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Hi,

I've been reading a lot about how much PSUs affect sound quality.
Obviously a linear PSU reduces noise that may end up in the audio signal in the end.
But it seems all mentioned linear PSUs are 5V and don't have too much ampere / watt, which is enough to power a Raspberry Pi, but not an amplifier.
I own a Hifiberry AMP2 that features a built-in 60W amplifier and also transforms the input DC to 5V DC to power my Pi.
So I am wondering if there are any (affordable) linear PSUs that deliver about 20V (max 24V for the AMP2) and 60+W (some extra watts would be nice since power ratings are usually peak and not sustained) that could be used to power my setup?
And also, does a linear PSU really make sense for the AMP2? Or does the integrated DC-DC conversion to 5V for the RPi introduce noise itself and a good (and possibly expensive) PSU would not have any effect on sound quality in the end?

Do any of you have experience with different PSUs and the Hifiberry AMP(2)?
What PSUs are you using with the AMP(2) or which would you recommend for me?

Right now I am using a 19V Meanwell switching PSU, but I'd like to know if a better PSU may improve my sound quality. I don't really have anything to compare or a reference, but I am willing to try a different PSU if it makes sense.

Peter
Hi moOde fans,
Hi Peter,

I also use the AMP2 (have 2 in use) for more than a year.

The reason for my decision of RasPi and AMP2 (or any other HAT amp brand) instead of using a DAC and an analog amplifier (or active speaker) is: You have a complete digital connection from the source to the speakers. With the exception of the low-pass filtering at the end.

From this point of view, the PSU can not affect distortion, noise, or sonic changes as long as the components are working properly and the PSU is stable under all circumstances.

But .... while I tested some PSUs, I heard some (very small) differences in dynamics that - I suspect - are related to the speed of power delivery. A laptop charger - as an example - can deliver 19V / 4.5A over a relatively long period of time. This is different than supplying high current for a short audio pulse!

I'm currently trying a capacitor block after the PSU and will report if it brings an advantage.

But in my opinion, we are discussing here at a very high level.

Best Regards
Norbert
Thanks for the replies!
The PSUs from audiophonics.fr are mostly 5V and suitable to power a RPi alone, the most powerful has 60W, but the price of 200 Euros is quite a lot.
As Norbert said, with the AMP2 the impact of the PSU is different than for normal DACs, and the theory that the PSU should be suited for quickly changing loads makes sense to me.

I am really looking forward to hearing about your capacitor tests, Norbert! Please keep me updated.