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TPA3255,TPA3251 with Post Filter Feedback(PFFB)


Joined 2003
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Limited electronics experience and I would really appreciate some guidance. If I were to add a potentiometer in front of the 3E BTL (2 channel boards) What value of the potentiometer would I choose? I can see that the unbalanced input of the board is 10K Ohms. The pre-out going into the amplifier boards is 2v, 200 Ohms?
Thank You in advance!
the better case is your source(DAC) has volume control,
otherwise you may refer this one, typically 10Kohm,50Kohm or 100Kohm POT can be used(the lower resistor the lower noise)
please note, if you are talking about the not-PFFB AMP,you don't need modify, but if PFFB-AMP, then you need modify(see user manual)

Building a couple of multi-channel amps for multi-zone usage. The DAC in front does have VC. But, for multi-zone usage individual controls are desirable. Most of the 3E boards (4 total) are not-PFFB (B version I believe). But, I was planning on ordering one of the new PFFB units as well. I see that I will have to modify this board for single ended input. Thank you for pointing this out to me! If 10Kohm potentiometer will do the job I'll look for a volume taper version from ALPS as this seems to be a popular choice. Thank you for the response!
Here is the link to the 3e-Audio page on AliExpress:

There are four different variations that are listed as "Color" options:
480-1-29A = TPA3255 Mono with heat spreader plate
480-1-29A-NHS = TPA3255 Mono without heat spreader plate
260-2-29A = TPA3255 Stereo with heat spreader plate
260-2-29A-NHS = TPA3255 Stereo without heat spreader plate
Click on one of the four small thumbnail images to choose one of these options and see available quantities.

Currently only the Mono variation with heat spreader plate is available (I see QTY 8 available now). The other boards are probably still being produced (or so I assume). Manufacturing in China has experienced delays due to the COVID surge that happened about a month or two ago, so keep that in mind regarding estimates of when parts will be available for purchase.
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