Cheap TPA3118D2 boards, modding them and everything that comes with it

Finally you should post your measurements to the vendor thread, not the DIY thread..

Beside this,
the reports are kinda useless for most of us and, there's something really wrong with your setup from the gain aspect.
The f-sweep from 20Hz-20kHz shows a bandwitdh of 500Hz to 12kHz.
All your measurements where taken at lowest possible gain with 100mVrms..
That's a whooping 1Vrms into 4R -> 0.25W.

If you want to show the uber performance of your amp, do plots like shown in the datasheet so it is comparable. Everything else is just "reactive power".

I'm sorry for not being the nice guy regarding this issues.
 
Last edited:
Finally you should post your measurements to the vendor thread, not the DIY thread..

Beside this,
the reports are kinda useless for most of us and, there's something really wrong with your setup from the gain aspect.
The f-sweep from 20Hz-20kHz shows a bandwitdh of 500Hz to 12kHz.
All your measurements where taken at lowest possible gain with 100mVrms..
That's a whooping 1Vrms into 4R -> 0.25W.

If you want to show the uber performance of your amp, do plots like shown in the datasheet so it is comparable. Everything else is just "reactive power".

I'm sorry for not being the nice guy regarding this issues.

I have been asked multiple times to post the measurements on this forum and did so. I am very careful not to advertise or lately even mention the name of our product because I try my best to comply with the rules of this forum.
 
Last edited:
The 2.1Vrms setup is for connection check only.

From the rms-values of this test it can already be seen that there's something wrong with the gain of the tested amplifier.

At 15k with 2.1Vrms input:

attachment.php


With only 100mVrms input gain increases by 3dB..

attachment.php


Power compression? Or weak power supply..

Anyway, no 20dB here.
 

Attachments

  • 15k.png
    15k.png
    16.1 KB · Views: 490
  • 15k2.png
    15k2.png
    26.7 KB · Views: 487
AES17 doesn't affect respons below 20kHz, I meant it can't show any meaningfull THD.

If frequency respons of that ampboard is like the graphs show, I would have expected people posting experiences with the ampboard to write about the total lack of bass and mid.
 
question for doctormord

I am playing around with the tpa3128 ampboard with the se->diff inputstage like 32xx evm's and the more extensive outputzobel (part of postfilter feedback for evm's).

Inputcapacitors are 10uF. Is it to be expected that the simple 3 component antipop as proposed (360customs.de) for standard tpa31xx boards produces a cracking sound when powering on and off with these different value inputcapacitors or different input circuit ?