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Reviewer: Srajan Ebaen
Source: Accustic Arts Drive-1; Audio Aero Prima SE [on loan]
Preamp/Integrated: Bel Canto PRe2; Audiopax Model 5
Amp: AUDIOPAX Model 88; JJAZ IP110KW monos & IP205KW stereo [on review]
Speakers: Avantgarde Duo; Gallo Acoustics Reference 3
Cables: Stealth Audio Varidig S/PDIF, Stealth Audio Indra (x2), Crystal Cable Reference speaker cable and power cords; ZCable Hurricane power cords on both conditioners
Stands: 2 x Grand Prix Audio Monaco four-tier
Powerline conditioning: 2 x Walker Audio Velocitor S
Sundry accessories: GPA Formula Carbon/Kevlar shelf for transport; GPA Apex footers underneath stand and speakers; Walker Audio SST on all connections; Walker Audio Vivid CD cleaner; Furutech RD-2 CD demagnetizer; WorldPower cryo'd Hubbell wall sockets; Musse Audio resonance dampers on DUO subs
Room size: 30' w x 18' d x 10' h [sloping ceiling] in long-wall setup in one half, with open adjoining living room for a total of ca.1000 squ.ft floor plan
Review Component Retail: $5,500/pr for Signature as reviewed; $4,000/pr for standard monos: $2,500 for same-powered stereo version

"Water gives sustenance to life and H2O gives life to music."
Not all ICEpower amps are created equal. This thought accompanied my somewhat shocked reaction when the man in brown dropped of two sizable cartons of considerable weight. Okay, I knew these were silicon amps. Had their designer filled 'em with sand though? Considering that the internal B&O 500A ICEpower modules are a mere 3.5" x 3.5" x 1", what accounted for the surprising 48lbs of each humdinger amp? One look under the lid clarified the heft. The A-Series modules don't include the integral switch-mode power supply of the ASP boards (the whole 500A board is positively puny, here mounted upside-down to the lateral divider and connected via yellow leads to the bindings posts - see below). Henry Ho -- who clearly believes in ultra-stiff regulation, power supply ripple suppression and plenty of capacitive on-demand energy storage -- thus went all the way to Milwaukee to add his own monster supply. It renders his above company motto somewhat of a euphemism. Think 2H2O instead. That's dideuterium oxide or heavy water (its nucleus contains an additional neutron over H2O's lonely proton). Did I mention that Henry's reference speakers are Apogee Scintillas? We're talking power supply erections of Herculean proportions.


The H2O M250 monoblock -- 250/500w into 8/4Ω, 15" x 15.5" x 6.5" WxDxH -- certainly won't ever find itself the butt of lame Viagra jokes. Stout and stiff are the words du jour, all 190,000uf of capacitance worth especially in the face of an analog modulator amp that draws less than 10 watts at idle. As the designer points out, his power supply would be more than sufficient for pure Class A operation in a conventional design. Even the oops-proof packaging and case work -- plain and clean -- go the extra mile, with nothing less than the top plate a full 1/4" solid metal. Silver face plates are available but my review loaners were Henry Ford black all the way. Switchable XLR and RCA inputs, twin pairs of Cardas five-way binding posts for biwiring, the power mains rocker and IEC make up the business end.

These H2O amps thus represent somewhat of a conundrum for those who remember the early days when so-called switch-mode amps were fit only for subwoofer applications. The M250 monos combine modulator circuitry with a traditional analog power supply of extreme reserves and sophisticated rectification. They deliberately avoid the stock switch-mode power supplies of the ready-for-consumption pre-packaged ICEpower ASP Series.

Engineers will tell you that power supplies in amplifiers determine easily 80% of their sound. Hence dearer and statement units tend to go the extra mile in that department. In general, more extravagant power supplies remain unperturbed by high-volume bass-current demands and other instantaneous peak-current challenges. Arguably more important yet on a day-to-day basis, they tend to also add body, weight and often warmth at regular and even subdued listening levels. This benefits the listening experience not just in extreme instances of colossal musical mayhem or movie soundtrack excesses but with any material at any volume. Unlike overkill for its own sake, that's clearly worth paying for.

To boot, these amps are shockingly quiet, evading the usual ticket my 103dB horns write out for producing audible hum, hiss or ocean surf. Power supply ripple isn't simply low but essentially absent, period. These amps are also mechanically comatose -- alive but barely so -- which is a credit to their high-quality toroidal power transformer. It's audibly active only with the ear directly on the chassis and then just so. Add instantaneous action upon power-on (the little delay transformer that insures that in-rush current doesn't trip even your 20-amp circuit breaker gets rapidly out of the way) and no discernable heat buildup even after 100 hours of non-stop operation. What we have here then is an amp as unfussy in operation as it looks. While plain is as plain does -- a variation on Gilderoy Lockhardt's silly Harry Potter quote about fame and fortune -- we naturally expect more in the sonic fields of glory. Once I had ascertained the M250s' operational noise floor into my hornspeakers, I used my Gallo Reference 3s exclusively to report on the amps' interactions with real-world 88dB loads sans active subwoofer modules.
As I've done before with three preamplifiers under review, today's writeup will now converge with my review of the JJAZ ICEpower monos and stereo amp, to report on similarities and differences between them and make hay out of my opening remark: "Not all ICEpower amps are created equal". Here's what I learned about equality and being first amongst equals. But first, one paragraph on H2O Audio's designer. He's an electrical engineer and has designed and built traditional Class A amps for years, alway using his Scintillas as a yardstick for imperturbable load behavior. When the ICEpower modules appeared, he ordered some trial boards and was shocked to learn that, when implemented with his type of "Class A" power supplies, they offered very real advances over traditional topologies in the areas of speed, current delivery into low impedances and immediacy or directness of sound. Especially for high-power applications, Henry doesn't believe switch-mode power supplies are the ultimate solution. He's also learned that the ICEpower modules are exceptionally responsive to rectification, allowing a wide
range of sonic tuning options based on what decisions are made for the power supply. As far as Henry is concerned, his new recipe -- of combining an analog modulator board with a traditional overbuilt power supply -- outperforms his previous Class A designs. He's considering to eventually experiment with the ASP boards to modify their switch-mode power supplies just to expand his insight into this particular Class D approach and discover what happens if one builds the same kind of headroom and apparent overkill energy storage into them as has been done here. But at heart, Henry's clearly an analog man. He doesn't believe there's such a thing as a power supply that's too large.