TPA3255 - all about DIY, Discussion, Design etc

[daniboun]

Hi,

Just received today my TPA3255 power amp module and a few days ago my 600W 47Vdc supply from Cresnet. These 2 items will fit nicely in a enclosure from eBay, do a search w 1907 enclosure. Once I have received my enclosure I’ll post some pics. The 3e Amp is surprisingly small...For now, this is what I have;

Great looking forward to see the final result
Do you refer to this enclosure ?

https://www.google.com/url?sa=t&sou...Vaw2b1TgyROBX2RKFHTQsC16S&cshid=1582703797788

 

[e_fortier]

Yes, it’s the right enclosure.

Maximum height of 600W Cresnet power supply including stand-off is 55mm and the 1907 enclosure shows an internal height of 63mm.

BR
Eric

 

[daniboun]

Yes, it’s the right enclosure.

Maximum height of 600W Cresnet power supply including stand-off is 55mm and the 1907 enclosure shows an internal height of 63mm.

BR
Eric

Looking forward to see the finished DIY amp )

 

[e_fortier]

Actually the enclosure I bought is 2U in height since I didn’t know the height of the SMPS I bought the following which is slightly higher and wider.



BR
Eric

 

[jimk04]

3e Audio 3255 observations and questions

I have had my 3e 3255 stereo amp in place since Septembee 2018. Running at 40v with 40kuf capacitance unregulated PSU.

It was never put into a box so I thought I would take it all down and house it properly. I also have a new 35v trafo, LT4320 based ideal rectifier and new caps for the build.

I thought I would recap the amp board as it has been powered 24/7....and well....we like to recap things dont we.!

The 3e board has 4x 1000uf 63v caps. Looking at the Ti 3255evm schematic, they employ 2x 4700uf caps for the main 'PVDD' power input. So the 3e board is a way off there. I shall attempt to add more capacitance but there isnt much room for anything more than 16mm diameter caps, best I have found is either 1200uf Panasonic FC 105degree or 1800uf Wurth 85degrees. I plan on removing one of the green cable clamps and adding a other cap there, so I shall get 5x caps on the board.

Maximus I could end up with is obviously 6000uf or 9000uf for the Wurths.

What also interested me is looking at Ti3255evm having 4x 1500uf 63v electrolytic on the speaker outputs. (Part of the LC filter??). No sign of such on the 3e board. Just and caps and small tht films for the LC from what I can tell.

 

[saddevil]

What also interested me is looking at Ti3255evm having 4x 1500uf 63v electrolytic on the speaker outputs. (Part of the LC filter??). No sign of such on the 3e board. Just and caps and small tht films for the LC from what I can tell.

these caps are for decoupling DC voltage in 4channel mode

 

[drMordor]

Hi,

Just received today my TPA3255 power amp module and a few days ago my 600W 47Vdc supply from Cresnet. These 2 items will fit nicely in a enclosure from eBay, do a search w 1907 enclosure. Once I have received my enclosure I’ll post some pics. The 3e Amp is surprisingly small...For now, this is what I have;

Warning!!!

 

[e_fortier]

Is there some components missing?

I’m expecting my case tomorrow.

Thanks
Eric

 

[jimk04]

Well spotted....yes indeed small film cap missing.

Please note my PVDD caps and heatsink are removed here

 

[jimk04]

Actually I see you have just one missing. Compare the other side.

 

[e_fortier]

Thanks guys, only one missing but an important cap.

I’ll write to 3e.

 

[jimk04]

I know it isnt the point and assuming you are ok to do so but you may be better/quicker to fix the missing cap yourself. However I do agree that this needs to be bought to 3e Audio attention.
I have 2 of their amps..bought in 2018....both nicely made. I saw a couple photos on the 3e group buy thread later on that seemed to portray a drop in quality control. I hope I am wrong.

 

[daniboun]

Hi amigos,

I found a pair of AOP Muse 02 and put it on my TPA3255 AIYAMA amplifier. (Full Nichicon)
I also add a 45/48V 500W PSU....

I can say wouaaaaaaaaaa ! I found the combination Muse 02 + TPA3255 incredible !

