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Sound: For those wanting a second different opinion, John Potis' spot-on prior review (actually the first word on today's subject) won't do. At all. That's because I concur almost entirely. The ST-500 is very cannily voiced. It should get the best from the type of speakers its own price tag pegs as the most likely mates. If those are monitors, they usually need help in the bass. If they are floorstanders, they also appreciate help in the bass, this time to firmly control what they tend to lay on a bit thick. That's particularly true with the widespread use of ported alignments. The low output impedance and current drive of the ICEpower boards are justly popular for their grippy damping and good extension to show up as plate amps in many subwoofers. These qualities are tailor made to compensate for and maximize what one can rightfully expect from sub $2,000/pr loudspeakers.

In the midrange and treble, the current speaker trend is for über detail achieved with forward treble, sharpened attacks and an overall lean tonal balance. The ST-500's voicing counterbalances such tendencies most effectively. It must be why the company reports that this is their most popular amplifier. It's easy to love a well-stuffed cuddly teddy bear.

In my extensive amplifier comparisons the ST-500 was considerably warmer and denser than three different Mosfet amps from ModWright, FirstWatt and Nagra; two valve amps (one Yamamoto 300B SET, one Trafomatic EL84 push/pull); one Power Jfet (J2); and two other transistor amps (F5 and Burson PP 160). The amps with the most speed, resolution, illumination and finesse were the low-power F5 and J2 Nelson Pass designs. In the slightly warmer, softer and thicker next tier sat the Mosfet and valve amps. The M2 and KWA-100 were virtual doppelgänger, the Nagra MSA was more dynamic and resolute. Between the first and second camps sat the Burson whose cooler more lit-up demeanour and accurate slamming bass was closest to the F5 but which lacked some of the latter's organic sophistication to seem more mechanical and rigid.


In this mass grouping, the Wyred occupied a distinctive class of one. It was 'more different' than all the others. Utterly confounding popularly held expectations for class D switching amps, I really felt that it belonged to the prototypical powerful EL34 push/push clan - fulsome, very robust down low, utterly non-offensive but ultimately not that finessed and teased out. With speakers, I'd call up vintage Vandersteens prior to their changed direction as augured in by the models 5 and 7. Or a Zu Druid MkIV. To tip my hat at another former 6moons scribe, we have Chip Stern's intuitive image of comfort food. Enter thick meat with boiled potatoes and plenty of gravy accompanied by a fruity red wine.


That's the most fitting descriptor in fact. Comfort sound. It's the polar opposite of charged, caffeine/adrenaline, zippy, bright, hyper detailed, lean and thin. The ST-500 is proof positive. One-size-fits-all predictions for class D sonics are uninformed and hasty. There's as much leeway in voicing switching amps as there is with more traditional topologies. There's even a precedent 6moons readers should be well familiar with. I'm thinking of Vinnie Rossi's Red Wine Audio battery-power Tripath designs. While I no longer had a—pre LFP-V of course—Signature 30.2 on hand to conduct a direct A/B, I'm very familiar with the RWA house sound. I feel confident in the general overlap of density, warmth and dynamic displacement. The latter is less a function of greased reflexes than impact. Think happy neighborhood slugger.


Much affordable hifi falls on its face by lacking the fleshy materialism of the more expensive better stuff to instead come across as more ghostlike and agitated. Starting out with a mega-pixel fixation on detail magnification, one usually ends up with something quite unsatisfactory over the long haul. In the endless high wire act between resolving power and meatiness, it's far better to err on the side of density particularly in the transitional realm of value-priced components. Extreme resolution without body is useless. Wyred4Sound's ICEpower implementation conforms with that assessment. It tones down illumination, heightened reflexes and raw penetration power. Those attributes would often shine a cruel flashlight on things you'd rather not have highlighted when you frolic in these price ranges.

Instead the designers built out in the other direction - tone mass and a warm voicing that's just slightly opaque compared to speed champs like the F5 for example. To segue back to the top of this page, the only area where I diverge from John Potis' prior assessment is in the overall weighting of his conclusion. I perceive more of a gap to what's possible above. That takes nothing away from the huge value equation by which the Wyred4Sound ST-500 combines tremendous power, bass solidity and drive with long-term-suitable cozy sonics. It simply means that in terms of sophistication, the equally value-priced STP-SE preamp and DAC2 from the same company operate in a higher league.


It's likely why, for the upcoming review of Emerald Physics' bi-amp CS2.3 speakers also built by Cullen Circuit these days, global dealer Walter Liederman elected to dispatch a ModWright KWA-100 for the top and today's Wyred4Sound ST-500 for the bottom. As always, it's about balancing out one's compromises to arrive either mostly in the middle; or deliberately shift the sound into areas one personally fancies the most. If the ST-500 had a business card, it'd say on it handyman - strong, reliable, careful, gentle, very friendly and cheap.
Quality of packing: Good.
Reusability of packing: A few times.
Ease of unpacking/repacking: Easy.
Condition of component received: Flawless.
Website comments: Easy to navigate, complete information.
Human interactions: Very responsive and apparently very keen on customer service.
Pricing: A very fine value in the arena of well-behaved muscle amps which 7.1-channel receiver buyers can afford.
Final comments & suggestions: This amp would seem ideal for those lusting after a 100-watt push-pull EL 34 tube amp but who cannot tolerate its maintenance or performance variability from drifting bias and aging. The ST-500 offers more power and better drive for less money but quite comparable sonics. Speakers already on the very warm and thick side would compound for like-meet-like interactions and should probably be avoided.
Wyred4Sound website
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