I used RMAA to do some basic testing. 

Testing setup : PC sound card -> Amp line in -> Amp speaker out -> 4 ohm load -> Passive Preamp -> mixer preamp -> PC sound card in.

 

Passive preamp is to lower to amp's output voltage to line level, mixer preamp is to convert the balanced signal to non-balanced for sound card input.

 

RMAA test result for 1W, 10W, 100W, and 294W at 4ohm load:

 

 

Click the below links for the detailed test graphs :

- Frequency response

- Dynamic range

- THD

- IMD + Noise

- IMD + N (swept freq)

 

My sound card's loop back THD is about 0.0017%, so the BPA300 THD result here may be limited by the sound card.

 

Listening impression : the sound characteristic of this BPA300 is similar to my other LM3886 and LM3875 gainclone. These mono blocks has deeper sound stage, better stereo imaging, much tighter and better controlled bass. Overall I can say this truly is a high end audio equipment.

 

--> Discuss this BPA300 design at diyaudio.com

 

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