TPA3255 - all about DIY, Discussion, Design etc

[PSA78]

Two newbie questions if you don't mind.
My 3E boards seem to be delivered with SE, I'm guessing it should be switched over to differential to be used with the balanced 3E DSP output?
I believe I read somewhere that they don't like load on just one channel, if so, how do people do when measuring drivers one at the time?

 

[utking]

Sure, here the link to the Golden version :

Shui yuan Audio TPA3255 2.0 carte amplificateur numerique DC24 40v forte puissance elevee 300W + 300W classe D o carte amplificateur numerique | AliExpress

I am not fond of the A07.... the A04 with black PCB sounds better for me, I own both. The Shui yuan is better than the A07 from my point of view! more flexible, I find it sounds better too, it is great for DIY projects etc.

I hope you can confirm my opinion when you receive yours) did you read the review from my external contact ? > I loaned it to a colleague who compared it to the Jlester and the Hypex Ncore NC500MP.

I'm about to order the Shui yuan TPA3255, but do you know if it can be used with balanced XLR inputs?

 

[bushellj]

Hi Utking

This board is SE input only - There are no jumpers to set it for Balanced input.

You could feed a balanced input by removing the Op-Amps but then why buy this board !?

You will need something like the 3e-Audio board if you want to use Balanced Inputs.

James

 

[bushellj]

Sure, here the link to the Golden version :

Shui yuan Audio TPA3255 2.0 carte amplificateur numerique DC24 40v forte puissance elevee 300W + 300W classe D o carte amplificateur numerique | AliExpress

I missed that choice on some of the AliExpress options !! Didn’t seem to be an option when I purchased mine. Maybe just a new batch of boards and that was what was available. Everything else looks identical.


Clearly the “Golden” one is going to sound better and hence the increase in price !!

The two heat sinks look identical in size from the photos. The silver one is heavier material but less fins. The “Golden” one is lighter weight but has more fins. I would probably stick with the silver one unless your vanity overcomes you !!

 

[daniboun]

LOL : Marketing ) Gold vs Silver
the Chinese are not lacking in imagination)

Keep me posted when you get yours )

 

[daniboun]

Amigos,

If someone can find the link to this TPA3251 module please MP me !
I am looking for this board but can't get the link anymore to Aliexpress. Many thanks

 

[denbret]

Hello everyone,

I have a Meanwell 36v 11A SMPS, I was thinking of adjusting the voltage to 40vdc, is this a good idea?

Although I don't need any extra power, currently I have the MA12040 and the power of 30w / c 4ohms is more than enough for me.

I should receive mine soon (silver rad ), I am waiting before ordering new capacitors from Mouser.

 

[mamocel]

Amigos,

If someone can find the link to this TPA3251 module please MP me !
I am looking for this board but can't get the link anymore to Aliexpress. Many thanks


https://ibb.co/zS3hvJ7
https://ibb.co/gDHrLqF
https://ibb.co/PmLYFHN

Not found either, but the
op amp seem welded, too bad.

 

[daniboun]

Indeed but the PCB and components seem absolutely great )

 

[ilan5555]

Dear friends,
I bought an amplifier board from DrMordor.
I think that it doesn't fit to my speakers.
It's completely new, worked for 1 hour.
If someone wants it, it can sell it for half the price.
Please let me know and I can send it in 24 hours.
Thanks.

 

[daniboun]

Dear friends,
I bought an amplifier board from DrMordor.
I think that it doesn't fit to my speakers.
It's completely new, worked for 1 hour.
If someone wants it, it can sell it for half the price.
Please let me know and I can send it in 24 hours.
Thanks.

Hummmmmm I am really surprised to read this
Could you please explain what you feel ? What about your speakers ?
Where are you from by the way ?

 

[ilan5555]

There is a lack of body and texture.
The bass is a bit tight.
For me, it's too bright.
I have Paradigm Prestige 95.
I'm from Israel.

