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I upgraded my BT20a Pro with a GaN 48V 5A power supply and 2 SS3602 chips


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Out of musical curiosity I upgraded my BT20a Pro with a Fosi Audio CC Adapter GaN 48V 5A power supply and a pair of Sparkos SS3602 operating chips, purchased directly from the Fosi website.
I was absolutely amazed at the dynamics and sound quality of the BT20a PRO with the small change.
The initial impact with the power supply, providing greater dynamics especially at high volume levels, highlighted its robustness and guaranteed better protection.
A real surprise was listening after installing the Sparkos SS3602 operating chips. It's clear that this upgrade costs more than just the amplifier, but it's worth it. Despite its compact size, the BT20A PRO holds its own against more renowned and larger amplifiers.
Installing the chips was simple. Just follow the instructions provided by Fosi Audio in their videos. However, you must be very careful as at the beginning it may seem that there is some difficulty in removing the serial chips which fit together very well, which is why special pliers with suitable tips become indispensable. Using this tool you just need to act decisively and it becomes really simple.
The result was more transparent sound, greater instrument separation, and musical detail that surpasses that of much, much more expensive amplifiers.
With simple kef Q350 speakers without taking up much space, I created a beautiful professional music corner in a room that had no music with the connection opportunities offered by the BT20a Pro.
Well done Fosi Audio. Great little amp and instructions for modifying it. I can't wait to get the chance to try out the new amps
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with both. everything adds an improvement. the power supply gives a more powerful full-bodied sound. sparkos major harmonics, transparency and definition