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I first came across Chazz-and-all-that-Jazz at Doc Bottlehead's 2003 Vacuum State of the Art Conference in Silverdale. Catering to DIYers and hands-on audio hobbyists rather than hobnobists and HighEnd snobists, Kevin Haskins was right at home with this event's down-home blue jeans crowd. He used his exhibit room to create awareness about the wide range of amps and speakers he now offers under his DIYCable umbrella. Today's Chazz, a very nifty, flexible and affordable valve headphone amplifier, is a joint venture between Kevin, Brian Cherry and Consonance/Opera Audio of China. Brian is the man behind DIYHifiSupply.com and has a big hand in supplying many US vendors with the well-known TJ Mesh Plates. A native Canadian, Brian's wife is of Chinese descent, hence Brian's transplant to the Orient. Kevin described Brian as uniquely qualified for his position as "cultural ambassador" in that he speaks the Chinese language, understands the Chinese culture and loves and appreciates music reproduced by valves. At VSAC, their joint creation caught my single-ended Class A headphone fancy in a big, attention-grabbing way.


At $479/kit and $779/assembled, this solidly handsome little bugger gets drop-shipped from Hong Kong via 4-7 day Airborne Express or FedEx (Brian's still negotiating between either for the best rates). US customers should thus add roughly $125 in freight to find one of these on their doorsteps. The assembled price includes delivery and a choice of output tubes itemized on the DIYCable website. And because -- if you felt so inclined -- we're talking hands-on fun with the soldering gun, Kevin offers the following upgrade options:

  • #1 DACT Attenuator: $151
  • #2 BlackGate polarized cathode bypass, Kiwamie resistors, silver hook-up wire & Jupiter coupling caps: $99
  • #3 As #2 but substitute Audionote Cu PIO $109
  • #4 BlackGate polarized cathode bypass, Kiwamie resistors, CCC Vampire hook-up wire, Auricap coupling caps: $80


As one of those reprehensibly subjective audio journalists, my review loaner was completely stock except for a $20.74 mercy upgrade of Auricaps. Sniff and wobbling self-image. Are you kiddin', bud? Wake up and take a look at strapping ChazzMan. Then tell me why you would want anything changed! (Actually, this was the very first assembled unit to come off the production line. Kevin didn't want to incur time delays of 'upgrading' certain parts. More importantly, the term 'upgrade' is often misleading and in this context really should be changed to 'difference-grade'. We're talking tuning options, after all - they are contingent on system context and listener bias.) So what have we got here? Provisions for 1/4" and AKG K-1000 style 4-pin Canon terminations. Compatibility with 6550s, KT88/100s and EL34s. Top-mounted on-the-fly triode/ultralinear switch (headphone disconnect recommended to avoid switching transient). Attractive grey hammer finish. Engraved solid wood fascia. Tube rectification. IEC power inlet for aftermarket power-cord swap meets. A cool blue miniature power LED ... Kevin & Brian have clearly shopped for just the right features and appearance. Even jaded been-there-done-that reviewers feel that feisty tingling in their scratchy scrotums: Honest value! Lawd, one could potentially enthuse and go to town over this piece, without feeling called upon to justify $3000/m cables with vacuum-sealed 24K-gold and silver conductors no matter how stellar they might sound.

What's more, I'm an unrepentant fan of the K-1000 earspeakers and thus keenly aware of their potential Achilles heel and need to tame their tipped-up HF balance with copasetic ancillaries. I have long since kept my ears to the ground for an amp that could drive the Ks to the requisite volume levels; not emphasize (or better yet, ameliorate) their tonal imbalance; and be relatively affordable.


Seeing ChazzMan in Silverdale thus equated to an instant desire to hear him do his thermo thing on my own AKGs. Compare that combo to my current K-amp, the excellent Unison Research Unico (which works very well indeed but is more money than I'd happily recommend for dedicated headphone use). Roll some tubes. Flip that triode/pentode switch. Tune in and drop the lot.


