Advice Sought about possibility of Balanced Input Power amp

I can't believe this info isn't available somewhere but I've spent several days trying to find it.

I have an ageing AVR that isn't much use to me any more, not really interested in surround sound movies, no interest in going to atmos. So I'd like to get rid of it and have better sound, especially surround sound audio. Main speakers are Kef iq7, also have cheap centre speaker & decent rear speakers, which I'd like to keep for the time being and consider replacing in the future.
I have a spare Raspberry Pi no longer used from another project which I'd like to utilise with CamillaDSP for output.
I'm interested in purchasing a Topping DM7 8 channel DAC. If I do, my use case would require several power amps (bi-amp front speakers, centre speaker, stereo rears) with balanced input, balanced because of the DAC output.
I'm OK at electronics, IOT devices, soldering etc. Own an oscilloscope, own and read a couple of Douglas Self's books. Have had a long-term wish to self-build some amps, which I've never done.
My question, which I'm finding pretty hard to answer for myself: Is it reasonably do-able to build any of the forum amps, (eg the Wolverine amp but any others might do) with XLR/TRS balanced input or with some kind of balanced input stage before the amp proper?
 
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I'm a big fan of Neutrik products, but that transformer doesn't really meet the hi-fi standard. I think it was created as a cheap stage stopgap. What you could use is eg. a Jensen transformer but then you will easily pay 10 times the price. Good transformers are expensive..

Hugo
 
The CA-V2 amplifier design on the Dutch forum zelfbouwaudio.nl/forum has a balanced input by design. I don't know much about it, except that the designer knows what he is doing.

https://zelfbouwaudio.nl/forum/viewtopic.php?p=1977648#p1977648

Unfortunately it's a composite amplifier with an LM3886, which are out of stock until October (or even later, depending on the package).

You can also put a differential amplifier consisting of an op-amp and some resistors and capacitors before the unbalanced input of any amplifier. It's a lot cheaper than a really good signal transformer, especially if you can tap off the supply voltage for the op-amp from the amplifier.
 
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