I picked up this old RCA PA in great shape. Tube lineup was 5Y3, 6L6x2, 6SL7, 7025, 6AU6. I've turned a few old PAs into guitar amps for friends, but I've been touring on bass for the past few years, so we all know where that was headed...
Measured voltages, kicked around ideas, and settled on a single channel B15N. After some cleanup, I was able to reuse a lot of parts - tube sockets, transformers, pots, some coupling caps, some resistors, etc.
I decided to pull the 7025 & 6AU6 (they'll go into another project, of course) & add an extra octal socket to use a proper 6SL7 as V1 - easy job as the amp already had octal-sized cutouts for the (non-existent) mic transformers. This is my first foray into octal pre tubes, and I'm hooked. Such rich tone coming out.
Next addition will likely be a transformer DI out, using one of the existing XLR jacks from the original PA. I'm tempted to add a switchable dummy load and a post-OT DI for maximum tube tone...
Measured voltages, kicked around ideas, and settled on a single channel B15N. After some cleanup, I was able to reuse a lot of parts - tube sockets, transformers, pots, some coupling caps, some resistors, etc.
I decided to pull the 7025 & 6AU6 (they'll go into another project, of course) & add an extra octal socket to use a proper 6SL7 as V1 - easy job as the amp already had octal-sized cutouts for the (non-existent) mic transformers. This is my first foray into octal pre tubes, and I'm hooked. Such rich tone coming out.
Next addition will likely be a transformer DI out, using one of the existing XLR jacks from the original PA. I'm tempted to add a switchable dummy load and a post-OT DI for maximum tube tone...