Lucky for you and me, Kevin remembered my lust-stricken pleas and dispatched a review loaner at his earliest opportunity. Before things get hot and heavy, the most vital stats: Just a skoch over 12" deep, 11.25" wide and 4" tall inclusive of the footers but excluding the 1.25" by which the tall 5Z3P rectifier extends above the transformer cover. Compliments of Kevin's personal pair of HD-600s, I could evaluate two top-notch dynamic 'phones. He also provided a replacement Cardas wiring harness for the Sennheisers and a Cardas tail for the K-1000s.


In a stroke of parallel synchronicity, James Serdechny of Stefan AudioArt had simultaneously contacted me with an offer to treat my 15' reference run of his K replacement cord with a new proprietary treatment he'd developed since I purchased the cable. While I was jacked into this headphone aftermarket scene, I inquired. Was Sir James interested in providing short-term review loaners of another run of K-wire (terminated not with spades like my own but with the 4-pin DIN plug to match the Chazz); and one run of his Equinox HD-600 replacement cable? James was ready to roll. Soon thereafter, I found myself with two different 'phones; three different cords for each if we count their nasty stock wires; four different kinds of output tubes (I'd pull a pair of cryo'd Svetlana KT88s out of my Audiopax monos but would overlook the further rolling options of substituting the 6SN7 driver or experimenting with GZ34/5AR4 rectifiers); and two modes of amplifier operation.


Pig in shit? Reviewer in hog heaven? Shitty reviewer? Reviewer with shit-eating grin? Something like that. Alas, today won't be the definite, full-hog mud wrestling party. Because of my AKG Jones and upcoming vacation, I shall limit my observations to an initial K-1000 getting-to-know-you session. Once I return, I'll follow up with the proper in-depth testing of the various cable/tube options and the equivalent game of musical chairs Sennheiser-style, then provide some commentary on my favorite flavors in either camp and some comparative notes about their respective attributes. I'll then also compare K-drive between Chazz and Unico, both fed from one of the two outputs of the Underwood Hifi-modified Jolida JD-100, my current headphone rig.


But first, some tech talk. Two stages of DC filtering with a diode bridge followed by a tube rectifier into a C-L-C network create a noise-optimized B+ supply. Joined to careful circuit layout and grounding, it allows the use of AC heating for all tubes. Output noise is specified as less than 0.4mv. Like potential transformer hum, it was utterly inaudible on either phone even with the Alps attenuator fully opened. In the absence of signal, point-to-point wired Chazz with his mil spec metal film Solen caps, Rubycon power supply and bypass caps and quoted 5/9wpc RMS power in triode/ultralinear proved completely mute. That held true even for the higher-sensitivity Sennheisers. Most excellent behavior for Chazz who weighs in at 1.26 stone or 17.5 lbs.

Those familiar with the punishing inefficiency of the AKGs will appreciate their hunger for power, something most standard headphone jack simply can't provide. It's why K-owners tend to own dedicated headphone amplifiers, usually strapping their earspeakers to the speaker terminals for high-level signal connection.


In EL34 mode and on albums recorded at low levels, the fully opened attenuator in either triode or ultralinear mode proved just sufficient. Leaving zero headroom to spare suggested a less-than-ideal scenario though certainly one that doubles as preventive maintenance if you were rightfully leery of unduly elevated playback levels. Kevin's EH6550s, on the other hand, had more output but could still approach max-out on a few very quietly recorded albums.

The cryo'd Svetlana KT88s filched from my AUDIOPAX backup stock had marginally less gain than the Electro Harmonix 6550s but were considerably smoother. They removed a layer of haze or grain as well as forwardness which the feistier 6550s produced. Going back to the Valve Art EL34s which Kevin had dispatched confirmed their reduced gain. They also added a degree of warmth to the midrange but, in toto, weren't quite as refined nor as top-to-bottom coherent and linear as the KT88. Those quickly became my distinct preference. Curiously, the lateral soundstage expansion and depth increase of ultra-linear versus triode mode was less pronounced with the kinky tetrodes than with the 6550s.


