Would it be a good idea to use a regular off the shelf SMPS used for LED lights with some added filtering for an audio amplifier or would that be too noisy without the added help of a linear regulator? I can't get a hold of any power transformers that would be affordable for me and I know that supplies such as PC power supplies are too noisy without a lot of added filtering from experience but before I dive into the idea is there anything else I need to know about cheap Chinese SMPS' used for LED lights?

 

Depends a lot on their switching frequency.
You would want that to greater than 20kHz to avoid a noise in the audio band.
But don't those designed for LED lights put out a regulated current, not voltage?

 

I'm referring to the ones like these: https://www.ebay.com/itm/DC-12-24V-...hash=item35fda85ec4:m:mFgM1Jc_OpjSQUEIv7z9fkQ
Since they're cheap and abundant but in terms of quality I'm unsure. If anyone has had any experiences with these kinds of supplies it would be nice to know.