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Reviewer: Srajan Ebaen
Financial Interests: click here
Source: 27" iMac with 3.4GHz quad-core Intel Core i7, 16GB 1.333MHz RAM, 2TB hard disc, 256GB SSD drive, ADM Radeon HD 6970M with 2GB of GDDR5 memory, PureMusic 1.82 in hybrid memory play with pre-allocated RAM and AIFF files up to 24/192; April Music Eximus DP1
Preamp/Integrated: ModWright LS-100 with Synergy Hifi tubes, Esoteric C-03, Bent Audio Tap-X
Amplifier: Trafomatic Audio Kaivalya, Octave MRE-130, ModWright KWA-100SE
Speakers: Audiomanufacture Boenicke B10
Cables: Complete loom of Zu Audio Event, Entreq USB cables
Stands: 2 x ASI HeartSong 3-tier, 2 x ASI HeartSong amp stand
Powerline conditioning: 1 x GigaWatt PF2, 1 x Furutech RTP-6
Sundry accessories: Extensive use of Acoustic System Resonators, noise filters and phase inverters
Room size: 5m x 11.5m W x D, 2.6m ceiling with exposed wooden cross beams every 60cm, plaster over brick walls, suspended wood floor with Tatami-type throw rugs. The listening space opens into the second storey via a staircase and the kitchen/dining room are behind the main listening chair. The latter is thus positioned in the middle of this open floor plan without the usual nearby back wall.
Review component retail: $6.100/pr
Insert favorite verbal spice. Not another §*#! KT88 push/pull amp. Indeed not. John Lam's VM60—for 60-watt mono—is fully balanced. This involves a proprietary balanced-mode output transformer*1 with nested and global NFB loops equally balanced; floating outputs; and the usually associated promise of superior noise cancellation.


I could not use the VM60s via their RCA inputs even when leashed to a passive. Whether I floated their grounds or those of various preamps and variable sources, the resultant noise would have been audible across a transatlantic phone line. The XLR inputs proved dead quiet however so that's what I used.


My job-related very frequent gear swapping very rarely encounters ground loops and then not the sort that couldn't be solved. I'm thus uncertain how to interpret this behavior.
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*1 The OPT's primary is configured in ultra-linear mode, the center-tapped secondary is fully balanced. For RCA input signal the differential input stage acts as automatic phase splitter.
"In fact the VM60 sounds much better in balanced than unbalanced mode" acknowledged the Hong Kong designer and owner of JE Audio who found their noisy behavior in the latter troubling enough to request the loaner pair back for an inspection*2 (which I declined as the very effective packing had delivered the amps in perfect condition). Of course the benefits of fully balanced circuitry are far from universally acknowledged for home hifi.


"Twice of everything for nothing but higher expense and complexity" is how some detractors might sum up their counter position. But this isn't the time or place to question the concept's validity. It's also academic to wonder what these amplifiers would sound like were they conventionally configured. As it is for BAT, balanced operation and JE Audio are joined at the hip.
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*2 John subsequently confirmed that the returned loaners checked out flawless on his bench. This creates great frustration for any manufacturer. The gear measures as it should, the reported issue won't replicate. Dealer and owner feedback for these amps to date include no other noise reports in single-ended mode. Mine thus appears to have been an isolated 'freak' incident.

We've previously featured three reviews on this company. Interested readers might like to reference our archives.

The VM60 innards show off a C-core filter choke, German Mundorf and French MKP coupling and British BHC storage capacitors. The US-sourced M6 silicon steel-core OPT and equivalent Japanese Z11 output transformer hide above deck in their soft-cornered housings. 8/4-ohm speaker tabs with ground connections for each—that balanced thing again—sit right behind the OPT facing upward. Auto biasing means carefree plug 'n' play. Even so the company recommends to leave the placement of the original tube set as delivered. Yes, JE Audio does ship their amps with all valves installed already. An oversized and thus hard to remove foam sleeve inside each tube cage protects the bulbs. Clear instructions to first extract said foam before firing up the amps protects impatient owners against smoke signals. Though completely functional, the black-painted perforated metal cages on four alignment shafts look better off.


The input stage consists of two Sovtek 12X7/ECC83 dual triodes which provide the first voltage gain and receive both the local and global feedback loops. The direct-coupled second stage with its single Genalex 6DJ8/ECC88 adds further voltage gain, then drives the quad of Russian Genalex KT88s. Hard figures for feedback amounts aren't available.

For specs we get < 0.1/1% THD at 10/60 watts respectively, 1V input sensitivity, 47/94K input impedance on RCA/XLR, >85dB S/N ratio, 180 watts of power consumption, dimensions of 325 x 395 x 120mm WxDxH and weight of 25.5kg.

The 60-second power-up cycle is accompanied by the power LED flashing red. A relay click and switch to steady blue signal operational fitness. These amplifiers are non-inverting.
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