This is interesting. Perhaps the KTB is not completely "off" even when not playing music.
My 3eAudio TPA3255 board ran really warm when is was using his 48V PS so I dropped to his 36V PS and now it’s only warm when playing for hours. My listening levels, through relatively efficient 8 ohm speakers, didn’t sell me on the notion that a more powerful PS produced any better musical reproduction (to my older ears).
Cheers, Pete
Cheers, Pete
Yes I am using the 48v PSU and it may be a combination of factors. It seems there was a few people who had thought it sounded better with the higher voltage but I am also dubious. I don't need the extra power and wish now that I had of gone with 36v.
I can report that my proposed solution has worked for my setup (RPi running volumio). The amplifier switch plugin for vulumio is set to inverted mode so the GPIO pin of your choice on the RPi goes low when music plays. I have a 1k resistor between the GPIO pin and the base of the (any old) transistor. The Emitter is connected to gnd pin on the 3e 3255 amp board and the Collector connected to the reset pin. When no music is playing it holds in reset mode and runs very cool. When music plays the connection between the rst and gnd pins is lost and then the amp heats up. The plugin allows you to set a time delay (in milliseconds) before it goes back into reset mode. Simple solution but dependent on software.
I'm still not sure exactly what the reset mode is doing exactly but must cut most of the power to the chip.
I can report that my proposed solution has worked for my setup (RPi running volumio). The amplifier switch plugin for vulumio is set to inverted mode so the GPIO pin of your choice on the RPi goes low when music plays. I have a 1k resistor between the GPIO pin and the base of the (any old) transistor. The Emitter is connected to gnd pin on the 3e 3255 amp board and the Collector connected to the reset pin. When no music is playing it holds in reset mode and runs very cool. When music plays the connection between the rst and gnd pins is lost and then the amp heats up. The plugin allows you to set a time delay (in milliseconds) before it goes back into reset mode. Simple solution but dependent on software.
I'm still not sure exactly what the reset mode is doing exactly but must cut most of the power to the chip.
Last edited:
New to TPA3255
Dear friends,
I'm new to all this things and I'm trying to learn.
I bought this amplifier:
TPA3255 2x260W 2Ch Class D Audio Amplifier|Amplifier| - AliExpress
Which is very nice.
It lacks the crisp and delicate highs but it's excellent.
I saw this review:
The amplifier instaled, instead of the board on sta516b from the expensive brand. This is a great amplifier!!! 3e-rulit! P.S. The Truth first threw out incomprehensible Oh with the marking of the type NE5532! and of course replaced all the containers with the original ones. Now the opa627 is from the Mauser and the Elna II tank from elitan, well, Kanesh shunty film. B. P. Linear without snowflakes and sprockets from capacitors. The sound is super!!!
Can someone explain what this man did?
The amplifier lacks a bit of details in the middle and it's not so full as my Denon 4700.
Thank you very much!
Dear friends,
I'm new to all this things and I'm trying to learn.
I bought this amplifier:
TPA3255 2x260W 2Ch Class D Audio Amplifier|Amplifier| - AliExpress
Which is very nice.
It lacks the crisp and delicate highs but it's excellent.
I saw this review:
The amplifier instaled, instead of the board on sta516b from the expensive brand. This is a great amplifier!!! 3e-rulit! P.S. The Truth first threw out incomprehensible Oh with the marking of the type NE5532! and of course replaced all the containers with the original ones. Now the opa627 is from the Mauser and the Elna II tank from elitan, well, Kanesh shunty film. B. P. Linear without snowflakes and sprockets from capacitors. The sound is super!!!
Can someone explain what this man did?
The amplifier lacks a bit of details in the middle and it's not so full as my Denon 4700.
Thank you very much!
It is probably because of your amps input. These amps are very transparent and whatever you are using to play your music lacks the detail in the middle or has too much highs. I tried an iPhone 8 and then my tv but these were to noisy. Then I used an iBasso DX160 but this was a bit bright but had lots of detail. Then a Khadas Tone Board and this sounded warmer and more analog. I am now using a balanced DAC and this has improved the bass and mids but I did modify my amp so I don’t know if it was just the balanced DAC. You get out what you put in. Your review looks like it is a translation, there is lots of info on this site about upgrading and modifying if that is what you want to do.
I’ll venture a guess... I bought that newer version board from 3eAudio a month or two ago. The board comes with one of three different 10uf 35V thru-hole caps..mine came with supposed Silmic II caps (but they weren’t brown) while the other two types are either Nichicon polars or the Nichicon non-polars (I’m guessing here: the green ones in the AliExpress photos are non-polar). 3e’s boards also came with NE5532 stock op-amps. I went to AliExpress and looked at the pictures the Russian gentleman posted with his review and it looks like he bought (guaranteed) silmic II caps to replace the ones that came on the board while also replacing the NE5532 op-amps with OPA627s (you can get pre-mounted ones from Cimarron Technology (search for browndog adapters). I can’t figure out the rest of the bad translation.