I listened to my albums in HD audio with a rediscovery of the details that did not appear before... I used before this a pair of AOP 1622 but finally the combo MUSE 02 + TPA3255 work so great )

Pictures of the Amplifier with old AOP + PSU

 

[saddevil]

Hi

Power amplifier ist finished..
- Input ist single ended and with OPA1632 OPV's
- added relais with power on delay and if TPA detects an error, output is switched off
- PFFB circruit
- hybrid output filter
- zobel filter
- one 12V regulator for VDD and gate drivers with additional LC filters, second 12V regulator for AVDD
- 12V regulators have no connection to PVDD .. must supplied by external power supply
- AGND is not directly couppled and isolated from PGND ( including AGND pins on TPA )
- 4 layer PCB ( added layer for PVCC and GND(s) )

Now i need a suitable preamplifier.
3 ideas.... I Hope Somebody can Help me ...

1: 5654W Tubes
+ H2 harmonics
+ tubelike sounding
- has to be changed after a certain time
- microphonics

2: Nutube passlabs buffer
+ H2 harmonics
+ tubelike sounding
- microphonics
- more expensive

3: JFET Like Nelson Harmonics Generator
+ H2 harmonics
+ tubelike sounding
- not tubelike enough?

My plan at begining was to add a tubelike "part" to get tubelike sounding... a little


an aditional part is Volumecontrol
I would use a PGA3210/20 ... encoderlike "poti" + small OLED ( 0,96" types )

 

[xrk971]

Hi Guys:
There is a shortage of 10uH SER290 Coilcrafts at the moment. What are your thoughts on substituting a 15uH, 30A (same series SER2915H-153KL). The 10uH's are back ordered until mid-May of this year. It can be compensated with a smaller value of the filter film capacitor I think.

Datasheet here:
https://www.mouser.com/datasheet/2/597/ser2900-270685.pdf

 

[saddevil]

Hi Guys:
There is a shortage of 10uH SER290 Coilcrafts at the moment. What are your thoughts on substituting a 15uH, 30A (same series SER2915H-153KL). The 10uH's are back ordered until mid-May of this year. It can be compensated with a smaller value of the filter film capacitor I think.

Datasheet here:
https://www.mouser.com/datasheet/2/597/ser2900-270685.pdf

How about Würth 7443641500 , 7443641000 , 74436411000


PQ2617BHA-100K Bourns Inc. | Induktivitaten, Spulen, Drosseln | DigiKey

Should be pincompatible

 

[e_fortier]

Hi Guys:
There is a shortage of 10uH SER290 Coilcrafts at the moment. What are your thoughts on substituting a 15uH, 30A (same series SER2915H-153KL). The 10uH's are back ordered until mid-May of this year. It can be compensated with a smaller value of the filter film capacitor I think.

Datasheet here:
https://www.mouser.com/datasheet/2/597/ser2900-270685.pdf

Hi X,

Here is the one used on the TI evaluation board TPA3255EVM...612 in stock.

MA5172-AE Coilcraft | Mouser

Maybe the one you are asking about a better quality one.

BR
Eric

 

[Dadbeh]

Connect to J10 and J12 headers (with J4 and J19 configured for "DIFF") as I mentioned here -
https://www.diyaudio.com/forums/class-d/314834-ti-tpa3255evm-86.html#post5728689

hey man. would you please help me with figuring out what kind of molex connector is needed and how to terminate it? J10 and 12 need these connectors and i dont know where to get them or how to terminate.

 

[linuxfan]

Molex 0022012037 or 22013037, with Molex 08500113 crimp terminals
0022012037 Molex | Connectors, Interconnects | DigiKey
https://www.digikey.com.au/product-detail/en/molex/0022013037/900-0022013037-ND/26433
https://www.digikey.com/product-detail/en/molex/0008500113/WM1114CT-ND/467980

I use a crude crimp tool, but you can get a nice one if you search eBay for "Molex crimp tool".

Or if this is too much messing around, just connect to the RCA connectors instead,
or maybe solder your input wires directly to the Molex pins.

 

[lithoc]

Hi,

I have a question regarding Chinese TPA3255 stereo amplifier.
I have a passive 4ohm single coil subwoofer I wanted to try on this amp

1. Can I use it as one channel as home theatre
subwoofer and leave the other channel unplug ?
Will cause any damage
2. Can I plug both RCA using Y split cable and connect the output as if it's parallel BTL (PBTL) mode?
Will it work ?

Need advice

Thank you