Red Knob Twin Conversion Done!

[Dagan8]

Hello everyone.

I just wanted to post this mainly to thank all of those who helped me through the process of converting my Fender Red knob Twin into a hybrid Tweed/Black Face/Red Knob. It turned out great and it sounds good too! I was amazed how quiet it is.

BEFORE:
Fender Red Knob Twin 100W



AFTER:
Fender Tweed Face 50W



New amp features:
Channel One
-BF Deluxe voiced AB763
-Added mid control
-One input (HI)
-Reverb w/Foot Switch

Channel Two
-Tweed Bassman voiced 5F6A
-Three inputs: Norm,Link,Bright (HI)
-Presence control is global for both channels

Power Section and Reverb
-Reverb circuit components modified to BF values (Reverb only on CH1)
-FX loop still functions
-Bassman OT 50W
-2 6L6's instead of 4
-Circuit components modified to BF/Tweed values

I am currently in the process of adding a "Sag" resistor in the B+ rail. Since I had the chassis out of the amp again I thought I would snap the photo of the internals.

These are the threads I had entered for help:
Fender Red Knob Twin w/GZ34
Fender Red Knob Twin -> 5F6A Conversion
Filter Cap Reduction
Fender Red Knob Tweed Face
Help with Biasing my converted amp

I have been updating the schematic as I go along so I will uploaded it to this thread soon.

Thanks again everyone!

Seth

[CitizenCain]

Very cool conversion! Kudos

[Dagan8]

Thanks for the Kudos. It was a great learning experience.

[Dagan8]

As promised here is the schematic as it is now.



I'm thinking about modifying the 5F6A inputs to just 2 inputs High/Low and adding the second one back onto the AB763 channel. The 2 inputs on the 5F6A channel will be a LOW(single triode) and HIGH(parallel triode) with a single volume instead of normal and bright. I will name the volume as "gain" and put a volume control directly after the 5F6A tone stack instead.

[guitardrdock]

As promised here is the schematic as it is now.



I'm thinking about modifying the 5F6A inputs to just 2 inputs High/Low and adding the second one back onto the AB763 channel. The 2 inputs on the 5F6A channel will be a LOW(single triode) and HIGH(parallel triode) with a single volume instead of normal and bright. I will name the volume as "gain" and put a volume control directly after the 5F6A tone stack instead.

Hey guys - joined this forum as I really want to do the same conversion on my red knob twin, but the schematics seem to be missing - can anyone else post them up for me please?

Thank you in advance.

Phil

[Ptrixx]

Hey guys - joined this forum as I really want to do the same conversion on my red knob twin, but the schematics seem to be missing - can anyone else post them up for me please?

Thank you in advance.

Phil

Bump

[pdf64]

See http://bmamps.com/Schematics/fender/the_twin.pdf
Channel 1 is 'as near as makes (nearly) no difference' to a BF TR reverb channel.