Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Misc Schematics and Layouts => Topic started by: tubeswell on December 18, 2010, 05:45:53 pm

Title: Schem for tweed bassman with verb and trem (homebrew)
Post by: tubeswell on December 18, 2010, 05:45:53 pm

Here is one of my amps that resulted from various attempts to get verb and trem into a 5F6A circuit. I have dubbed this the '5F6B+'

A bit of guff about the circuit - the trem utilises an AC-coupled CF stage (started out with a 6G16 circuit, then went to a 6G9B and finally settled on the AC-coupled CF after much experimentation with different ways of getting good slam but keeping the heater-to-cathode voltage reasonable) . The verb was derived (copied) from the Allen Old Flame in the end taken between the tone stack and the PI. The first stages got paralleled grids with the triodes mixing back into the DC-coupled pair its much easier to blend the channels at will that way (it is noticeably louder with both channel volumes turned up).

There is an .mp3 on this link - both channel vols on about '2.5', (on lead track - Dwell on 9, verb level on 6, verb tone on 6), treb on 6, mid on 4, bass on 1, speed and depth on about 2-3) Mic'd with SM57 through my desk into garbage band on my mac. At the end I played with the trem depth and speed for a few strums on the lead channel. This amp still has the 2 x greenback G12M 12" (25W). Powered by 2 x Russkie 6P3Se idling at 13.6W. Through my strat on neck 'pup with everything dimed.

http://music-electronics-forum.com/attachments/12048d1292712883-mystery-man.mp3

Title: Re: Schem for tweed bassman with verb and trem (homebrew)
Post by: tubenit on December 19, 2010, 06:49:08 am

That sounds pretty cool!  I like it.

For some reason, I could not open the J-schem file. Tried it twice. 1st time it part way opened & second time nothing opened?   

Any chance that you could post a GIF or bitmap of the schematic?  I'd really like to see what you did.

Thanks, Tubenit

Title: Re: Schem for tweed bassman with verb and trem (homebrew)
Post by: tubeswell on December 19, 2010, 11:57:33 am

There you go

(PS I just realised this needs updating -  don't look too closely at the voltages  - I recorded then at different times in different incarnations with different power tubes in (so the RT B+ and the LFO B+ should both be the same as the Scr B+ etc)

Title: Re: Schem for tweed bassman with verb and trem (homebrew)
Post by: tubenit on December 20, 2010, 07:42:13 am

Thanks for sharing that!  Very nicely designed and thought thru. I'm impressed. Job well done.

With respect, Tubenit