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TPA3255, TPA3251 with Post Filter Feedback(PFFB)

Hi.

Yes, it is SMPS 600R2 version. These additional capacitance pcb boards I use for another amplifier project, but found it very versatile. I use Nichicon FW 1000uF/470uF, KZ 100uF and Mundorf 1 uF MKP capacitor. The goal was to lower SMPS impedance and provide additional filtering at higher fq.
 
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Hi.

Yes, it is SMPS 600R2 version. These additional capacitance pcb boards I use for another amplifier project, but found it very versatile. I use Nichicon FW 1000uF/470uF, KZ 100uF and Mundorf 1 uF MKP capacitor. The goal was to lower SMPS impedance and provide additional filtering at higher fq.
Thank you, Supernet. I just ordered two 480-1 units as well. While I wait for them to arrive, I need to choose a power supply. I like the 600R2, but it's on backorder.
What do you think about Meanwell?
There's an LRS-600N2 version that supposedly offers more power during peak demand.
or do you have any other recommendations?
 
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@audiomovil

My plan is to use a pair of Meanwell UHP-500R-48 power supplies and balanced input from my Parasound P6 preamp.

I don't know if the Meanwell UHP-500R-48 power supply is the best choice, but Mouser and Digikey have them in stock and they are known good sources. The idea of picking a rando power supply off Aliexpress makes me anxious. I hear good things about Micro Audio SMPS's, but they are more expensive and the lead time is longer.

Also not sure if a 48 volt 500 watt power supply is needed per channel (overkill) or if 48 volt 350 watts power supply per channel power supply would be enough.

What are other peoples plans for power supplies?
 
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Thank you, Supernet. I just ordered two 480-1 units as well. While I wait for them to arrive, I need to choose a power supply. I like the 600R2, but it's on backorder.
What do you think about Meanwell?
There's an LRS-600N2 version that supposedly offers more power during peak demand.
or do you have any other recommendations?

Keep in mind that Meanwell is regulated power supply and Microaudio is non regulated. I tested 3e modules with one regulated SMPS, but I prefer Microaudio. The latter has much better bass response, with depth and teksture. I found out Microaudio SMPS also has better 3D stage and midrange/tweeter area.
 
Keep in mind that Meanwell is regulated power supply and Microaudio is non regulated. I tested 3e modules with one regulated SMPS, but I prefer Microaudio. The latter has much better bass response, with depth and teksture. I found out Microaudio SMPS also has better 3D stage and midrange/tweeter area.
Hello Supernet,

I didn’t realize there was a difference between regulated and non regulated power supplies. I never paid much attention to it, so thanks for the insight!

I was considering getting two Meanwell units—one for each 3e module—but using a single Microaudio SMPS600-R2 would simplify my project.

If Microaudio takes too long to restock, could you recommend an alternative option, please?
 
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Good morning 🙂

It's going in the right direction BUT:

you have plenty of room to put a balanced volume potentiometer and remove all the 'horrors' on your input signal...
... you just risk gaining a LOT in SQ 😎

If your source really does not have balanced outputs then use a cable that allows RCA to XLR: you will certainly not have 4 volts at the input but 2 volts, however at least you will have removed a whole 'heap' of circuits that are sources of failure, of 'noise' and so on and ESPECIALLY the transformer which feeds all this 'bazaar' 😱

You will thank me later 😉

Regards.

PS: given the layout of your circuit, it would be in your best interest to wire the output of your DC power supply DIRECTLY to your amplifier PCB.

This would have the effect of shortening the link as much as possible, which is much more beneficial and would 'capture or broadcast' less noise or interference once again 👍

To further improve this, you can twist the wires very tight and make a 'shield' over them as I have shown in previous posts.

I say that but I said nothing... 🙄

2 questions:

1) Is it better to run and SMPS external to this Board and an all aluminum alloy case, or mount inside with board?

2) Without having to do anything to this PCB, can an Alps 50K pot just be placed between XLR connections and this board?

Thanks all.
 
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Thank you 3e. What would be the best value Alps pot to go with? (I have a spare 50k, but want the best option)
As I'm reading up all the posts here, I believe I'll have to use a 4-gang pot with XLR sockets?

I Would need a basic diagram assisting the hookup. Thanks in advance.
 
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I found this thread and assumed I would need 4 gang pot since XLR needs + and - signal attenuated for each channel?