Hello all. David Seymour here. Long-time stalker, first-time poster. My current project is a bass guitar combo amp using this Sunn 200S preamp from EffectsLayouts.com coupled into this cheapo Chinese mono power amp stage. Meant to be small enough for solo practice and lugging around, but powerful enough for small ensemble gigs, maybe even with a modest drummer. Heatsink, cabinet design, and 8Ω speaker selection is done, but I need help figuring out the power supply. I'm definitely not a qualified electrical engineer. I'm handy with schematics and a solder station, but I know better than to mess around with power mains.
The Sunndering preamp is designed for DC 9V, presumably 500mA is plenty. The Chinese power amp PCB says it accepts wide power supply range, dual voltage DC +/- 20V-90V (not sure what that additional 12V input is on the bottom right.) I'm thinking 200W, 45V or 60V would be best, right? Trying to keep costs down; it's a bass guitar amp, after all, not a HIFI or audiophile grade application.
Is there such as thing as a ready-made solution for this? If not, can anyone point me to some existing DIY solutions, schematics, BOMs, etc? If not, who is able to design such a thing for cheap?
Thanks and cheers! 🍻
Preamp stage:
200W Power amp stage:
The Sunndering preamp is designed for DC 9V, presumably 500mA is plenty. The Chinese power amp PCB says it accepts wide power supply range, dual voltage DC +/- 20V-90V (not sure what that additional 12V input is on the bottom right.) I'm thinking 200W, 45V or 60V would be best, right? Trying to keep costs down; it's a bass guitar amp, after all, not a HIFI or audiophile grade application.
Is there such as thing as a ready-made solution for this? If not, can anyone point me to some existing DIY solutions, schematics, BOMs, etc? If not, who is able to design such a thing for cheap?
Thanks and cheers! 🍻
Preamp stage:
200W Power amp stage:
That power amplifier barrier strip is for input from a wall wart of 12-15 VAC.
Also it could take 17-21 VDC instead. In that case, polarity is not a concern because of the bridge rectifier.
Maybe that supply operates the output speaker relay, try it and see.
Also it could take 17-21 VDC instead. In that case, polarity is not a concern because of the bridge rectifier.
Maybe that supply operates the output speaker relay, try it and see.
That seems a good guess. Now that you mention it, the non-upgraded version of this power amp PCB, which doesn't have the speaker protection relay, also doesn't have the separate 12V hookups.
Non-upgraded PCB: