Sunday, October 5, 2014

Why the heck would I NOT want to build this???

I love the clean sound from my Simple Preamp/20Watt Push-Pull amplifier that I built...

I love the "classic rock" crunch of my Lite IIb that I built...

So... why in the heck would I NOT want to build them BOTH into the SAME AMP so I would not have to lug two amps and two speaker cabinets around and subject my soundman to miking-up two cabinets???

I am discussing this design at here.

Crude block diagram...

I would love to hear your comments in the discussion at or leave a comment here!!!

One thing I need to work out is how to get them both going at the same time and still include the reverb/effects. I don't think it's as simple as just replacing the 3PDT with a 3P3T switch, but it's getting late and I need to think on it later...

After some discussion, here is version 0.1a...

Saturday, October 4, 2014

Marshall 18 Watt build

...Placeholder for my 18Watt build...

Over at, there are a few designs of the old Marshall 18watters they put out in the 1960's. These things sound pretty freakishly amazing, as does mine.

I built the "Lite IIb" version with tube rectification and a VVR (variable voltage regulation) unit that I originally bought for my TC15 (see post below) but I never installed it in that amp.

This amp sounds absolutely fantastic and it really nails that early Marshall crunch sound. Does that "classic rock" sound REALLY well.

Uses a pair of EL84 output tubes and Classic Tone power and output transformers.

More to come......

The "Simple20"

...Placeholder for my third amp build...

The pre-amp is the Simple Preamp from and the power amp section is the 20 watt push-pull also from

This amp sounds amazing! Really nails that "Fender Clean" and overdrive - think Deluxe Reverb.

I used JJ 6V6 output tubes and Edcor power and output transformers.

This is my "main amp" that I use on-stage with Sonhouse Blues Band.

More to come.......

Monday, June 9, 2014

A Very Flexible 2x12 Speaker Cabinet

Schematic for how to wire a 2x12 cabinet so that it will run with these options:

  • Use either jack - Mono, 4-ohm load
  • Use both jacks - Stereo, 8-ohm load
  • Use both jacks - Two amp heads, each powering its own speaker (1x12)

Of course, this assumes you are using two 8-ohm speakers. Do the math if you aren't.

I mean, if you were going to make a 2x12 cabinet, why WOULDN'T you wire it this way? It uses standard Cliff-type jacks which are cheap. Real Cliff jacks are actually cheaper than a Switchcraft and give you so much more flexibility.


Saturday, May 31, 2014

Other Guitar-related Electronics Projects I've Done

Eventually, maybe I'll do a post about these projects:

1) A TS-808 (Tube Screamer pedal) clone I built. Sounds pretty good. I've actually used it live in front of my Peavey Classic 30 with good results.

2) My A/B/Y footswitch with tuner bypass mode and 4 LED status indicators. Does an awesome job of adding channel-switching and channel-jumping to my Trinity TC15 amp I built from their kit ( It also has a "tuner/bypass" mode with an output jack to feed a pedal tuner - also works great as a mute switch. The LEDs are indicators as to what routing mode the pedal is currently in. Channel A & B LEDs are obvious. Instead of lighting both in Y mode, the Y LED lights when it is in Y mode, but the A or B light is also still lit in this mode to indicate what channel it will return to when the Y mode is deactivated. I included a 555 chip to flash the bypass mode LED - basically an idiot light to remind me why the guitar isn't making any noise. The A/B/Y lights also are still indicating their current mode while in bypass mode so I will know what mode I am in after I turn off the bypass. I can also mute, switch to another routing mode, then unmute. VERY flexible and well worth the time and expense!!! Way cheaper and more features than your typical passive ABY footswitch available today too! This was a very easy build and except maybe for the 555 IC flashing LED circuit, this could easily be a "first build" for someone new to electronics.

3) A reverb pedal using the "Belton brick." I am actually extremely pleased with how this thing sounds. I used the mediuim-decay model brick. Google "Box of Hall with dwell" for the design I based mine on. No pic of the outside yet. Nothing to see really, just three knobs, a stomp switch and an LED. No labels or anything yet. Of course I am still working on perfecting my stand-alone tube reverb unit, but this will tie me over until I get that working and in a proper cabinet. It will also be a quick-and-dirty reverb for when I don't want to lug the stand-alone out to a gig for whatever reason.

Designing an all-tube push pull stand-alone reverb unit

I finally fulfilled a long-time dream of mine and I built my own all-tube guitar amp. It is a 15-watt clone of a Matchless HC-30. The kit was purchased from Trinity Amps. It sounds phenomenal. It does not have any reverb though, so I set out to build a stand-alone reverb unit. I did not want to do the obligatory Fender 6G15 for no other reason than just to be different.

After a lot of research, I made this design based on the Firefly by Doug H. (see and the stand-alone reverb design in Kevin O'Connor's book "Tonnes of Tone" (see

Version 1.0:

Wasn't quite "there." After my initial observations and some feedback from the fine folks at and Trinity Amps ( - you MUST check them out if you are at all interested in building your own tube guitar amp from a kit) I made some changes and improved things.

Version 1.1:

This brightened it up a bit and took care of some nasty red-plating of the 12AT7. Sounds a lot better and the tube no longer burns my fingers to the touch. I still think it could be better though. I am still experiencing some hum - probably because of my inexperience with layout. You can post comments here if you have ideas for improvement,  or over on the forums at and I have some threads where we are discussing this.

Next thing I will probably try is changing the cathode resistor from 1k5 to 1K.

The unit on my workbench:

The unit on top of my TC15 build and my TS-808 clone I built: