Ever Recycled a Pre-amp From an AVR for DIY Power Amp (Audio)

[ZoSoNCSU]

Anyone ever recycled a pre-amp from an AVR to use with a custom/DIY power amp design?

My DAC consists of an ES9028Pro + Amanero (32bit/384kHz & Native DSD up to DSD512) w/ TCXO Golden Oscillators on the way for a small upgrade on the Amanero).

I am also doing a quadraphonic MX50 SE x4 (mono-block style shown below). I haven't found any preamps up to my standards that are available as kits or even just a labeled PCB haha, if anyone has a schematic to recommend please do!!

If not I am going to take my Dremel tool with a carbide cutting bit and cut this sucker up so I can tap each pre-amp individually.

 

[Soldermizer]

Your goals (and skills) are far above mine I look foward to hearing of your results. I own an inexpensive HTR (collecting dust). They offer so many options for audio. While I went for separate amps, they must be usable for lower-powered multi-amping a pair of speakers. If you feed it with (e.g.) HDMI from a suitable media PC, you don't even need any other hardware between the PC and the speakers.

 

[dotneck335]

One caveat: many old AVR circuit boards have become very brittle with age, and crack easily. This happened to me when I tried to recycle one. Perhaps if you are VERY gentle with the old board, you won't have this problem.

 

[ZoSoNCSU]

Now the trick is going to be figuring out which trace is what, at least it's not a multi-layer PCB.

Note: I tried to cut this preamp with a circular cutting disk for wood and it was barely moving due to the metal found throughout the cut. I immediately switched to my carbide cutting bit with my Dremel 4200 w/ Flexshaft and that made it easy cutting. Also.... ALWAYS WEAR EYE PROTECTION DURING CUTTING!!

 

[phase]

That’s pretty cool. I just saw a $4K Marantz amplifier that had some glitch in the display or something for $200 on CL, had ten pairs of mt-200 outputs, was tempting to use for an amp project...

Good job recycling that stuff!