TPA3255 - all about DIY, Discussion, Design etc

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Doc,
Given my speaker specs above, is it good to go with 36V smps ok?
Won't listening in high volume.
My Aiyima A04 itself, max is 12-o Clock only.
 
By using LT3045 LDOs in a few places and using an oversized inductor I took today the first FFT of our amp at 5W , 8R 15db gain
Please note that this is our first test with no optimization whatsoever. We expect better in a few weeks.
Note the absence of H after the 5( that in itself its very low). Same pattern at 10W
 

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By using LT3045 LDOs in a few places and using an oversized inductor I took today the first FFT of our amp at 5W , 8R 15db gain
Please note that this is our first test with no optimization whatsoever. We expect better in a few weeks.
Note the absence of H after the 5( that in itself its very low). Same pattern at 10W
-100dB H2 is in the same ballpark with my measurements. I do not expect there is much to be improved in this aspect, neither will this be really necessary.
 
-100dB H2 is in the same ballpark with my measurements. I do not expect there is much to be improved in this aspect, neither will this be really necessary.


Hi



H2 is at -106 thats half the distortion compared with 100.
Further reading is on the first power on , we have scope for at least 6db further reduction by tweaking (we run on 450Khz , PSU is dirty SMPS) so I would expect it to be -110 to 112 when we are finished.
Note that at this THD , this amp equal the best class D amps (Hypex etc)
Is THD equal to SQ ? Its a part but not the whole story. For example I think that after h5 you should have no harmonic for great SQ.
At last , there was a review of one of my older designs(volt+d) on audiosciencereview by Amir. One of the important parameters (in my personal opinion) is noise at SW frequency. When measuring Volt+ they found almost same noise on our amp (sw frequency attenuation by 90db compared with fundamental) comparable with class AB.
Is it necessary to get the best numbers out of this board ? I think its very important .Not only THD but everything else (SW noise , N in THD+N , lowest magnetic hysteresis )
 
Thanks Doc & Gasolin!

Doc,
Is it necessary to use Preamp for 3E TPA3255 board?
any drawbacks if I use one?
planning to use RCA & PC USB decoder as input options.

must to have pot in amp, cannot rely on software volume controls

a pre-amp is not needed. works very well from a smartphone or DAP or DAC. However if you want full output, as loud as possible then a preamp of some sort is wanted for output from small sources. a car headunit for example tend to have a stong, higher voltage output so no preamp needed.

I use EQ/crossover anyway, so thats my preamp. else i have used headphone amps to boost signal or the output from usb recording or listening audio interfaces.

if the preamps are a bit noisy, then they add noise. depends on how good the gear is. car audio phoniex gold eq/crossover usings ne3255, adds a little noise but its quite good 🙂. it was top of the range of its time, heck the pcb is gold plated :O.
 
Yo amigos,

New DrMordor TPA325X amps with PFFB. (based on 360 Customs design)
These high ends TPA325X sound awesome. They are shoulder to shoulder with my Hypex Ncore.

- TPA325X chip
- Wurth / Epcos main caps
- Wuth / Ferro inductors
- Elna Silmic II buffer caps
- PFFB enabled
- OPA1602 / NE5532
- SMPS PSU / LLC / Softstart

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I am not quite sure if I have everything beside a suitable case for the project

Source is stoner-audio DAC/Headamp UDXA ( stoneracoustics.com/udxa ) via
XLR Balanced Stereo

two nice XLR neutrik mogami cables
fused iec socket power in
4 banana plug terminals speaker outs
2x Female XLR Sockets as inputs
EAUMT-0260-2-A (have it for about 2 years)
Mean Well LRS-350-48

I am missing anthing obvious beside a case?
since I have no experience I will have to commission the build to someone


thanks for any advice!