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I bought 5 SX-1000's for my system about 5 years ago and was very pleased after letting some Aragon amps go on Audiogon, Back then I dealt directly with EJ. Thats not the case anymore...a much larger operation now than it was back then. W4S has had justified success with their products, the SX-1000 included.
I have constantly upgraded my system over the years and after changing out almost all other components the synergy was no longer there. As my system became more revealing I felt the amps no longer provided the sound characteristics I wanted. As stated earlier in this thread, the bass was solid but mids were not sweet enough for my ears and the high end sounded too sharp. This was worsened when turning the volume up high.
I have compared the M-amp which my son purchased before replacing it with the Mc 452. The 452 was just a different level but also a totally different price class. While the SX-1000's are an excellent value at the price they lose in a direct comparison with the 452.
I made a decision to leave Class D amps for Ayre. I know the price differential is even greater but you asked for comparisons with other amps. The W4S amps are not even close to my current Ayre's, except, perhaps, in the bass regions. But the "Twenty " upgrades on the Ayres (mono blocks and stereo) closed that gap to where I no longer miss the W4S on the bass either. Imaging, soundstage, musicality, detail and "balance" are all way better on the Ayre's. And i can now crank my system without the sound grating on my ears. At lower volumes the SX-1000's were "OK" but it was frustrating not to be able to listen comfortably at higher
I know W4S has a replacement planned (The Statement) which I attempted to "beta test" back in December but was told it wasn't ready but would be by the end of January. Still no new amp as of early April. So I tried to stay in the W4S family but it didn't work out. I liked the design with the transformer which has is a similar concept to the Theta Prometheus. Time will tell how good the The Statement will be. My guess is that it will be a nice step up from the SX's.
Wyred is a great company and EJ a very young and talented engineer. But the position they have staked out in the business is as a value brand and that usually has some limits.
If you are using a system primarily for HT I think the SX's can be quite satisfactory. Critically listening to music on the SX's vs a good Class A/B design demonstrates the delta between the designs. Perhaps over time the gap will be closed but keep in mind that even the more wacky priced Class D amps from Mola Mola to D'Agostino have been reported to not always have the musicality some desire. On the other hand there appear to be many satisfied owners too.
The point is that this hobby is personal and each of us hears with out own ears and have to reach our own decisions about what works best for each of us. So my advice is to ignore the responses in this thread and demo the amps in your system, in your room with the music you like to listen to. Only then will you truly have your answer.
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