Post by doveman on May 24, 2012 6:12:09 GMT -7
I finally feel like I'm getting in the zone. I bought a RT66 head and it's been a mystery to me so far ... it sounded good at very low volumes but when I'd crank it up it seemed a bit harsh and clangy. I could get it to sound better at very loud volumes but still I was working way too hard. Combining that with the fact that it's really loud, it was frustrating me. I tried a Brake Lite but if the amp's not sounding right, that really wasn't going to make it better ... had to get the amp sounding right first.
Anyway:
A couple of things I will do shortly:
So ... feeling better. The amp has a much better feel to it. I remember be really disappointed in my tweed when I got it ... a few tweaks and a little work and it became awesome. I think this will be good.
Thanks for the help everyone! ;D
Anyway:
- Installed bias points inside the amp ... it was a bit cold ... turned it up a little hotter.
- Replaced the 12AX7 PI ... that helped too. EDIT: Put it back ... don't think there was really a change.
- Brake Lite sounds pretty good now ... the amp underneath had to be right first. I think I'll give this a whirl for a while before considering the VVR I mentioned.
A couple of things I will do shortly:
- Order some 1% 1-ohm bias resistors to be sure my new bias points are accurate (I had to screen 5% resistors locally to find two that measured 1-ohm). I'd like them right and they are cheap and available to order.
- Get another set of tubes ... backup ... plus see how they sound. Another EF86 and a set of Gold Lion KT66. A little "tube rolling" ... leave in the best ... keep the others as backup.
- I would like to understand why the 5U4GB as it drops the pin #3 voltage to 440V DC cannot be biased up to 70%. Maybe running at 60% would work ok ... but that's for future tweaking.
- I decided to hook up my 2x12 (G-1265/M75) cab as a 4-ohm cab w/Brake Lite mounted inside ... probably today.
So ... feeling better. The amp has a much better feel to it. I remember be really disappointed in my tweed when I got it ... a few tweaks and a little work and it became awesome. I think this will be good.
Thanks for the help everyone! ;D