This is a review and detailed measurements of the AIYIMA A20 stereo class D amplifier with high-pass filter. It was sent to me by the company and is on black Friday sale for US $157 (normally $195).
The A20 is the most elegant design I have seen from the AIYIMA. Not only is it stylish, it also has quite a bit of weight to it (for its class). The amp has both RCA and XLR balanced inputs which you can easily select with the switch on the right. It took me a bit to figure out that to activate high-pass filter, you push the toggle switch up a notch past "ON." Nice way to save a switch and still get the job done, allowing the design to look balanced.
Back panel shows everything you wanted but perhaps, had not managed to get in this class of amplifier:
OK, maybe not the giant, 10 amp 48 volt power supply.
There is trigger input and of course, its high pass filter which you set with that knob. I like that it has detents and is rather stiff so you don't turn it by accident. You can bypass the volume control by pressing that button for a few seconds. In testing, I did not find a performance difference between using that, or setting the volume to max.
AIYIMA A20 Amplifier Measurements
I started with volume set by pass and high pass filter disabled using XLR input:
Distortion is kept quite low so noise sets the SINAD (more or less). At nearly 94 dB, this is excellent performance:
It is awfully close to our blue range despite the diminutive size and cost. You lose a bit of performance as usual if you use RCA:
Here is actual noise performance which again for the class is excellent:
Despite implementation of PFFB, there is a slight load dependency:
And that general peaking. High pass works as advertised.
Multitone and 19+20 kHz tests show the typical behavior of rising distortion in upper ranges:
Channel separation is better than average (for all amps):
The beefy power supply turbo charges the amplifier, producing a lot of power in such a small package with 4 ohm impedance:
It is able to maintain that close to bottom of hearing range at 40 Hz:
8 Ohm output is of course diminished but still respectable:
As noted, high frequencies are the enemies of this platform:
Amplifier was stable on power on:
It does however potentially have a power on/off pop:
Conclusions
It is amazing how far we have come in this category of amplifier. AIYIMA was one of the earliest adopters producing performance that was hard to imagine at the time. In A20, it has managed to bring more and more refinement as to define a new class here. Yes, there are a few minor misses like flatness of frequency response but generally, you have a very power full amplifier, with low noise and mostly, low distortion. Combine it with good looks and nice functionality such a proper high pass filtering for subwoofer use and you have a winner here.
I am going to recommend the AIYIMA A20 stereo amplifier.
------------
As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The A20 is the most elegant design I have seen from the AIYIMA. Not only is it stylish, it also has quite a bit of weight to it (for its class). The amp has both RCA and XLR balanced inputs which you can easily select with the switch on the right. It took me a bit to figure out that to activate high-pass filter, you push the toggle switch up a notch past "ON." Nice way to save a switch and still get the job done, allowing the design to look balanced.
Back panel shows everything you wanted but perhaps, had not managed to get in this class of amplifier:
OK, maybe not the giant, 10 amp 48 volt power supply.
There is trigger input and of course, its high pass filter which you set with that knob. I like that it has detents and is rather stiff so you don't turn it by accident. You can bypass the volume control by pressing that button for a few seconds. In testing, I did not find a performance difference between using that, or setting the volume to max.AIYIMA A20 Amplifier Measurements
I started with volume set by pass and high pass filter disabled using XLR input:
Distortion is kept quite low so noise sets the SINAD (more or less). At nearly 94 dB, this is excellent performance:
It is awfully close to our blue range despite the diminutive size and cost. You lose a bit of performance as usual if you use RCA:
Here is actual noise performance which again for the class is excellent:
Despite implementation of PFFB, there is a slight load dependency:
And that general peaking. High pass works as advertised.
Multitone and 19+20 kHz tests show the typical behavior of rising distortion in upper ranges:
Channel separation is better than average (for all amps):
The beefy power supply turbo charges the amplifier, producing a lot of power in such a small package with 4 ohm impedance:
It is able to maintain that close to bottom of hearing range at 40 Hz:
8 Ohm output is of course diminished but still respectable:
As noted, high frequencies are the enemies of this platform:
Amplifier was stable on power on:
It does however potentially have a power on/off pop:
Conclusions
It is amazing how far we have come in this category of amplifier. AIYIMA was one of the earliest adopters producing performance that was hard to imagine at the time. In A20, it has managed to bring more and more refinement as to define a new class here. Yes, there are a few minor misses like flatness of frequency response but generally, you have a very power full amplifier, with low noise and mostly, low distortion. Combine it with good looks and nice functionality such a proper high pass filtering for subwoofer use and you have a winner here.
I am going to recommend the AIYIMA A20 stereo amplifier.
------------
As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
