SDS-400C Class D Audio Stereo Power Amplifier

Here goes my review with a numbers of audio tracks:

蔡琴 - 被遺忘的時光 No noise or anything, it's dead silence sound! Even with my DAC volume at 100%, WOW, no words anymore.

Libera - Ave Maria As most of the class D amplifier slowly take a place in market, a lot of critics on treble harshness, and yes personally I'm facing this problem when driving Wharfedale Diamond 122 with Topping TP60, the treble sibilance make you think that it shouldn't be there, unnatural cymbal sound, and extra hissing that is so annoy. But this Class D Audio power amp made in the USA does not have this problem, the high note sound smooth with no harshness or whatsoever, angelic voice are unleashed beautifully.

Radka Toneff - My Funny Valentine, The Moon Is A Harsh Mistress Although this amp is dead silence, but I must emphasize that noise/hiss in original recording will not be filtered/altered in anyway, as you still hear those hiss in background for these 2 songs, in any case I always stick to transparent setup.

降央卓瑪 - 紅梅贊,
Stan Getz & Joao Gilberto - The Girl From Ipanema,
Queen - Bohemian Rhapsody Vocal and instrumentation separation for this amp is very clean, it does not mess up the sound like some amp that add "warm" layer.

S.E.N.S. - Palace Memories,
Bo Stief Dream Machine - Heart,
Asura - Ascension In Blue,
Asura - Farscape 7 (feat. Ayten) - This is the first time I feel so tremendous and stable sound stage, especially the track Palace Memories, cranking up the volume all the way to max you still feel it sound so effortless, plenty of power from this little amp

Ok, next I'll focus on bass tracks, distortion, slew rate, and damping factor.

Hans Zimmer - Mombasa - Ok, I have to admit there is some less than perfect result for this track when I crazily cranking the gain & volume to max, the woven Kevlar bass cone refuse to give a sound, haha look what I've done, but then if I set back the gain to 0db, while DAC at full volume, it just fine, I have no words about this kind of jaw dropping tight bass with zero distortion!

Infected Mushroom - The Shen here I would like to bring out the words slew rate and damping factor, the sound just so controlled, seriously it's fast, puncy, accurate, natural, tight and most powerful sound I have ever heard!

韓磊 - 最後的倾訴 Before this, I have a paper popping sound for this song bass sound using Topping TP60, here I dun hear that, instead the separation of vocal and background bass is pretty clear and clean

Joe Hisaishi (久石 譲) - Prince Mononoke start track at Budokan concert (time at 11 min 38 sec)
Kitaro - Matsuri (Live from A Story In Concert in America 1999)
TNGHT - Acrylics For the Prince Mononoke start track drum kick from Budokan concert, I have facing a serious distortions problem with other amps, but this still got a little distort only if you set max gain & volume! As for electronic music, you will be amazed how tight and powerful punchy the bass is, simply fabulous!

The price for this amp is very friendly, I'm sure you all will be shocked at how good it is!

Verdict: Unfortunately, to bring in the amp, I learn a lesson of tax, so be wise in your purchasing, nevertheless I'm willing to pay for this amp again if not only for the nice budget price, but also the best sound you simply can't buy with money. I believe with better speakers like my Wharfedale Denton 80th Anniversary, the sound can be more poison hehe... (Posted on 3/30/2015)

I've used many quality amplifiers (solid state, tube, Class-D) over the years with my Magnepans, and I do believe that the SDS-400C (fed by a tube preamplifier in my installation) is the best I've ever heard this system, period. The amplifier is dead quiet, exhibits deep & tight bass, a clear and open midrange, plus smooth and detailed treble. Power headroom into the 4-ohm speaker load is tremendous. Build quality is top-notch (with a 3-yr warranty to match). A very highly recommended product - Thank you Tom! (Posted on 11/11/2014)

I come from the recording studio and post production world and I must say I am truly impressed this amplifier, especially for the price. I use this amp with a Benchmark DAC-1 and a pair of Focal Chorus 706 in a 18x18x10 room.

The transient are very fast, clear (most important aspect forme). The stereo image is very representative of a what a mix sounds like in a proper studio environment. The bass is deep, punchy. The mids are very detailed, thanks to the Focals. The highs are silky smooth. It's really the definition of high fidelity in my book. (Posted on 3/22/2014)

A beautiful sounding amp in every way. Plenty of power for my 89 db efficient speakers. On a well recorded performance the ambience is palpable! I love it. Yet this amp is clean and clear with no harshness. The background is so "black" that instruments and voices appear to "just be
there" with no background hash interfering with resolution. These amps would not be shamed by any amplifiers at any price! I've not heard theother other other ClassD amps (Posted on 3/3/2014)

A beautiful sounding amp in every way. Plenty of power for my 89 db efficient speakers. On a well recorded performance the ambience is palpable! I love it. Yet this amp is clean and clear with no harshness. The background is so "black" that instruments and voices appear to "just be there" with no background hash interfering with resolution. These amps would not be shamed by any amplifiers at any price! I'ge not heard the other ClassD amps (Posted on 3/3/2014)

My eyes were opened by this compact amp. I almost didn't purchase it because of all the negative audiophile hyper. Well, in every way it is sonically amazing. It has a way of making the background so "black" that you hear things you never knew were there. Clear and clean are the words. But not a hint of harshness! The sound is never glaring, but is wonderfully
airy. And it has plenty of power to make my 89 db efficient roarwhen necessary (Posted on 3/3/2014)

My eyes were opened by this compact amp. I almost didn't purchase it because of all the negative audiophile hyper. Well, in every way it is sonically amazing. It has a way of making the background so "black" that you hear things you never knew were there. Clear and clean are the words. But not a hint of harshness! The sound is never glaring, but is wonderfully airy. And it has plenty of power to make my 89 db efficient roarwhen necessary (Posted on 3/3/2014)

This is a great amplifier. I'm using a tubed DAC/preamp combo with 97dB/watt 7Pi speakers and the high end is smooth and extended with very deep controlled bass. The low level detail, frequency response, and bass control surpasses my tricked out HK Citation II. (Posted on 1/5/2014)