TPA3255 - all about DIY, Discussion, Design etc

I just finished wiring up my 3e Audio/Meanwell build and I’m pretty happy with the results.
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The amp is dead silent and sounds fantastic! I may need to add a small fan though since the power supply gets pretty hot when driving my big 4ohm floorstanders. I noticed the Meanwell rps400 is only good for 250w if no fan is used.
 

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I just finished wiring up my 3e Audio/Meanwell build and I’m pretty happy with the results.
View attachment 1076477
How's the temperature of your 3E? I cannot drive the 3E in a closed enclosure w/o forced air, not at 48V. The amp draws about 130mA in Idle, that's nearly 6W, which translates to ~52C for my ambient temp which is pretty hot right now ~25C. I had to drop to 32V to remain within 40~45C.
I have a similar housing but I'm using a Nobsound SMPS. These types of PSUs, housed in a "half a box" of aluminum, can thermally attach to the side panel which is a hefty heatsink and solve the PSU thermals. I still have a problem unsolved for the amp, the caps are getting very hot and its a bad recipe for the long run. Caps derate badly with temp and this is also bad news for the cap/coil ESR. I think you'll need forced air for the sake of the amplifier at least if no more than the PSU. I'm the same boat and the AC is broken 😎
 
Hi everyone!

A year ago I made an assembly based on the 3e Audio TPA3255-2CH-260W (version B) board and Conex 300RS 36V (here it is) .
In the meantime I replaced the Ti5532p with OPA1612 and changed the cables between the RCA plugs and the board pins.
Overall, I'm very happy with it all.

Now I will switch to balanced, and a Connex 600RS 48V. and I have a few questions:

- When switching to balanced input, should I change the OPAs? Or do something special besides move the jumper? I've read a bit of everything and its opposite on this and am quite lost. Nothing indicates anything of the sort in the documentation or on the Audiophonics site for example.

- Does anyone know the Input sensitivity of the 3e Audio TPA3255-2CH-260W (version B) in Balanced (without pffb)?
 
I didn’t measure the ripple but I wouldn’t expect much difference with and without the capacitor. If I have some free time this weekend I’ll measure it and let you know. I added the capacitor more for energy storage and to reduce the likelihood of bus pumping.
 
Hi everyone!

A year ago I made an assembly based on the 3e Audio TPA3255-2CH-260W (version B) board and Conex 300RS 36V (here it is) .
In the meantime I replaced the Ti5532p with OPA1612 and changed the cables between the RCA plugs and the board pins.
Overall, I'm very happy with it all.

Now I will switch to balanced, and a Connex 600RS 48V. and I have a few questions:

- When switching to balanced input, should I change the OPAs? Or do something special besides move the jumper? I've read a bit of everything and its opposite on this and am quite lost. Nothing indicates anything of the sort in the documentation or on the Audiophonics site for example.

- Does anyone know the Input sensitivity of the 3e Audio TPA3255-2CH-260W (version B) in Balanced (without pffb)?
To switch to balanced input on the 3e audio board you simply move the jumper to the correct position, wire up your Xlr connectors, and your all set.
 
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Hi, for trying.
The best option is XLR...
In short and long distance pro audio, they only use this.
I thought that for a home HIFI set, it was useless .... big mistake on my part.
these class D chips have balanced inputs as much as used, I think these chips are optimized in this sense
The signal to noise ratio is much better!
A good DAC, even cheap, should have these outputs...

Make the right choice....I'm done...🙂🙂🙂
 
I didn’t measure the ripple but I wouldn’t expect much difference with and without the capacitor. If I have some free time this weekend I’ll measure it and let you know. I added the capacitor more for energy storage and to reduce the likelihood of bus pumping.
A full bridge class D amplifier (3e runs the 3255 in BTL mode) does not suffer from bus pumping, at least not to extent to warrant a huge bank cap. Typically bus pumping is caused at low frequencies for half bridge designs, if this is really a concern I'd suggest measuring the supply with a sub-100Hz say a 60Hz tone audio signal. You got me puzzled so I'll measure as well the supply on my 3e amps 😎