looking for opinions on amp design.

[armstrom]

To make a long story short, I picked up this power amp kit for $10 to meet a minimum order requirement . I wanted to see if I could get any opinions on the quality of the design. It's sold as a 30W amp and takes a single +50V power supply. The kit included a couple of heat sinks for the output transistors but I may upgrade to something larger. Here's a link to the instructions with a schematic. Note: The component values are not shown in the schematic (I guess they want you to buy the kit, since they are listed in the printed version of the document included with the kit).

Here's the document:
http://www.mr2-power.com/FK656E-1.pdf

I can supply specific component values if it would be helpful. This amp will eventually be paired-up with a suitable preamp stage and pushed into service as a guitar amp.

So, am I giving up anything by using a circuit with a single positive power supply rather than the typical bipolar supplies you see on amps like this?

I plan to build the amp regardless (it was only $10 after all) but I would like to know what I'm in for as far as sound quality and robustness of the design. Keep in mind that as a guitar amp Hi-Fi/Audiophile like qualities (like S/N, harmonic distortion, etc...) are of less value than good tone and robustness.

Thanks in advance,
-Matt

 

[richie00boy]

It appears to be the classic single ended PSU amp. Nothing special, it will sound OK, it will measure not great. The main issue is the rudimentary output bias scheme and the output coupling capacitor value. However, the output coupling cap could be a virtue in a stage environment should the amp get blown, as it will provide a measure of protection to the speaker.