TPA3255 - all about DIY, Discussion, Design etc

TNT

Member
Joined 2003
Paid Member
Played :-D

Just reporting back - this no-name TPA3255 (Audipohnics) and Fiio DAC, fed via toslink from a RME Digiface plays bass below 60Hz like a champ. 2 subs with two 8" each. + 6dB at 20 Hz. Airy, stable, kick... very happy even in this quite high quality system. All in all inc 300W smps: < 150€

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Payed :)

Also got a FIIO D03K TAISHAN DAC Coaxial / Toslink 24bit / 192khz to feed the A07 wich in turn is to be hooked up to my RME Digiface - all managed by a CamillaDSP setup. Mains are also run via opto... A little bit of a trail and experiment :)

But thanks anyways.

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Upon completion of the group buy, I will introduce 2 new amplifiers, Gallium Nitride and 3255, with some schematic tricks added to reduce distortion below 0.0006.

My amp
 

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Does anyone have suggestions or insight on PSU that could be sourced in the EU for two 3E amp's (3255 2ch + 3251 4ch)?
The time to ship something right now is ridiculous, a month within EU seems to be the norm right now.
They are all under the power that the Amp can deliver, but I'm guessing it will be enough for me.
Also, I don't have any ground connection in my house, if some are more sensitive towards not being grounded.
If you have any other suggestions just fire away. :)

I have looked at Connex, MeanWell and possibly Hypex.
For the 3255:
MeanWell MEAN WELL SE-600-48 Switching Power Supply SMPS 600W 48V 12,5A - Audiophonics
Connex SMPS500QRV2 Switching Power Supply Module 500W / +/- 40V - Audiophonics
Hypex (though I'm not sure if it would work) HYPEX SMPS400 / 180 Switching Power Supply Module 400W / 2x46V - Audiophonics

For the 3251 (24-30V) two different Connex:
CONNEX SMPS300REh Power supply Module 300W +/-30V - Audiophonics
SMPS300RS Module d'Alimentation a Decoupage 300W / 32V - Audiophonics
 
Hi,

Connex and Meanwell have both a good ripple (check Jlester Measurements)
SMPS300XX / 500XX and MeanWell LRS-XX are great and seem to be a safe value.

If you are based in Europe, checkout here for interesting prices :

Power supplies Archives - Hifime Audio

With the first DrMordor TPA3251 and 55 I used some Connex SMPS300RS, single rail. I also tested the TZT LLC as you could read and performs as well as the Connex when listening (but I did not measure it).
 

opc

Member
Joined 2004
Paid Member
No need to make any change, I just use the Gnd and + rail = 35V for single rail (vs 70V dual rail). theoretically, 300/36 = about 8.5A
I do not know the calculation method and I am wondering if the amperage is not divided in this case ....

Be very careful with this...

I can't speak for these specific supplies, but generally the feedback for the voltage regulation is taken off one or the other supply outputs, but not both. Since you're only loading one rail, the other rail may climb exceedingly high with no load at all, and could easily exceed the rated voltage on the caps. This could be why you're seeing failed supplies.

Example:

As load increases on the positive rail (the one you're using) the controller sees the voltage begin to sag below the set point, and increases the duty cycle to maintain the set point. This is great for the positive rail, but the negative rail must follow, and there's no load on it at all. The higher duty cycle will result in significantly higher output voltage on the negative rail with no load, and this could in turn damage the output caps or rectifier.

Both rails need to be roughly equally loaded in a split-rail SMPS.

There are other ways to make use of a split-rail supply in single rail applications, but this is definitely not the best way.

To double check this specific supply, you could run the amp at near full power and measure the voltage on the negative rail. If it's below the rated voltage on the caps, you may be able to get away with it.

Regards,
Owen
 
Hi,

Connex and Meanwell have both a good ripple (check Jlester Measurements)
SMPS300XX / 500XX and MeanWell LRS-XX are great and seem to be a safe value.

If you are based in Europe, checkout here for interesting prices :

Power supplies Archives - Hifime Audio

With the first DrMordor TPA3251 and 55 I used some Connex SMPS300RS, single rail. I also tested the TZT LLC as you could read and performs as well as the Connex when listening (but I did not measure it).

Thank you!
It seems like they have slightly limited supplies in Europe, depending on which model you look at.
They have many Connex with dual outlet and the base "R" models. But according to some information I found the RS could be better, I don't know.
I got some help through PM yesterday, I will look into it today and try to get a game plan in order. 🙂
I'm not really in a hurry, but 2-3 months to get parts is sort of taking the fun out of this.