Messages

Brian, got any teasers for the Fat Pants Jr?

I've started getting into 1590a builds and like everyone says, thems is addictive!

It will be stripped down--just a volume knob and boost switch and no input buffer..for 1590A specifically. Same basic sound with less options.

They will be up later this afternoon.

Yeah it went live about 5 min. ago.

Socket R31 and raise the value until it oscillates at the point of your choice on the pot rotation.

Yup. Try 33k, 47k and 56k.

What's the Kraken?

It's the Mutron Micro V I've been working on.

Shipped! The sale and new boards will be available on the Projects Page tomorrow. Today I want to finish the two remaining docs (FatPants and Sparkplug). I'll have the PCBs on-hand by Friday.

Demos to be done: Harbinger, new Sparkplug, ZPDX. I probably will not demo the new FatPants since it is mostly identical in tone to the previous version.

Stage Fright and older FatPants demos are here:
http://www.youtube.com/watch?v=nZwEXghYrp8
http://www.youtube.com/watch?v=mdC-9HL83hc

Two of these with a parallel/series switch would be really interesting running to a stereo amp setup.

Yeah, mine actually came on Saturday. I had some good fun with it....so simple.

12v is actually a very good spot for the bias on the JFET. What you have is fine. You could get it further down by increasing the value of the trimpot or the resistor that is attached to it.

Sure. Just use it as a DPDT for something! Or, use it as a 3PDT but with a different wiring schem that does not need that lug. Basic bypass with LED can be done with it.

I got a weener wah as a runner up prize in last month contest.  This is great because I need to build a wah... my last attempt was a failed mod wah build.

I want to get an opinion on caps for the weener wah.

It looks like you have the option for radial caps, but is this really just for mojo?  Not sure where to source these, but the link to the 4uf one was like $4.00 for one cap... thats a bit scary, since I need 9 different caps... I guess I could spend $40 on caps, but it really better sound better.

If not radial what should I use?  Film, polystyrene ... any suggestions?

I also have red fasel and a sabbadius soul inductor that I can salvage from a failed mod wah build.   Will the soul fit?  It is 500mh, is that a good value with the stock values on the build doc?  I'm not sure where to source a whipple?

If anyone has a reliable source where I can get a set of radial/mojo caps please let me know, I just don't want to spend $30 on shipping from a half dozen ebay sellers on $3.00 caps if I can find a more efficient way to do this.

The option is for axial caps (radials are the ones we normally use, like film/box/etc) and are purely for the mojo factor. I tend to stay away from proclamations about which one or what type is better. But, since there was enough space on the board I included options for both types. I've used axials/Orange Drops on my builds because I happen to have the correct values.

If you want to spend the money and want the mojo factor, use axial caps and carbon comp resistors. But, that is a pretty expensive build. Otherwise, carbon/metal resistors and  caps will be just fine, and are what you find in most commercial pedals anyway, like the Dunlop/Vox ones.

I don't really have a suggestion for axials caps, since most of mine were bought from an old electronics store back in Austin...all NOS stuff. But, you can use the spacings listed as a guide for finding the right size. Maybe someone else has a good suggestion.

A 500mh inductor is just fine. Easy way to test if it will fit is measure the pin spacing on it and compare with those on the Weener. The Weener has several pin spacing to accommodate as many inductors as possible. The Whipple can be found on ebay, last I checked. The guy who makes them sells them there.

What is the optimum voltage of pin 8 on both the MN3101 and MN3005? (they are tied together) And what is the purpose of the 1n4148 diode (or similar) on pin 1 of the MN3101?

With the MN3101/MN3005 pin8 can either go to ground or left filtered by electrolytic cap. I've seen it both ways, so either is fine AFAIK. If you are reading a high voltage there, I suspect some kind of mistake somewhere...it should be close to 0v. However, on a 3205 type build, pin8 should be 14/15 of the Vdd voltage.

If you see a diode on pin1 of the MN3101, it's likely to drop the supply voltage a bit so it is slightly different than the audio supply voltage. There are different ways to handle it. The ABDX does it with a small resistor. In the same way, the ABDX uses a diode to drop pin8 down to the approximate Vgg voltage when doing a MN3101 and MN3205 combo.

This will make all those husky Alpha pots like gold: hit the inside with contact cleaner and rotate it back and forth about 25 times. It will loosen up a whole bunch.

Could be just too much gain causing some oscillation. It might get more prominent with the mid range boost on. Try cutting R5 down to 470k - 680k and see if that stops it.

Cool. They must have gotten one of those UV printers. Good news!