Bend Tendencies

[goldenbaby]

I've been finding a few glitching bends and ones that create all-new steady tones, but not yet any pitch-bends.  I've been interested in know a little bit about patterns, for example:

Where do good body contacts usually come off of?  The only one I saw the wiring diagram came off the end of a capacitor.  Is this typical?

Other than resistors and chips, what are good components to aim at?

[computer at sea]

I usually start with chips and then take a look at resistors.  If you have (or make) a resistor substitution box it's pretty easy to try a bunch of different values.  Another thing I do is disconnect any trim pots, measure them, then add much bigger pots in.  Sometimes it works, sometimes it doesn't. 

I don't tend to fool around with capacitors too much, as of yet.

[hoffy]

Gazalla's book says you should lick your finger, then touch the resistors on the board to find the pitch bends... I usually stumble into pitch bends without doing that. I'd recommend not having your gear connected to mains power if you're going to try his method.

[goldenbaby]

I've done the lick the finger method, found some small bends.  I would never do it with mains no matter what method I was using for finding bends.

[Gleix]

What they said. Touching the board with your finger, or holding onto something metal (like the end of an alligator clip while probing with the other end) is a great way to find a pitch bend.  Along with what computer at sea said (removing trimmers) it's also possible to, if a resistor is what keeps the pitch where it is, simply remove the resistor and replace that with a potentiometer.  It's always good to try different values, as some values will be to large and cause "dead space" when in some positions.

It's a good idea to keep a good stock of different sized pots around.  I keep plenty of 1M, 500K, 100K, and a bunch of lesser values ranging from 1K to 10K. With those (and a little selection of trimmers and resistors) it's always easy to find the perfect value for whatever bend you need. 

[computer at sea]

Having a good assortment of potentiometers really makes a big difference.  I went to the 2007 BENT festival and was asking Pete Edwards from Casper Electronics for advice on what parts made the most sense to have on hand and he suggested filling up a drawer with pots. 

[Circuitbenders]

and yet inevitably the one you need will be a 22K log pot or something stupid like that that nobody in their right mind would actually have.

[computer at sea]

And eventually you'll just have the lousy ones left.  I have a heap of 250k pots that click when you turn them.

[Gleix]

and yet inevitably the one you need will be a 22K log pot or something stupid like that that nobody in their right mind would actually have.

That's where a nice selection of resistors and trimmers come in!

[goldenbaby]

What's the diff between a pot and a trimmer?

[Circuitbenders]

Trimmers are the little pots sometimes called presets you get on circuitboards that are usually set with a small screwdriver and then left, they can sometimes be removed and brought out to a front panel as proper knobs.

Pots are Potentiometers, i.e. the big ones you use as control knobs