This review page is supported in part by the sponsors whose ad banners are displayed below
The quality of bass coupled with the extraordinary grain-free smoothness through the midrange and treble; plus the amount of retrieved detail made for an exciting, well-articulated presentation that quite often allowed me to forget the mess of boxes and wires littering my living room to instead focus on the music at hand. That happens all too rarely and is usually something I find only with vacuum tubes. Yes, there were tubes in front of the amps via my Manley Labs Shrimp preamp but I found much the same effect running the monos direct with the completely solid-state Shanling PCD3000A CDP.

My similarly priced but decidedly less powerful Manley Labs Mahis were very different sounding. Regardless of choice of speakers, the Mahis' presented music with a more visceral, harmonically richer texture and a more lit-up open top end. Nevertheless, they were nowhere near as powerful or dynamic as the SX-1000s. Nor did music emerge from as quiet a background. Information retrieval was also less impressive. Oddly enough, I found myself preferring the Mahis to the SX-1000s, which to my ears were the more transparent, resolving and ultimately more truthful amps. Perhaps I'm a sucker for a little even-order distortion. However, that says more about my sonic biases than which amp you should buy.

Compared against my recently acquired Audiomat Opéra Référence, the SX-1000s couldn't quite match its degree of vibrancy, truth of timbre, texture and lifelike immediacy. Moreover, those attributes of the French piece don't come at the cost of resolution or noise à la the Mahi. The Audiomat is one of the quietest, most resolving amps I've ever heard, tube, solid-state, class A to Z. There's something else too. The Frenchman engaged me emotionally to a greater extent and had a way with the flow of music that the SX-1000s couldn't quite match. Frankly, little else I have heard regardless of price can. However, the Opéra Référence retails for nearly four times what the W4S monos command so this really wasn't a fair comparison. The point is, spending more does sometimes get you more. Still, match the SX-1000 monos with the right preamp and speakers and you may not feel the itch to part with more cash. In addition, there is the finite life and replacement cost of tubes plus the inevitable speaker matching issues with any 30-watt tube amp.

Later during the review, I dragged the AV123 Strata Minis I reviewed and subsequently purchased last year from our TV room and plunked them into Paul's Sonic Temple. Now here was an excellent and affordable match. The SX-1000 mono took complete control of the Strata's drivers and delivered a performance that had me second-guess my review of these speakers some months ago. The opaqueness in the Strata's top end I had previously noted evaporated. Spatially, everything blossomed so I could hear further into the soundstage. Instrumental and vocal images snapped into greater focus. Bass extension and definition improved. The jump factor and emotional engagement shot way way up.

Matched with the Strata Minis, the SX-1000 monos were awesome. In fact, switching back and forth between my Callistos and the Minis over a couple of weeks, I eventually preferred the monos with the latter. Overall, there was a fuller, richer, more exciting presentation. Maybe it was a synergy thing. Or perhaps the Strata Minis were masking something the Callistos were revealing in the amps’ character? Whatever the reason, for $4,500, this was a bloody impressive match. Want even more value? Try adding Shanling’s $600 PCD3000A with its onboard analog volume control and run the amps direct. You might miss the more fleshed-out presentation that a decent preamp can provide but we’re talking a complete full-range system sans cables for just over $5,000. It baffles me how some folks are crying the Blues over the state of the audio industry these days. There seems to be more decent-sounding affordable product around now than ever before.


In conclusion, the Wyred 4 Sound SX-1000 monos sure sounded different from most amplifiers I am familiar with and it was a snap to differentiate them from my own. However, the manner in which they presented music was similar to other class D amps I have heard. This may be a broad generalization but to my ears where the D class strikes gold is in overall smoothness, neutral tonal balance, low noise and resolution of low-level information. The SX-1000 monos have all that in spades - plus excellent dynamics, transient response and the ability to play loud without compression. Considering what you get for the price, these amps are a terrific value and for me, epitomize what our Realsization Award is about. Definitely one of the most impressive audio bargains around.
Quality of packing: Double boxed with foam inserts. Appears very solid.
Reusability of packing: Appears reusable several times.
Quality of owner's manual: No complaints.
Condition of component received: Flawless.
Completeness of delivery: Perfect.
Website comments: Decent pictures and information.
Warranty: 3 years parts and labor.
Human interactions: Professional, helpful and friendly.
Pricing: Excellent value - a bargain!
Wyred4Sound website
Underwood Hifi website