6G6-B blonde Bassman mods?

JohnnyCrash

Doctor of Teleocity
Joined
Mar 12, 2005
Posts
11,730
Location
Fullerton, CA
Update:

My daughter is happy and healthy!

Also, today, somehow, the tone goddesses granted me workbench time.

I finally got the right capacitor (0.022uF) onto the Bass channel’s 250k volume pot’s DPDT switch. I’m calling it THE 6G6-B DAPHNE MOD :)

The Daphne Mod does exactly what the huge Marshall plexi caps (4700pF — AKA 0.0047uF) do across their 1 meg volume pots. I gave it the paces and actually had a good night’s sleep… much better cognition and hearing.

Tested, tested, and tested again. Volume up to 2, cap switched on, switched off. Volume up to 4, cap switched on, switched off… etc.

The cap, as expected, sounds completely out of the circuit when on 9.5-10. At lower levels though, like the plexi cap, it throws a good amount of mids and upper frequencies (and volume, giving less control over the actual volume knob — it goes zero to sixty quick) right past the volume pot and directly at the next stages. This works great for tweaking gain back and forth with the next stage (controlled by the Bass channel’s Treble control, as 6G6-B circuits do), then with the Treble control and the PPIMV control/power tubes. It helps me find a sweet spot for gain and power amp oomph at various volumes (and even decent compromised tone at extremely high gain preamp settings with the PPIMV set extremely low for very quiet playing).

Edge of breakup, clean and snappy (but a little mid-fat like tweed and brown/blonde era amp circuits), or filthy… pick sensitive and dynamic. Even with the Bass control low on the Bass channel, my 2x10” cab sounds like it has the bottom end of a Marshall, so I understand the comparison. The low frequency/high frequency gainstages react in a very cool way on 6G6-Bs.

I can’t wait to plug my SurfyBear reverb unit into it!
 
Last edited:

tubeswell

Friend of Leo's
Joined
Jul 1, 2008
Posts
2,495
Location
NZ
I like the 6G6B stock circuit. Its a nice clean amp but the bass channel has a funky blues sound when cranked past about 7. I built one a few years back - left it stock. Now and again I run it through a '73 Dual Showman Reverb cab (2 x 15" Orange Frame D130Fs) for surf and rock'n'roll.
 

JohnnyCrash

Doctor of Teleocity
Joined
Mar 12, 2005
Posts
11,730
Location
Fullerton, CA
The Daphne is officially complete. Just installed some amp badges.

CC500CDB-68BB-4575-A6EF-B27E982F6044.jpeg
 

mountainhick

Tele-Holic
Joined
May 2, 2021
Posts
525
Age
65
Location
Rocky Mountains
I’m excited to see a micro version!
It lives!

Made it through startup and already had to tweak a bit for proper voltages, now to start putting through the paces with a few guitars.

I think my micro has different sound quality because of a SE power section.

I guess I should post a new thread...

Might have a go with the Daphne mod!
 




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