I traded a Fuzz Factory Clone for what looks like an old PA that’s been modified to work as a guitar amp. The Webcor has two speaker connected with what looks like a giant oil and paper capacitor. One speaker looks to be about 6 inches across and the other is about 4 inches.

There are four tubes: 12ax7, two 12ab5 and a 5y3-gt rectifier. I’m not the tube expert, but it looks like the 12ax7 is used as an input preamp. The two 12ab5 tubes are set up in a push pull configuration.From what I’ve read it sounds like the two 12ab5s put out about 9w max. The amp is pretty quiet, good for mellow practice.

Here’s a few pictures.

Here’s a picture of an Ugly Face I made recently. For the graphics on this I used PnP. Not sure how this is going to work out. This is second effect I did with this method. This one came out better than the fist.

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This will be the fourth time I try to build one of these. I made a PCB for the original using the layout from GGG. I never finished this. Then I built and finished a second using the layout from UStomp.com. I couldn’t get this to work. I forget what the problems were, it was more than a few years ago. Franciso Pena, of Tonepad.com came up with a new and improved version that used 13600 in place of the 3080s. I built the first version of this. It was the most successful of the bunch. It worked pretty well but had two problems that I couldn’t seem to solve. With mine you could hear a ticking from the sample rate oscillator and the sweep switch refused to work in one direction.

Anyway, I found a sheet of PnP that I had printed sometime ago of Francisco’s second version of the FSH-1. I thought what the heck, might as well give it another try.

Here’s my take on the Ugly Face/Crash Sync. I took my favorite parts of both and a few suggestions from RunOffGroove and the DIYStompboxes forum.

This version uses a different input buffer, which more closely resembles the input of the Crash Sync. Though it has a greater gain. I found this gave more sustain. The Ugly Face has a gain of about 200. The Revolting Visage uses a gain of about 1000.

I took the envelope from the Ugly Face which is simple and elegant and seems to work well for this design.

I also borrowed the Threshold from the Ugly Face. Which allows for self Oscillation.

These last two features do not exist on the Crash Sync. But, are a lot of fun to play with.

I changed the output to be directly taken from pin 3 of the 7555. The Ugly Face used a strange arrangement that was also connected to pin 7. The pin 3 arrangement makes more sense to me and is simpler.

I like the Tim Escobedo’s Ugly Face I’ve built about 7 now. This is a really fun pedal. Total Sonic Mayhem. Not for Jazz, though I’m hoping someone will take that as a challenge…

Something that is not really a problem, but has always bothered me is the volume. The Ugly Face is extremely loud. The output swings about 0 to 9V. Which leaves a small usable range on the volume knob.

Lately I have been adding a 68K resistor in series between the volume pot and the output from the circuit. My measurements seemed to suggest an 80K would be better but I had 68K on hand. The the thing is still way loud. But now at least volume pot seems to have a more usable range.

Here’s a sound sample of the 9V Sample & Hold I have been working on. So far things are going pretty well. It’s based on an idea by Brian Marshall and the Color Sound Wah.

9V S&H Test Mp3

I have this for Sample and Hold effects. Though I have yet to build a really good one.

Here are a bunch of sketches of S&H ideas that I have been testing.

This is the Maestro FSH-1.

This uses a 7555 timer for a clock in an attempt to get as short and sharp a clock pulse as possible.

This is Ray Wilsons Sample and Hold from Musicfromouterspace.com

Here’s an idea from the app notes of the 13600. This one worked pretty well.

This idea came from the Diystompbox.com forum

Don’t miss the Musicians and DIY Electronics swap meet at 924 Gilman Street in Berkeley. I had a great time last year and the Year before. Lots of good deals to be had. Last year there was a ton of analog synth equipment and the year before there was a group with a massive amount of old military tube electronics. Last year I sold a few boxes and some PCBs. I picked up some pretty cool books, The Active Filter Cookbook and the Craig Anderton classic Electronic Projects for Musicians. Which I bought when I was about 16 but could never figure it out. Here I am 25 years buying it again.

I have been getting a lot requests for a drilling template. So here it is at long last. This drilling template may not be super accurate. Be sure to drill the initial holes a little smaller and check alignment against your PCB before opening the holes. I use a round file and a hand reamer to make adjustments.

1590 B Drilling Template

Here’s a simple mod that adds a blend pot to the Ugly Face.