Perhaps as a function of my Latin lover trying to emerge from underneath the dominant cold-blooded German -- hey, it's mighty cold in wintry Taos these days -- I've been on a Latin music kick of late. One of my favorite discoveries has been a surprising 2-CD set by Soledad Bravo. It combines the albums Pa' cantar and Pa' bailar under the Lo Mejor title. It offers an extremely generous total of 35 tracks that combine Gitano tunes from the South of France, Afro-Peruvian material and many stellar arrangements of Chico Buarque numbers [Fonart 3039732, 1998]. From sparse guitar accompaniment to full-blown brass/piano/percussion grooves with backup chorus, Lo Mejor is carried aloft by fiery female vocals that borrow from Brazilian Sambista as well as Cuban Salsa and Caribbean Carneval passion.


Needless to say, the highly rhythmic and percussive nature of this fare, the heat of its syncopated trumpets, the struck metal clangs and vocal exuberance add up to plenty of intensity. That's true even without the added brightness or edginess that's often endemic to Latin music recordings but thankfully MIA on Soledad Bravo. Listening to earspeakers an inch removed from your head doesn't create the distance-induced softening that sounds traveling into the farfield of regular speaker setups incur. Biting transients remain biting transients just as they would in the extreme nearfield. The 6550s disqualified themselves not even halfway into the first track of the second album. This made me afraid that despite sufficient power, control and admirably background silence, my hunt for the perfect affordable K-amp would have to continue.


Not. The Svetlana KT88s instantly removed that peculiar inner ear ringing/pressure/aggravation which the AKGs can provoke on the wrong material when not catered to. Ahhh. Now we were talking. The lead singer was whispering thick juicy somethings into my ear - well, clearly no 'whispering' here but I was definitely being romanced. Shuttling between ultralinear and triode mode, the extra drive and control of ultralinear gifted me with punchier bass, more three-dimensional stage depth and an extra degree of fullness and gusto. With this type of energetic, bouncy and driven fare, "high-power" was definitely the way to go.

M.A. Recordings' stunning celebration of Robert de Viseé's works for baroque guitar, lute and theorbo, Le maître du Roi/The King's Teacher [Eduardo Egüez, M064A, 2003] instantly telegraphed 'superior recording'. Naturally, this was despite the relative lack of soundstaging data which often gives this away on regular loudspeakers. Regardless, the enhanced perception of space, of sound wafting on air, portions decaying while fresh notes overlaid the fading gossamer strands - all this was powerfully communicated via the AKGs who excel in the spatial dimension. Triode here sounded once again slightly slimmer. Now clearly focused on one solitary instrument's timbre, it was tonally perhaps a bit more accurate but conversely not as full-bodied or dense as ultralinear. On this album, I could have gone either way.


Spinning some Daudé [Neguinha te amo, RealWorld 724359239422, 2003] and Sivuca & Rosinha de Valença [Gravado ao Vivo, RCA/BMG 743218655852] to stay in the Afro-Brazilian groove merely confirmed my overall impression: Outfitted with KT88s from my on-hand tube choices, Chazz on the AKGs was just as promising in "real life" as he had suggested under show conditions - which often are anything but real life (usually far worse but headphones take the whole room mess out of the equation - but there's still the psychological kid-in-a-candystore factor). Needless to say, the Sennheisers are liable to completely change my tube preferences, something the main review will investigate. And let's face it, the Senns are the far more likely candidate to be used on Chazz - they're less esoteric; they're sealed designs; and they don't require the unusual amplifier grunt of the AKGs which are both an acquired taste and incompatible with anything sporting 1/4-inch jacks.


I now found myself wondering what Sophia Electric's rebranded FullMusic 274B rectifier might do, what kind of 6SN7 NOS valve our own Steve Marsh would recommend. When tube rolling lust strikes, you've gotten down to a level of curiosity and intimacy that's indicative of excitement and arousal. And that is definitely a good sign when you're considering a component under sneak preview. This will be a fun assignment, my friends. Stay tuned for the real pig-in-shit adventures, in this smorgasbord of headphone-related choices offered by little ChazzMan who, incidentally, now comes with a black transformer cover just like the Basie on DIYCable's website ...