18w Stout & Plexi designs

[tubenit]

There is a thread on this with some GIF schematics here:  http://el34world.com/Forum/index.php?topic=17583.0

What I thought I would do is offer some more designs with the goal that:3)  will use the Hoffman style 18w layout board

1)  will work with the (18w/5E3) chassis
2)  will use the Hoffman 18w PT & OT

So, I offer the following ideas that should work with chassis, trannies and layout board!  All are DRAFTS.  I have NOT built any of these.

CHECK for errors!  Compare schematics to one another.  Compare schematics to the Hoffman layout.  Post any concerns or questions

18w Stout schem variations has the following schematics & will work with Doug's PT & OT, chassis and Hoffman 18w layout board:

- 18w Stout original
- 18w Stout & VVR
-   9w Stout   (6BM8)

IF for some reason, you feel a need to lower the B+ volts on power tubes plates, you can consider the zener diode trick, VVR and other options such as listed here:  http://el34world.com/Forum/index.php?topic=17595.0    Having said that, I am anticipating maybe 320v or so using a 5Y3GT?

NOTE:  these schematics should work well with Doug's original Hoffman style turret board:
http://el34world.com/Hoffman/files/Hoffman_Stout.pdf

With respect, Tubenit

[tubenit]

Two more ideas that I think will work great with Doug's trannies and chassis!  You'd use a 8pin hole to 9 pin hole adapter on one of the 8 pin holes, so you could have a 3rd 12A_7 tube.   The 6V6's would be in one of the 6V6 holes and in what original was to be the rectifier tube hole. You'd just use a solid state rectifier.

The Carolina Blues Special is still one of my favorite amps.  My best friend and my son in law both have one.  It's like a 5E3 tone but cleaner and with reverb.  I played this with HotBluePlates when HBP brought his 5E3 to my house. Similar tone, cleaner and verb. I built two CBS amps out of Bogen DB-110 chassis, so I am confidant you could put this in the chassis that Doug is getting.

The Tweed BluezMeister clean has a beautiful tone, IMO.  I think Doug's chassis might not have room for relay switching, but you could sure use mini-toggle DPDT to have the mid-boost (very useful with strat pickups) and the PAB (preamp boost).  Engaging the midboost and the PAB really does increase the sustain on the clean channel.  One of my favorite blues tones is the clean on the TBM with those engaged.

CHECK for errors!  IF there is a discrepancy between the schematic and layout, go with the schematic.

NOTE:  Doug's tagboards are 28 tags per 11.8".     20 tags would be 8.42"     16 tags would be 6.74"

One could make a paralleled turret board shorter in length. OR make a two section layout board ( preamp - LTPI)

With respect, Tubenit

[tubenit]

I realized using the triode/pentode of the 6BM8, that one could build a HoSo56 (Geezer's design) using a 5879 V1.
This is a very very touch sensitive great sounding amp, IMO.

This would be a GREAT amp to build in this lunchbox chassis! 

IF anyone has a concern about the B+ of around 320v being too high on their 6BM8 pentode plates, you can use the "zener diode trick", a VVR or the mosfet follies  B+ reduction idea here:
http://el34world.com/Forum/index.php?topic=17595.0

CHECK for errors!  IF there is a discrepancy between the schematic and layout, go with the schematic.

NOTE: I added a short layout board in case someone prefers that.

          Doug's tagboards are 28 tags per 11.8".     20 tags would be 8.42"     16 tags would be 6.74"

With respect, Tubenit

[tubenit]

These are 5E3/18w hybrids.  They have the preamp stage of a 5E3 & the 18w LTPI into either 6V6 or 6AQ5 power tubes.

All the schematics are in one SCH format, there are multiple pages with different schematics.

CHECK for errors!  Compare schematic with layout.  IF there is a discrepancy, then go with the schematic.

These will use Doug's 18w chassis, 18w PT & OT and then either a tagboard or a paralleled turret board.

With respect, Tubenit

[tubenit]

These are 18w Plexi ideas.  All the schematics are in one SCH format, there are multiple pages with different schematics.

CHECK for errors!  Compare schematic with layout.  IF there is a discrepancy then go with the schematic.

- 18w Plexi   (EL84)
- 9w  Plexi & VVR  (6BM8)

With respect, Tubenit


NOTE:   the 9w Plexi & VVR layout can be very easily edited in minutes for an 18w Plexi 6V6 & FX version
         & the  18w Plexi version (with EL84's) can be very easily edited in minutes for an 18w 6V6 version  (without FX)

NOTE:  Doug's tagboards are 28 tags per 11.8".     20 tags would be 8.42"     16 tags would be 6.74"
One could make a paralleled turret board shorter in length. OR make a two section layout board ( preamp - LTPI)
           

[tubenit]

Tweed BluezMeister clean Reverb would use a tagboard or a paralleled turret board that should be about 7.58".

You would need to use an adaptor on one of the 8 pin holes to have another 12AX7.  And you would use a solid state rectifier for about
420v on the plates of the 6V6's.

You'd use a terminal strip for the reverb 150k mixing resistor.

You would use a mini-potentiometer for the dwell on the back of the chassis.  Use Doug's Fender replacement reverb trannie and tank.

I have built a reverb 6V6 amp into a Bogen DB-110 into a 12" chassis, so I am confident this could be done with Doug's chassis. The Bogen had 3 12AX7's, two 6V6 tubes and a 5Y3GT. It was a quiet amp.

I think this would be a VERY nice blues amp with the added reverb!  I have built something similar to this already and liked it a lot.

CHECK for errors!    Compare schematic with layout.  IF there is a discrepancy then go with the schematic.

With respect, Tubenit

[tubenit]

The Tweed Overdrive Special is a great amp with very nice tone.  I think this Tweed Overdrive Special Jr.  would be an excellent amp for those of you who like a smooth overdriven tone.

I would probably build it with a 12AY7 in V1 and the 5751 in V2 and a 12AX7 in V3.  I think with that combination, one might end up playing it with the OD engaged 90% of the time. 

CHECK for errors!  Compare schematic with layout. IF there is a discrepancy, then go with the schematic.

NOTE:  I added a 5879 OD version also, but don't have a layout. One can easily mod the existing SCH layout to fit. IF you need help drawing a layout for this, then PM me.

With respect, Tubenit