contacted Bernard Li of Charisma Audio, the Canadian importer of Audio Space and told him about my Hong Kong meeting with Peter. Without further prompting, Bernard agreed. What's the point of writing an interview without a proper review to attach it to? Though I had my preference for which models to audition, I let Bernard deal the cards. A few days later, the Pre-2 and Nova M-34 monoblocks arrived. That was late May 2007. When I unpacked the amps, I had to admit how this was the most thoughtful packaging I'd ever come across. The sealed double boxes with thick foam cradles, sponge-wrapped tubes and adhesive protective film on the transformers as well as the mirror-finished stainless-steel chassis all indicated that the amps were factory fresh. To a reviewer, removing these shipping protections was a tedious chore, especially the sticky film. However, to the actual owner, it would be customer satisfaction guaranteed. There even were red and white rubber dust covers protecting the RCA sockets.

With a footprint of 10" wide x 14" deep and weighing a claimed 14.3lbs, the Pre-2 looks heavier than it actually is. This deception probably derives from the apparently hefty transformer and massive stabilizer bar which adds 2.3kg. (Still, I thought this amp had to be heavier than 20lbs. I got out my digital bathroom scale and confirmed that the preamp weighed 17.6lbs without stabilizer bar and tubes, slightly over 23lbs fully loaded.) The control knobs are set against a mirror-finished stainless steel front panel framed by 115mm thick black brushed aluminum. Power on/off is performed with the chrome-plated rotary knob on the left. When dialed clockwise, the machine kicks into its protection delay circuit with a crisp click and the red MUTE LED lights up. After 35 seconds, stabilization is complete and the blue CD LED lights up. Press the input selector down to switch through TUNER, AUX and PHONO. The latter will light up green rather than blue.

The hefty black aluminum remote control duplicates all these functions with the addition of MUTE and RUMBLE for cutting down infrasonic rumble, which when activated will turn the PHONO LED to red. The volume knob on the right is also remote controllable through a motorized 100K Alps Blue Velvet potentiometer. As a safety device, the volume automatically returns to zero each time the preamp is powered up, even after automatic power failure recovery. Despite whatever input source you've listened to last before power down, the power-up cycle always selects CD, a perhaps miniature nuisance to die-hard vinylistas. The back panel echoes the fascia with its equally thick aluminum frame. Connections include the IEC power inlet, the four sets of RCA inputs, a grounding post and two sets of RCA outputs - one PRE-OUT and one REC-OUT. Personally, I wish they were both PRE-OUTs. Who needs a tape loop these days?

I also find it odd that the ground post is nowhere near the phono sockets. At the bottom, a scheme of ventilation vents with metal screen and aluminum footers with embedded shock-absorbing pellets have now become trademarks of Audio Space. Next to one of the rear footers, there are two tiny holes about half an inch in diameter.

These are the access points for the two dip-switch bays where a flat-head screwdriver can change the PHONO setting to moving coil or moving magnet. RIAA equalization is handled by a high-end glass-fiber IC with self-adaptive impedance to accommodate MC (4 - 680ohm) and MM (47Kohm). Phono input sensitivity is 0.3 - 1mV for MC and 3 - 10mV for MM. Under the bonnet, audiophile-grade components include Audio Space's own proprietary low-heat, low-electromagnetic choke coil, Multicap coupling caps and Elna electrolytic caps. It's interesting to note that for filtering capacity as well as reliability and stability, Audio Space has always preferred their proprietary choke coil to rectifier tubes. Also worth mentioning are Peter's own Audio Space Magic Power power capacitors, which are made with high-grade materials from Germany for high tolerance and 50-year longevity.

The Pre-2 replaces the Pre-1, a long-standing success for Audio Space. Like its predecessor, the Pre-2 is Peter Lau's refined implementation of the Wada Shigeho preamp circuit of the 60s. Wada Shigeho was ahead of his time and dared to challenge the Marantz 7 by improving on its shortcomings. It's inexplicable that the Wada Shigeho preamp isn't more popular in the West. If you Google 'Wada Shigeho preamp', you net no more than five listings. In Chinese, you get 1,870, some of which are DIY Wada Shigeho preamps selling for as little as a few hundred dollars. Without going into technical tedia which I don't understand myself, let's just say that the Wada Shigeho preamp is a modification of the Marantz 7 circuit with the third stage configured to SRPP.

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In essence, the first two stages, VR1 and VR2 (12AX7), continue as voltage amplification but VR3 and VR4 (changed to 12AU7) are connected as cathode follower for the signal buffer. SRPP, the acronym for Shunt Regulated Push-Pull, is renowned for wide bandwidth, negligible phase shift and very low impedance that can drive electrostatic speakers and offers superb rejection of electromagnetic noise. The sonic improvement is most noticeable in the frequency response and S/N ratio. Apart from Wada Shigeho, other designers apparently have left their own marks behind with similar modifications to the Marantz classic including the McIntosh C-22, Audio Research SP-10 and Jadis JP-80 all the way down the line to today's Cayin SC-6LS.

Peter's own realization of the Wada Shigeho recipe dates back to the Line 3.1 preamp of almost ten years ago. That won the 1999 Best Buy Award from Hi-Fi Review, in my view the most authoritative audio magazine in Hong Kong. But the real breakthrough occurred in the Pre-1 when Peter substituted the 12AX7/12AU7 with the 6SN7/6SL7. Being so-called GT (glass) tubes which are physically larger than the MT miniature tubes, the 6SN7/6SL7 have larger screen grids and a greater ability in micro-harmonic reconstruction as well as improved textural body and more potent drive. I also suspect that these octal twin triodes' higher gain benefits the phono stage. However, implementation of GTs in preamps poses more technical challenges in layout topology and resonance/noise control. Peter clearly embraced those challenges and moved from momentum to momentum. (His award-winning Reference 2 fully balanced preamp shown on the previous page features four 300Bs in addition to four 6SL7 and four 12AX7.)

Based on the success of the Pre-1, the Pre-2 ushered in further advances with a completely reconceived layout that realigns the tubes and, instead of remaining hidden underneath, relocates the transformer outside and on top of the chassis for better electromagnetic rejection. Tube implementation is further simplified to unanimously four 6SL7 (stock outfit being Shuguang 6N9P) but I've gleaned from a Chinese review that you can still mix in two 6SN7 for their crisper sound even though the author didn't specify which pair of tube sockets. (I passed the question on to Bernard. As of today, he's still awaiting an answer from Peter.)

To help me with tube rolling, Bernard kindly supplied a dozen JAN-graded Sylvania 6SL7GT and six Valve Electronic CV 1985, which are 6SL7GT said to be of military standard. The general chassis design has followed the Pre-1's low-gravity configuration. The 2300-gram stabilizer bar continues to serve as an effective damping device that minimizes microphonics. The two rotary knobs are now flat-head torpedo shapes, a cosmetic refinement from the mundane, flat cylindrical controls of the Pre-1 - minor details to be sure but they do make a lot of difference to sight and touch.