This is a review and detailed measurements of the 3e audio 260-2-29A TPA3255 chip based stereo amplifier. It was sent to me by the company as a complete unit even though they only sell the amplifier modules.
View attachment 332196
As you see, it is a generic box which is something you can easily build yourself. I don't know what power supply is in there. Will fill in when I know. Cost is US $109 for the stereo amplifier module.
Back side of the reference design:
View attachment 332210
The differentiation here is implementation of "PFFB" which stands for post-filter feedback design. Without this, the required output filter will interact with speaker load, varying the frequency response of the amplifier. High cost amplifiers from likes of Hypex and Purifi have this but budget amplifiers usually do not. I am told there are other optimizations to extract best performance out of this class D IC.
This testing is for the stereo module.
I was also sent a mono amp which I will test soon. Mono review is out now:
https://www.audiosciencereview.com/forum/index.php?reviews/
3e audio TPA3255 Stereo Amplifier Measurements
As usual we start with our dashboard:
View attachment 332197
Wow, I wasn't expect such good performance! Distortion is below threshold of hearing at nearly -120 dB. Noise performance then sets SINAD to 102 dB which easily lands the amplifier in our "Excellent" bucket:
View attachment 332198
Zooming in:
View attachment 332199
SNR is great for 16 bit content even at 5 watts and approaches state of the art at full power:
View attachment 332200
Frequency response shows the effect of PFFB:
View attachment 332201
Multitone shows that distortion in low to mid-frequencies is great but there is some degradation at upper end of hearing range:
View attachment 332202
This is reflected naturally in our 19+20 kHz test as well:
View attachment 332203
Crosstalk is better than average:
View attachment 332204
There is plenty of power on tap:
View attachment 332205
View attachment 332206
View attachment 332207
Notice the very low noise floor above competing with "big boys" of class D amplification there!
As noted, there is some weakness at higher frequencies:
View attachment 332208
There is no standby switch so I had to fully power cycle the amp to get the on/off noise:
View attachment 332209
Conclusions
I am amazed and pleased to see how much performance is extracted out of the TPA3255 class D amplifier IC here. Clearly a good designer is at work here. Noise and distortion are kept at a minimum while producing lots of power. There is some increased distortion at higher frequencies but that is a small consideration in the context of this class of amplification.
I am happy to recommend the 3e audio TPA 3255 amplification kits and products.
------------
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/