"Bow" effect.

[sevenisthenumber]

Korg has a "Bow" effect in their Pandora's Box. If you haven't heard this effect, it is simply a constant sustain, with seemingly endless controllable feedback, and it never stops until you do, or if you turn the unit off.

Much like an ebow but its a pedal that does it. I also know of the Boss DF-2 but thats not it either.....

Anyone know of a build for something like this?

[runmikeyrun]

put your headstock on the speaker cabinet.  No batteries, no expense, and works every time 

I think someone made something called the sustaniac?  That was a pickup type thing that you installed in your guitar.  Maybe try to look one of those up.  I think there was a discussion thread on here once about wiring a pickup to work as an ebow type sustainer.  Also sustainiac made the Model C which was a stompbox connected to a box you clamped on the headstock, which vibrated the strings.  In other words, a fancy way of accomplishing what my first statement accomplishes.

Maybe you could use some sort of a feedback loop on a normal clean boost... a pot to adjust how much of the original signal to feed back on to the booster's input?   

[Ripthorn]

If you go to projectguitar.com, there is a thread that is about 300 pages long devoted to building this into a guitar as an onboard thing.  It is simple and works quite well from what I hear.  As far as a pedal, it would just take what can easily be put in a guitar, adding more cable and an enclosure.  Check it out, Pete there knows everything about this.  All the issues and benefits are constantly being discussed there.

[Lurco]

http://www.diystompboxes.com/smfforum/index.php?action=profile;u=2800;sa=showPosts

[ayayay!]

What about the Fernandes Sustainer? 

[Lurco]

What about the Fernandes Sustainer? 

dunno, tell us more!

[Zen]

What about the Fernandes Sustainer? 

that was my first though -- but their system is not, well, it is, um well...here:

How does it work?
The patented FERNANDES SUSTAINER system generates a magnetic field causing the strings of the guitar to vibrate. Powered by a 9-Volt battery, the interaction of the bridge humbucking pickup(B), the Sustainer Circuit Board(C) and the neck Sustainer Driver pickup(A), projects magnetic pulses that continuously vibrate the strings of the guitar, the same way an amplifier at extreme volume would do, yet totally controlled! The result is infinite sustain and/or feedback using sparkly clean or loud distorted settings without the need for excessive volume or extra outboard gear!

http://www.fernandesguitars.com/howit.html

[sevenisthenumber]

i know about the sustainer. Im thinking pedal format. I just havent seen it done really....

[Ripthorn]

The way I see it, you only really have two general ways of doing it.  You can use some sort of digital sample and hold (kind of like an infinitely long delay that starts immediately) or you feed back either vibration or a magnetic signal to induce sympathetic vibrations back into the string.  If you do the first, pedal form is no problem, if you do the second, then putting it into pedal form would make engaging the circuit easier, but you would have to use it with a guitar that has a driver already in it (unless you use a driver mounted on your picking hand, like the infinite guitar system that the Edge uses).  The only problem with a hand mounted driver is getting the right spacing and the fact that it would be really difficult to play sustained passages.  Just some thoughts.