Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Esquirefreak on August 11, 2022, 01:14:38 pm

Title: Differences between Fender 6G16 and 6G9-B
Post by: Esquirefreak on August 11, 2022, 01:14:38 pm
Im currently building a '61 6G15 replica and next build will be a 6G4-A, but one always gotta have a new build in sight, right?

I own a 6G9-B ('63 Tremolux) and its one of the best Fender amps I've heard and played. And by now I've had a few of 'em.

I'm considering building a single channel version using a Bassman size chassis and making a combo cab.

Since I may or may not add reverb it, I thought I'd maybe make it a single (bright) channel 6G16 instead.

Hence my questions:

× Apart from the obvious reverb and a NFB resistor, are there any major differences between the two brownie amps? And yes, I know the PTs are way different with lower voltages in the Tremolux.

× If one included reverb, would there be any pros of following the schematic using a 12AX7 as a reverb driver rather than a 12AT7?

I gotta learn how to keep things short. Sorry about that.

Best regards from the south of Sweden
/Max
Title: Re: Differences between Fender 6G16 and 6G9-B
Post by: EL34 on August 11, 2022, 01:31:32 pm
Best thing do do it for you to print out both layouts and do a compare so you are familiar with both amps
https://el34world.com/charts/Schematics/files/Fender/Fender_Schematics.htm (https://el34world.com/charts/Schematics/files/Fender/Fender_Schematics.htm)


Title: Re: Differences between Fender 6G16 and 6G9-B
Post by: tubeswell on August 11, 2022, 03:52:42 pm
Brown Vibroverb is almost* a BF reverb amp circuit except for the bias-vary trem wiggling the output tubes. Another way of saying it, is the brown vibroverb is like a BF tremolux, but with reverb.


* the 6G16 circuit works better with 12AT7s in the reverb driver and LTP sockets. The 6G16 bias-vary trem has the same hypnotic quality as the tremolux.


Allen Encore is an example of 'single channel BF amp' with reverb and bias-vary trem for 6L6s. Proven design
Title: Re: Differences between Fender 6G16 and 6G9-B
Post by: Esquirefreak on August 12, 2022, 01:30:37 am
Alright!

Yeah, that trem really is something special.

As for the tonestack, how would those tapped treble pots compare to the standard 250k pots of the AB763? I suspect it will affect both highs and higher mids?

/Max