Cheers, Pete
D
Deleted member 148505
Try LM4562NA, it has very good highs while retaining the fullness of the sound.
Hi amigos,
Just to share with you : as you know I have tested lots of TPA3255 / 51 amplifiers here.
I own almost all brand and models. (3E Audio / DrMordor / AIYIMA / Zero Zone etc)
I have been testing now a double Mono Merus Infineon MA12070.
After a 5 days listening test, I can say you that this amplifier perform as well as the TPA325X with a deeper bass. The amplifier is absolutely dead silence, no pop sound.
I plugged back my Hypex Ncore to compare as well : This Merus is somewhere between Ncore and TPA325X, same bass as my Ncore and great SoundStage as my TPA325X. (ref board : DrMordor).
For those who ignore this new Merus chip, it is a great alternative to TPA325X or Ncore, take a look here for pictures :
Class D Amp Photo Gallery
Just to share with you : as you know I have tested lots of TPA3255 / 51 amplifiers here.
I own almost all brand and models. (3E Audio / DrMordor / AIYIMA / Zero Zone etc)
I have been testing now a double Mono Merus Infineon MA12070.
After a 5 days listening test, I can say you that this amplifier perform as well as the TPA325X with a deeper bass. The amplifier is absolutely dead silence, no pop sound.
I plugged back my Hypex Ncore to compare as well : This Merus is somewhere between Ncore and TPA325X, same bass as my Ncore and great SoundStage as my TPA325X. (ref board : DrMordor).
For those who ignore this new Merus chip, it is a great alternative to TPA325X or Ncore, take a look here for pictures :
Class D Amp Photo Gallery
D
Deleted member 148505
What is your room / ambient temp? After you removed the opamps you also reduced the losses on 15V and 12V regulators. Those regulators were significant source of heat on idle. It will heat up the PCB which will also raise the temp on TPA3255 IC.
But maybe yes there might be some oscillation from the opamps on your previous setup.
Hi daniboun,
Thanks for sharing this, I probably wouldn’t have spotted these boards on another thread as I’m new to looking at diy amps & thought I’d settled on the 3eAudio 3255 boards.
I’m in the early stages of planning a 6 channel amp to drive the base layer surround channels in my ever expanding Atmos system, I am leaning towards three, 3eAudio tpa 3255 with three Meanwell lrs-350-48 power supplies.
I’d really appreciate any advice or thoughts on this configuration.
Cheers all
J
That´s my experience with the TPA3251 too which is just down to quiescent current/Pd.
If the amplifier is hot at idle, or cold, there could be a problems.
I´d guess the way the heatsinks are mounted on a lot of these boards is less than optimal. It´s mechanically very tight to fabricate/mount a heatsink that sits absolutely even on that small pad of the chip.
Most heatsinks are only secured with 2 screws that are quite a few "thermal-pad-lengths" away from the thermal-pad.
To do a really good job the whole mechanic will have to be a really good fit and the mounting/screwing done with a torque-wrench. Application of thermal paste/thermal pads, is yet another story.
And then of course the parts are shipped around the world and banged around in their little packages.
Mine (Aiyima A04) were actually quite well done, although I´m sure nobody uses a torque-wrench or measure the flatness of the heatsink or similar.
As we all mostly listen to less than a couple watts though it´s really not that important ;-)
It´s so funny that most people get nervous when a heatsink is a warm.
It just goes to show there is a good connection from the chip to the heatsink.
(assuming you have at least some power dissipated)
I would rather get nervous if it´s cold. Then there isn´t a good connection and the chip could die quicker than the blink of an eye.
It just goes to show there is a good connection from the chip to the heatsink.
(assuming you have at least some power dissipated)
I would rather get nervous if it´s cold. Then there isn´t a good connection and the chip could die quicker than the blink of an eye.
Last edited:
To be honest, i wasn't very concerned about the heat given off by the hratsink... It was doing its job. Yes I concur that my CPUs, on my motherboards, get & run hotter than that and they are fine. The inductors got unbearably warm (yes little chance of them having any damage). I was just worried about all that heat decreasing the life of all the other components on the output side of the amp pcb... I probably shouldn't be since i change amps more frequently than i should... LOL
Pete
Pete
I use the same one as Audiophonics, but in Version 1.3 (VS 1.2). It is fully balanced.
They sound awesome, anti pop, easy to setup. But you need to use little wires because of those push connect buttons.
I mounted it reversed as you can see, heatsink as support.
Last edited: