AX84 October Tube Guitar Amplifier Project
[classic projects]
[current version] [testing version] [old
versions]
Overview
The October series are all push-pull guitar amp that use a variety
of tubes for different amounts of output power. The Studio
version uses a 6SN7GTB dual triode and has an output power of 2
watts. The Club version uses a pair of 6V6 beam pentodes and has
an output power of 20 watts. The Stage version uses a pair of
beam tetrodes and produces 50 watts of power. The Stage version's
output power can be reduced by using KT66's or 6V6's instead of the
KT77's.
The preamp has two seperate bright and dark channels that can be mixed,
via individual volume controls, for a wide range of tones.
Additionally, the two preamp channel's character can be changed via a
switch, from a late 60's - early 70's "looser and smoother" sound to a
late 70's - early 80's "brighter and tighter" sound.
The October has a traditional "TMB" tone stack and a pre-PI
master volume control so that the user can control the overall output
of the preamp signal.
The power tubes have individual bias pots to allow tube sets to
be used longer. Folks that like the sound of a little mis-match between
power tubes can dial in the exact amount they want. The October also
includes external test ports and bias pots so that the bias can be
checked, and adjusted, without opening the amp.
By far, credit for the best description of the October must go to
Jon Anderson:
It's got 3-4 decades worth of tones in
it. I just recently added my 'Bassman Mod' to mine. Basically a pot on
the NFB so it ranges from JTM45 style NFB to a more subtle Bassman
amount.
- 1950s: '59 Bassman : Hook up some alnico/jensen speakers to it,
crank down the NFB, flip switch to 'Plexi', and plug in a Tele. Start
your chicken pickin'
- 1960s: Crank up the NFB, leave the switch, plug in some
greenbacks. Maybe add a RangeMaster, plugging into the Normal Channel.
Grab your 1960 Les Paul Gold Top with PAFs and start playing
'Hideaway'.
- 1970s: Flip the switch to 'Ali'. Crank everything up to 6-8, back
off the NFB to about 5, hook up some G12H30's, and start playing 'All
Right Now' with your LP.
- 1980s: Grab your super strat, EQ and Delay pedals, crank it up to
10 all around. Probably need a bit of a boost in front as well, but
becareful it doesn't start an Eruption.
Features
- Seperate, bright and dark preamp stages.
- Modern/Vintage preamp voicing switch.
- Variable NFB control.
- Individual power tube bias controls.
- Bass, Mid and Treble tone controls.
Skill Level: advanced
--- Status: Ready to Build.
Before using these materials, please read our terms and conditions.
October ~ Studio Current Materials
Older Versions:
| 08.08.03
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.08.03 version of the AX84 October ~ Studio.
|
| 08.06.25
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.06.25 version of the AX84 October ~ Studio.
|
| 08.06.01
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.06.01 version of the AX84 October ~ Studio.
|
| 08.05.21
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.05.21 version of the AX84 October ~ Studio.
|
| 08.05.19
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.05.19 version of the AX84 October ~ Studio.
|
| 08.05.07
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.04.25 version of the AX84 October ~ Studio.
|
| 08.04.25
October ~ Studio |
Schematic, notes, bill of materials, board template and
chassis
layout for the
08.04.25 version of the AX84 October ~ Studio.
|
Older Versions:
| 08.06.16
October ~ Club |
Schematic, bill of materials, board template and
chassis
layout for the
08.06.16 version of the AX84 October ~ Club. |
| 08.06.08
October ~ Club |
Schematic, bill of materials, board template and
chassis
layout for the
08.06.08 version of the AX84 October ~ Club. |
| 08.06.05
October ~ Club |
Schematic, bill of materials, board template and
chassis
layout for the
08.06.05 version of the AX84 October ~ Club. |
| 08.05.12
October ~ Club |
Schematic, bill of materials, board template and
chassis
layout for the
08.05.12 version of the AX84 October ~ Club. |
| 07.10.04
October Club |
Schematic, notes, BOM, board template, chassis layout, and
template for the
07.10.04 version of the AX84 October (note that at the time these
documents were done there was only one October project, not three, so
the documents are just labled "October" and not "October ~ Club"). |
07.10.04 October ~ Club
Build Guide
|
This is a build guide showing
the construction of the October ~ Club prototype many moons ago.
|
October Club Sound Clip
|
AVI file of the October ~ Club
featuring guitar virtuoso Chris Hurley.
|
Is this area looking a little skimpy? Looking for older materials
and
soundclips from previous version? Check out [the
older versions]
Before using these materials, please read our terms and conditions.