Grounding TPA 3116 2.1 Amp


I am adding a simple case to my 2.1 amp board+switching power supply board combo, planning to use it for a very simple home studio monitors. Should I ground the two boards?

Previously, I used this amp to just drive bookshelf speakers with a 3.5 line input, had no grounding, and no issues with that.

Now I will be connecting A&H mixing desk to it (two guitars to the desk via regular unbalanced cables).

So I realized that I don't know if I should ground the boards, and, if so, how? Either boards don't even have an obvious or dedicated grounding terminal or spot but I can probably find it on the boards.

But should I? All in me says that I should but why then the boards do not make it easy?

Please advise!


  • PXL_20230604_165257264.jpg
    445.9 KB · Views: 83
  • PXL_20230604_165231498.jpg
    588.6 KB · Views: 89
holy crow...this works without noise?

i get using wood as a case material but that leaves you with no shielding... try bringing a fluorescent lamp or an SCR dimmer near your amp and see if any noises come through your speakers.

might just be me but i would 180 the power supply board so the low voltage terminals are facing the rear of the case that would allow you to shorten the wire run between the boards as well as twist it and i'd shorten the ac lines as well.