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Reviewer: Glen Wagenknecht
Financial Interests: click here
Sources: Luxman Brid CD Player modified by Audio Upgrades to be a now tube-less, zero oversampling machine with integral volume control
Audio Space CDP 8A CD Player
Preamplifier: Audio Space Reference 2S
Amplifier:Bel Canto 200.4
Speakers: Apogee Duetta Signature, Paradigm Servo 15 subwoofer
Cables: Signal Cable Silver Reference interconnects and speaker cables, Audio Art SE cable loom
Resonance Control: Solid Tech, EquaRack Footers, Weizhi Precision Gold Glory footers, Boston Audio TuneBlock2 footers, Superspikes, and Black Diamond
Powerline conditioning: Noise Destroyer power filtration
Room size: 12' x 17'
Review Component Retail: No.23Mk2 preamp $3999; No.88.6 power amps $3999/pr; TrueHarmonix Black Magic CD mat $69


TrueHarmonix is a fresh new face on the North American scene. This Hong Kong based company has decided to introduce two tiers of tube-based products, one under the TrueHarmonix banner aimed at the mid-priced end of the market, the other as the Sound Master line which is further upscale and includes two reference products which represent designer Peter Lam’s assault on the state of the art. Manufacturing facilities are located in Hong Kong but parts sourcing is international and extends to Taiwan, Canada and the US. Tubes are selected from a combination of NOS and the highly regarded Full Music/TJ lineup.


The basic level of the Sound Master line consists of a single-box linestage preamplifier, the No. 9, and a KT66-based stereo amplifier, the No.34.2. The Reference series reviewed here consists of a linestage and monaural amplifier. The No. 23 Mk II Reference line stage is an ambitious two-box affair with an exotic choice of tubes. The unit is switchable between 300B and 2A3 and also accepts the PX4 for a variety of system voicing options. The second component is the No. 88.6 Reference Mono Block running four KT88s per channel.


The Sound Master No.23 Mk II Reference linestage is not a mainstream product. Unlike most preamplifiers which cater to a broad spectrum of audiophiles, the No.23 Mk II is aimed at a very specific audience - those who run higher-efficiency loudspeakers. This prerequisite has led designer Peter Lam down a different path. The term (pre)amplifier here is actually inaccurate. This is a tube-based attenuator reaching maximum output close to the line level of the source device. Basically the No.23 has less output than a passive linestage and to work to full potential demands a system of considerable efficiency and sufficient gain in the source and amp. The rationale is simple. A regular preamplifier under these circumstances produces too much gain, penalizing the range of available volume adjustments and compromising performance with noise. Here less is more and Peter Lam has given the high-efficiency crowd a dedicated device with potentially superior capabilities.


Unfortunately this does have consequences for those outside the target group. In my setup the Sound Master was operating a good 5 to 10dB beyond its comfort zone and this review can be regarded as a worst case scenario. Luckily my system maintains good dynamic and frequency integrity at lower listening levels so I was still able to get a good picture of the performance potential of the line stage.


The Sound Master No.88.6 Reference Mono Block power amplifiers are heavyweight efforts boasting 4 Chinese-sourced KT88s supported by a trio of cryo-treated 6N8Ps. The amplifiers are switchable from 100 watts UL to 60 watts triode mode. While this power situation may seem deficient in light of my Apogee speakers, people familiar with the capabilities of the KT88 tube will know that it can flex a fair bit of muscle and doesn’t mind a challenge.

The company was kind enough to include their TrueHarmonix Black Magic CD mat for evaluation as well. This accessory is designed to enhance the ability of the optical data retrieval system in a CD player to more accurately read the disc information. Since the CD medium is an optical/mechanical system, it can be easily compromised by small and diverse errors. I routinely make use of resonance control devices because they have proven to be beneficial against vibration-induced errors. But these only address part of the issue and errors in the light path can further impinge the ability of the laser to accurately read the CD. A properly designed device like this may be small in weight but has the potential to be relatively significant in performance.


Four good-sized cardboard boxes arrived totaling some 140 lbs. The preamplifier came in two separate boxes, one for the main unit and one for the power supply. Each of the mono amps came in its own packaging. All components were double boxes and surrounded by slabs of individually cut ply foam, 1 inch thick for the preamp, 1.125 inch for the amplifiers. Vacuum tubes were individually boxed and tubes sets were heavily bubble wrapped and bound in tape. Despite these precautions, a tube selector switch on the top of the preamp had snapped off in transit. Although not included in the review samples, the product would normally ship with manuals and their own house-brand Power 1 cords. Since the cables were not on hand for comparison, I cannot comment on their capabilities. Regardless, the purchaser is always free to experiment with different aftermarket power cords. The designer has chosen a purist approach with regard to convenience features and therefore no tone controls or remote are provided for the preamplifier.

