This is a review and detailed measurements of the SMSL A100 A100 stereo amplifier. It is on kind loan from a member. I can't find it on sale anywhere but seems to have cost US 100.
View attachment 204839
I like the simply but rather elegant/symmetrical design. Same for thoughtful rear connections:
View attachment 204841
Almost every manufacturer puts both speaker outputs together making it so hard to plug in the banana plugs. Here they are spaced apart which essentially solved that problem.
Inclusion of an AC power supply is unheard of in this price class and nicely declutters your desk.
Oddly the USB input is type A. At first I thought this was for external storage but manual talks about using this with a computer. I didn't have a type A to type A cable so didn't test this and stuck with Aux analog input.
The heart of the unit is Infineon MA12070 class D amplifier.
SMSL A100 Measurements
As usual we start with our dashboard:
View attachment 204844
Distortion is actually better than 90 dB but there is rising level of noise and high order spikes which drag it down to 76 dB. This puts is slightly below average:
View attachment 204845
Edit:
Request was made to measure using USB input. I had to use a special breakout box to interface to the unit given its type A connector. Here is the dashboard:
View attachment 205959
As you see, performance is degrade fair bit. My breakout may be causing some clock jitter but then again, if async USB is implemented, this should not be the case.
Noise performance is "OK:"
View attachment 204846
Multitone shows the same problem at high frequencies:
View attachment 204847
I expected frequency response to have load dependency but thankfully, it did not:
View attachment 204848
What ringing it has is above audible band which is good.
Crosstalk is very good, beating some home amplifiers:
View attachment 204849
Power output is naturally modest:
View attachment 204850
View attachment 204851
View attachment 204852
Sensitivity to high frequency input becomes very clear as we do power sweeps:
View attachment 204853
Unit didn't need any warm up.
Conclusions
The message here is a sum of good and not so good. I really like the frequency response for a class D amplifier and inclusion of AC power supply. Distortion on the other hand rises with frequency. I like to see perfection but we don't have such an example below $350 currently. Overall I would say not a bad attempt. Strange that despite having become available late last year, it is discontinued already. Maybe there are part shortages.
I am going to recommend the SMSL A100 as a budget amplifier.
----------
As always, questions, comments, recommendations, etc. are welcome.
Any
donations are much appreciated using
: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/