FX Audio 502e-l amp modifications

Hi all.

Just purchased an fx audio 502e-l class d amp for the grand total of 19.99 including shipping from ebay in the u.k

Pairing it with an fx audio tube 03 pre amp. For a budget build :).

Just wondered if anyone had bothered to modify one before. Noticed from looking at pics of the board it has a surface mount ne5332 op amp on there which could be swapped out easily enough and potentially upgradeable capacitors.


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19.99 GBP could get you one of those "Wuzhi Audio" style TPA3116 amps. Cheap as dirt, and best of all, 90% of the time it's using genuine TPA chips.
For the unfortunate 10% however, you will be greeted by these CSR chips.
Many sellers would claim them to be Chinese made "3116 substitutes" or "domestic chips"...
I'm curious about how they sound though.
Thanks bud.

I went for a the fx audio 502s pro for 35 pound earlier today. I already have a 24v power supply I can use with it.

Found a thread on here before discussing it and upgrading it. It has socketed ne5322 op amps.

It should hopefully be enough for the bedroom.
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fx audio 502s pro
For 35 pound you have a nice little amp. It can sound very nice. I liked it very much.

After modding it gave a tube like sound, but then the positive aspects... Very nice highs, first impression was, "it sounds dark", but its not.
Pitch black, then the tick of the top of the stick on the plate, that starts to treble and give a very beautiful colorful sound, then pitch black again. Most beautiful cymbals I have heard so far. But due to many film caps soldered at almost every cap.
Re: desoldering caps on these fx audio boards.

I've had no luck so far trying to get a cap to desolder on the fx audio tube 03 board.

Ive got wima caps to replace the stock ones on it. It's lead free solder on the board. I'm trying to use a de soldering pump and it's not having it.

Probably try feeding some lead solder into the joints and then use the pump!.