The Sound Master No.23 Mk II Reference Preamplifier is the second line stage to grace my listening room which uses tubes normally seen in power amplification. My Audio Space Reference 2S-which also has provision to switch between 300B or 2A3 tubes-is currently running with the 300 B. The Sound Master was delivered with a third choice of exotic tube, the PX4/n. By reputation, all these tubes are rivals for exquisite midrange reproduction and all are also known for a predisposition towards microphonics.


The No.88.6 Reference monos are the second tube power amp utilizing KT88s  to do service here, the previous unit being the Tim de Paravicini designed Michaelson & Austin TVA 1. My history with the abilities of the latter amplifier allowed me an interesting opportunity to examine the evolution of the species. The preamplifier is a two box affair with section sporting large transformers. As delivered, the 16.6 lb main unit uses two PX4/ns driven by a pair of 6SL7GTs. The outboard power supply is 21.4 lbs and uses a Russian 5U4G rectifier, a Sylvania 6L6GA and a Tronal 6SL7GT. The two units are connected via a thick umbilical terminated with multi-pin threaded and locking connectors. The top of the main unit has a small locking toggle to choose between 300B or 2A3 tube operation as well as a secondary volume pot to optimize the operating range of the front-mounted master potentiometer. The rear panel of the main unit has two RCA inputs and a single balanced XLR input. Outputs are a choice of unbalanced RCA and balanced XLRs. The custom proprietary RCA connectors are solid-fitting gold on copper.


Basic construction is sturdy folded sheet metal with heavy gauge face plates. The preamplifier base plates are composed of massive and heavy steel slabs with four large rubber feet bolted on. Cosmetics of the preamp make generous use of chrome on the top and sides and the huge transformer covers are finished in piano black. The front panel is thick-gauge charcoal black aluminum with a gold-hued fascia displaying the Sound Master logo. The two large front-mounted control knobs for volume and source selection are gold finished and the secondary top mounted volume control matches. Both pots were silky-smooth conductive plastic affairs and operationally silent with a fine range of adjustments. Switch selection was solid and positive.


Internally the preamplifier sheds cosmetic niceties and becomes more utilitarian. Getting down to business is all point-to-point OFC copper or silver wiring with some exotic components such as Jensen copper foil caps. The No.88.6 monos are relatively narrow but quite deep and weigh in at over 39 lbs each. A good portion of the unit is taken up by hefty power transformers neatly hidden away behind an attractive fascia of beveled chrome with a black cap. The rest of the unit is further chromed save for a black base plate and the charcoal faceplate which, like the preamplifier, is adorned with thin gold-colored fascia and the Sound Master logo.


There is a switch labeled "soft/powerful" mounted on the top plate to select between Ultralinear or Triode operation. The rear panel has single-ended RCA and balanced XLR inputs with a small selector switch. Output connectors are heavy-duty plastic-shrouded gold-plated copper binding posts with a center hole to accommodate bananas. In practice I found these holes to be a little oversized, making for a less positive connection with my expandable locking connectors but otherwise solid and able to accept very thick spade connectors. There is a slight delay on power up as a muting relay allows the circuit to stabilize. Four large rubber feet are bolted onto the amplifier base plate which utilizes more traditional vented sheet metal. Internally there is a combination of point-to-point wiring and circuit board with premium parts.

The TrueHarmonix Black Magic CD mat came in a form-fitting plastic case. The mat is a lightweight black floppy disc whose ‘magic’ ingredient is a proprietary graphite fiber composition. It is quite thin and barring an unusually shallow tray, should fit any CD transport.


The Sound Master No.23 Mk II was first run into the Bel Canto 200.4 amplifier both in single ended and balanced configurations. The Luxman and Audio Space CDP 8A digital decks were used as sources, with the Audio Space CD player running single-ended and balanced outputs.


The No.88.6 monos replaced the Bel Canto and also were run both single-ended and balanced with the Sound Master preamplifier. Later tests were done pairing the mono amps with the Audio Space Reference 2S preamplifier running the system in single-ended configuration. The system was also assembled in a purist configuration without preamplifier, running the modified Luxman CD player’s variable outputs direct. The subwoofer was disconnected from the system following evaluation of the No.23 MIII preamplifier in single-ended mode.


The Black Magic CD mat was used at various stages in both the Luxman and Audio Space CD players as well as a lightweight portable player to determine the latitude of its effectiveness. I compiled my standard list of reference CDs and added a few new items to keep the listening interesting.
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