Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Hojvaelde on June 26, 2022, 03:49:18 pm
-
Hi everyone here.
After being away from my tube hobby for a few years, now I am back again.
I ran across a bunch of 6JB6A. Some used, some new.
I would like to work a little with these tubes.
Has anyone used them (or similar) in a guitar amp?
-
Hi everyone here.
After being away from my tube hobby for a few years, now I am back again.
I ran across a bunch of 6JB6A. Some used, some new.
I would like to work a little with these tubes.
Has anyone used them (or similar) in a guitar amp?
Never used 'em. But your first stop for the design centre values you'll need is the data sheet. https://frank.pocnet.net/sheets/049/6/6JB6A.pdf
-
it's early and my coffee is HOT, but a snivet?
best I can do is Silly Naval Intelligent - VET :icon_biggrin:
-
snivet?
Haven’t seen one for a few decades
https://worldradiohistory.com/hd2/IDX-Service-&-Sales-IDX/Archive-Service-IDX/IDX/50s/Service-1956-06-OCR-Page-0036.pdf (https://worldradiohistory.com/hd2/IDX-Service-&-Sales-IDX/Archive-Service-IDX/IDX/50s/Service-1956-06-OCR-Page-0036.pdf)
-
I wonder how it can be described as a beam power tube, yet have a 3rd grid (ie rather than beam forming plates)?
-
If colour accuracy is not a concern maybe built a tv? Seriously, get some tubes with a known schematic.
-
Cousin to the 6JM6A & 6JN6 (Compactron versions w/o and w/ plate cap) - Pete Millette built what he called the "Engineer's Amp" - Data on that project here (http://www.pmillett.com/DCPP.htm). Full schema here (http://www.pmillett.com/file_downloads/dcpp_sch.pdf). Copy the output stage and the power supply - Iron is available from Edcor, find that information here (https://edcorusa.com/collections/pete-millett/products/engineers-amplifier).
Basically, 325V B+ with an 8Ka-a reflected load. The power transformer has dual 50V taps that allow use of a FW bias supply, as it's a bit more reliable/safe than the conventional 1/2 wave plans we usually find.
Couple to an AB763 Deluxe or Bassman AA864 or AB165 preamp with the phase inverter, alternatively, if like British tone, couple with the Marshall JBM 800 preamp and phase inverter. If you want to really get extravagant, couple to a Dumble-ish preamp or Soldano SLO preamp.
I have built guitar amps with 7867/6CD6GA and 6JB5/6HE5 with success, ping us if you care to have the schematics/docs to either of those. I took the simplistic path for preamps - 5E3-ish and Matchless Lightning types.
--Pete
-
.