Hello! another new guy. Question about fitting the chassis into BBRI

[Thooly]

Hello there!

I'm a newbie here. I have enough knowledge to be dangerous as an EE. I built an 18watt single channel clone into a totally different, small chassis and cab. I preferred the trem channel sound. So I built that, a single input, trem channel clone with no trem. The plate resistance on that channel is HUGE so there is a lot of gain. It sounded great but it lacks balls, low end and punch. So i just always ran that as a head into a closed back 2x12 with greenbacks.

Then came hurricane Milton. My amp got drowned. Partially. I think the trannies are still good. But I have hammond trannies, so judge me silently.

BACKGROUND side-point: I bought a BBRI in the late 90's for Beano then needed to mod it because with my LP with PAF clones I could NOT get anything close to Beano sounds with it.

First thing to change was speakers. Greenbacks are not it. Celestion blues, alnico speakers get the sound! MUCH closer.

Second, I needed to use KT66s and then actually get the circuit to match the original schem and voltages from the Marshall book.

One major thing for me was that the stock PT in the BBRI gave a B+ that was far too low, like 375. It just didnt sound right.

So, long story short... I was successful after rebuilding the amp totally, matching the original schematic and getting the B+ to be closer to original spec. The B+ does matter a lot IMO. Very interesting.... Even at the same bias point, the stock 5881s in my amp sounded dull and lifeless at the 370V I was getting stock. Once you get 400V or more then it seems to come alive. Even the 5881s sound good.

But I use KT66s.

So right now.... I have an 18 watt that I want to rebuild with a chassis that can fit into my BBRI cab. AND my actual BBRI chassis which was original circuit BB needs to be redone, that got drowned even worse.

Ideally I want to be able to mount both chassis' into the BBRI chassis. I have a still good head cab for the Bluesbreaker chassis, so Im thinking of rebuilding that and keeping it in the seperate head cab. But I'd like to put the rebuilt 18 watt into my Bluesbreaker RI chassis. I KNOW it would sound great. Open back with 2 celestion blues, while I also have a 2x12 closed back bluesbreaker extension cabinet with 2 greenbacks. Best of both worlds.

So.... anyone have thoughts, advice, info if I can do what Im after?

[Graydon]

Hello and welcome to the 18watt group.
That's alot of options. First step is to decide which chassis you want in that BB cabinet and which one you want in a head. You can try both amps temporarily with the BB cabinet to see which one has better synergy with that cabinet. Likewise test both amps with the closed back 2-12 and hopefully that helpss you make the choice.

[Thooly]

Yes, thank you, of course. I have looked at the dimensions of the 18 watt chassis' that are available and they are way off from fitting the BBRI cabinet. So I'd have to find a chassis that would fit.

[JMPGuitars]

See if you can find a BBRI chassis that you can convert, or get one that isn't drilled out yet, and drill it out yourself.