The smaller satellite board on the right contains the optocoupler and related circuitry which attaches to the XLR jack.   This isolates the footpedal from the rest of the audio circuit – no audio travels through the expression pedal cable.  The rest of the wiring goes pretty fast, too:

Here is a closeup of the V847 Wah board:

I modded it with a couple of trimpots to control the “Q” factor and the gain on Q1.  I also switched out the inductor for an old Crybaby inductor, as I preferred the sound on it.

The front jacks are normalled to the rear jacks, so if nothing is inserted in the front, the signal will pass through to the rear jacks:

Now we are ready to rock…

I don’t have an fancy milling or machining tools, so I printed out some full sized patterns from the drawing, and used them to mark the front (and back panels) for drilling with a drill press.

The labels were made using a P-Touch printer.

So it’s a relatively simple matter to disconnect the pot from the circuit and implement the alternate circuit using a 3 conductor cable (XLR or TRS) and an expression pedal. I use the Boss FV300L since I have one sitting around (and b/c Edge has one too of course…) In place of the LED/LDR pair R.G. describes, I think it’s easier just to use an off-the-shelf NSL-32 optocoupler.

The first step was to build a very rough prototype with some spare jacks and scrap sheet metal parts, to make sure the concept would work. I usually do this for pedal experiments:

Edge’s rack wah is a Vox V847 but I happened to have an old Crybaby board lying around, so I used that instead. The circuits are virtually identical. Next was to attach the FV300L with a mic cable give the wah a test drive. (Note: This also required a cable splitter from TRS to two mono cables) Here I used it for a cover of “The Fly”:

Once I was confident the prototype worked as I hoped, it was time to design a nice box for it…

The Classic Era: 1984 to 1990

The Awesome 1990′s

2000′s U2

This is a new section of the site I’m working on, which is very much inspired by the website gilmourish.com (which I am a big fan of).

I’ll be adding settings, tips, and other suggestions that I think will be helpful in trying to duplicate Edge’s tones with your own setup.

You’ll be able to click on the album thumbnails and this will take you to a page listing songs and suggested effects settings.

(Yes, I am biased in favor or 1990′s U2… That should be obvious. )

Thanks for voting!

Dave

http://www.effectsdatabase.com/model/dtsaudio/sdd3kp

They have even archived pics of Version 1 and Version 2.

Also, as an experiment, I’m trying out the use of Paypal buttons to see if this makes things more convenient for everybody who wants to place a reservation.

Deposit to Reserve an FA-2 pedal without Footswitch (Traditional Style):

Deposit to Reserve an FA-2 pedal with added Footswitch:

Bear with me as this is very much in “beta” mode. However, if this works out well for people, I may set up a separate web shop in the future for those who want to purchase pedals.

Thanks!
Dave

http://www.musette-japan.com/

http://rush.sub.jp/musette/archives/gear/dts/index.html

Dave

A good way eliminate this problem and to make the A3 more rugged is to replace those Jalco Jacks with something you can mount to the rear panel using a nut, and then connect wires to the circuit board.  This way there is no more stress on the circuit board from the weight of a heavy 1/4″ phono plug.  The space to do this in is not very big, however.  The most convenient jacks I’ve found for this (so far) are the Neutrik Slim Jacks.

They are made for PCB mounting applications, but that’s OK.  The soldering pins are big enough for you to solder a wire to.

Here’s a friend’s A3 I did some work on, with the original Jalco jacks visible:

The next step is to carefully desolder them.  I use desoldering pump to do this and its has been a problem.  Sometimes it helps to add fresh solder (with its flux) when desoldering old solder.  Here’s the board with the jacks removed:

Now one can position the news jacks to see how they will fit:

As you can see it will be a tight fit next to those inductors/ ferrite beads.  One of them has to be turned on it’s side. Because of space constraints,  I’m not going to replace the “Direct Out” jack (it’s rather useless).

Now solder some wires to the jacks. I’m using 22AWG wire here:

Then solder the wires to the board:

To keep it simple, the ground wiring (black wire) is only connected to the board in one place.

Here are the old leftover jacks after being removed (By the way if you need to buy these, you can get them at Mouser.com. They are part number 16PJ500 or 16PJ509 under the brand name Kobiconn):

Finally, here’s a view of the back after everything is put back in it’s place. Don’t worry about the open hole – there’s an easy fix for that…

You can get little plastic plugs at the hardware store which will pop into place and fill the empty hole in the rear panel.  ( It would have been better if I had found a black one, but it’s only going to be at the back of the rack…):

Now this A3 is going back home, and hopefully it’s wild flanger sounds will make it’s owner comfortably “Numb” for many more years to come…