 

[daniboun]

really weird... 94DB (+/- 2 dB) 37 Hz  -  20  kHz, they are close to mine...
Yet DrMordors have a very good reputation ...
You might feel the same with any other TPA325X chip, if I were you : I would go for another way.

You should try some Hypex Ncore NC252, this could be a good alternative.

 

[ilan5555]

I bought from 3eAudio and it had more body than this one.
Strange.
When can I buy an Hypex Ncore built board?

 

[chips666]

There is a lack of body and texture.
The bass is a bit tight.
For me, it's too bright.
I have Paradigm Prestige 95.
I'm from Israel.

Hi, strange
Are you sure that everything is correctly connected
I have the blackboard and i am really happy with it
Maybe it needs more time to settle
Goodluck
Enjoy...

 

[daniboun]

I bought from 3eAudio and it had more body than this one.
Strange.
When can I buy an Hypex Ncore built board?

MP me )
take a look here by the way (post 1849) :

Class D Amp Photo Gallery

 

[Deleted member 148505]

I bought from 3eAudio and it had more body than this one.
Strange.

You are included in the percentage of population that doesn't like PFFB sound.

Too much negative feedback kills the full bodied midrange sound.

You can fix it by reducing negative feedback of PFFB. Ask dr. Mordor for R_fb and R_fb_ground values for reduced PFFB.

Problem with non-PFFB TPA3255 is that it has a harsh 'sss' and 'cchh' sounds.

So with PFFB config, we want to get the best sibilance / highs while maintaining the full bodied midrange sound. (This is what I'm doing these days)

-----------------------
If Dr. Mordor's amp uses SLAA788A values, This one also helps in improving the sound

Reduce R_op-fb (depending on opamp feedback resistor)

Set cutoff frequency to >= 450kHz
RC Low-pass Filter Design Tool

 

[Deleted member 148505]

Disclaimer: Those are just crude measurements, I just poked the screw terminals with the oscilloscope probe.

So the ripple and noise rating on their datasheet should be better.

Checkout what Jlester measured :

Meanwell LRS-350-36 vs SMPS300RS (LLC)
Not sure that LLC provides a big difference... Both are reliable but unsuitable for my project.

I wanted to stay consistent with my specifications: a compact and efficient TPA3255, a compact and reliable SMSP LLC power supply. I think that with my modifications I found a good combo that fits my 131*249*55mm case.

Anyway :

the Meanwell has a higher switching noise (65kHz) (192mV-pp).
same ripple for both

https://ibb.co/rkYgBG1

 

[Mello4]

There is a lack of body and texture.
The bass is a bit tight.
For me, it's too bright.
I have Paradigm Prestige 95.
I'm from Israel.

Paradigm Prestige 95F input impedance drops below 4 ohms at the upper range. The Class D output filter may need optimization: Paradigm Prestige 95F loudspeaker Measurements | Stereophile.com

TI TPA3255 Application note....LC Filter Design (Rev. A)

Fig.1 Paradigm Prestige 95F, electrical impedance (solid) and phase (dashed) (2 ohms/vertical div.).

 

[Deleted member 148505]

did you read what I shared a few pages back ? This deals with Inductors + TPA325X.

checkout :

TPA3255 / TPA3251 / TPA3245 universel - un pour tous - #360customs

Yup, he just lifted the values from slaa701a.. or not? haha

As surprising as it may seem to you, I confirm that there is no pop when switching ON / OFF.

Small PVDD capacitance and small input dc blocking caps might have helped to remove the on/off pop.

Paradigm Prestige 95F input impedance drops below 4 ohms at the upper range. The Class D output filter may need optimization: Paradigm Prestige 95F loudspeaker Measurements | Stereophile.com

TI TPA3255 Application note....LC Filter Design (Rev. A)

Fig.1 Paradigm Prestige 95F, electrical impedance (solid) and phase (dashed) (2 ohms/vertical div.).

Yes this might be also the case, please check if 3e audio's module and dr. Mordor's module have different output filter values. TPA3255's passive PFFB will slightly correct the frequency response to a certain extent.