This is a review and detailed measurements of the SMSL VMV A1 Pro GaNFET Class D stereo amplifier (bridgeable into mono). It was sent to me by their distributor, Aoshida audio, and costs US $495.
I like the inclusion of volume control and display (there is also a metal remote). Back panel shows the inclusion of power supply which is very nice:
I wish trigger input was available. Bridge mode requires changing modes in the menu. When I did that, the amplifier would not produce any output and some red LEDs would be blinking through the back terminals. I tried a few things and eventually gave up. Also, and maybe related, the positive speaker terminal for the right channel was loose.
In use, the amplifier ran very cool, much cooler than its competitors. It mildly got warm to touch. Maybe this is one of the benefits of GaNFET transistor technology.
SMSL VMV A1Pro Amplifier Stereo Measurements
As usual, we start with our dashboard of 1 kHz into 4 ohm load:
Distortion and noise are low enough to land the A1Pro in the top of our "competent" category:
Noise performance is very good:
Company frequency response measurements show slight sensitivity to load. I measured more but still less than some other amps without post filter feedback:
IMD distortion is within the expected range:
Crosstalk is not bad either although I expect better numbers in lower frequencies:
At 4 ohm, distortion sets in a bit early but noise performance is very good:
We do fall short of company specs for power:
I was surprised to see a sharp drop in power at 40 Hz:
This is reflected just the same at 20 Hz in our frequency power sweeps:
Amplifier is stable on power up:
And may only have a power off pop:
Conclusions
Performance of the A1Pro is above average in a number of categories but for the price, it should be that way across the board and it is not. To wit, it should not have load dependency, nor the sharp power drop at lower frequencies. As with a number of GaNFET designs I have tested, the marketing value of the technology seems to be higher than reality. Here, the only benefit seems to be lower power consumption. Otherwise, even IC amplifiers outperform the A1Pro. Those products are messier to use though by having large external power supplies.
I was close to recommending the SMSL VMV A1 Pro but at end, I could not. Company should strive to do better to match the excellence of the rest of their product line.
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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/
I like the inclusion of volume control and display (there is also a metal remote). Back panel shows the inclusion of power supply which is very nice:
I wish trigger input was available. Bridge mode requires changing modes in the menu. When I did that, the amplifier would not produce any output and some red LEDs would be blinking through the back terminals. I tried a few things and eventually gave up. Also, and maybe related, the positive speaker terminal for the right channel was loose.
In use, the amplifier ran very cool, much cooler than its competitors. It mildly got warm to touch. Maybe this is one of the benefits of GaNFET transistor technology.
SMSL VMV A1Pro Amplifier Stereo Measurements
As usual, we start with our dashboard of 1 kHz into 4 ohm load:
Distortion and noise are low enough to land the A1Pro in the top of our "competent" category:
Noise performance is very good:
Company frequency response measurements show slight sensitivity to load. I measured more but still less than some other amps without post filter feedback:
IMD distortion is within the expected range:
Crosstalk is not bad either although I expect better numbers in lower frequencies:
At 4 ohm, distortion sets in a bit early but noise performance is very good:
We do fall short of company specs for power:
I was surprised to see a sharp drop in power at 40 Hz:
This is reflected just the same at 20 Hz in our frequency power sweeps:
Amplifier is stable on power up:
And may only have a power off pop:
Conclusions
Performance of the A1Pro is above average in a number of categories but for the price, it should be that way across the board and it is not. To wit, it should not have load dependency, nor the sharp power drop at lower frequencies. As with a number of GaNFET designs I have tested, the marketing value of the technology seems to be higher than reality. Here, the only benefit seems to be lower power consumption. Otherwise, even IC amplifiers outperform the A1Pro. Those products are messier to use though by having large external power supplies.
I was close to recommending the SMSL VMV A1 Pro but at end, I could not. Company should strive to do better to match the excellence of the rest of their product line.
------------
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/