Pedal that de-sustains?

[cheeb]

I'm looking for an effect that would kill all sustain from a guitar signal. I thought about sort of a gate, but I would like for it to fade out "naturally", just prematurely .Even before the strings stop vibrating. I didn't want it to just chop the notes off. 

What about something that shunts the signal to ground automatically, but not immediately...? And the rate at which it does so could be controllable?

I don't know how to even begin designing a "new" effect. Any ideas?

[burnt fingers]

A mis biased fuzz face will gate and cut out.  You could build a fuzz face and replace the biasing resistor on Q2 with a 10 k pot.  I've built a few like this and it goes from nice full woofy fuzz to nasty gated fuzz to psuedo blown speaker to almost no sound at all.

Scott

[Shandy]

I built something called a "Jawari" a while ago, though I don't remember where the layout or schematic came from (I'm sure a quick google will come up with something).  Anyway, it's a kind of sitar emulator, I guess, in that it produces a somewhat irritating distortion and cuts the sustain way, way down.  There might be something you can use there...

[Shandy]

Okay, it's from GGG, but their server is having some issues at the moment...

[CGDARK]

I think that what you want can be achieved with a noise gate type circuit (a good one) with the threshold very high so when you play a note, it will cut the signal as fast as you want. To achieve the smooth transition you must use an LDR or an optofet and some kind of timing circuit at the output of the FWR (full wave rectifier) to obtain the decay that you want. If you need help just let me know. In my years of DIY (more than eleven) I know that I have done this circuit and believe me, it works. Sounds complicated, but it doesn't.

CG

[aron]

I would try a noise gate as well.

[Processaurus]

too bad this Dan Armstrong effect called the "articulator" never saw the light of day.  I would really like to use one.

[Paul Perry (Frostwave)]

The opposite of compression is expansion.
I imagine that any chip with a "downward expansion noise gate" like the SSM2166 from SmallBear could be made to do this.

[DWBH]

You mean like stacatto?

[Mark Hammer]

No real need to go electronic.  Guitar and bass manufacturers have been using foam pads to do this underneath the strings near the bridge for decades.  Since the pad absorbs the energy/momentum of the string, the amount of pressure you apply to the pad against the strings determines the decay rate.  Theoretically, you can get a wide range of decay rates.  Those guitars that had the pad built in normally had a little flip switch to flick the pad away from the strings entirely.  Not quite a stompswitch, but effective nonetheless.

Is this "better" than a pedal?  Good question.  It will certainly perform better than a pedal, because there is absolutely no threshold issue; the damping effect will occur regardless of whether you are ticking the strings or whacking them with a sledge hammer.  There will also be absolutely no lag either, because nothing needs to detect the onset of a strum in order to impose a rapid offset.  That's the perennial problem with envelope-shaping in guitars; you need to detect the onset of a musical event by means of signal strength, while simultaneously rejecting false positives like finger glisses, hum, etc.  Usually this takes a couple of milliseconds.

Is there anything negative about this method?  Yes.  It's always first, and can't be inserted after any other effects.  Bummer.

[birt]

or you can use a slow gear type of effect and mix it with the clean signal in antiphase. then you control the decay instead of the attack.

[markm]

No real need to go electronic.  Guitar and bass manufacturers have been using foam pads to do this underneath the strings near the bridge for decades.  Since the pad absorbs the energy/momentum of the string, the amount of pressure you apply to the pad against the strings determines the decay rate.  Theoretically, you can get a wide range of decay rates.  Those guitars that had the pad built in normally had a little flip switch to flick the pad away from the strings entirely.  Not quite a stompswitch, but effective nonetheless.

Is this "better" than a pedal?  Good question.  It will certainly perform better than a pedal, because there is absolutely no threshold issue; the damping effect will occur regardless of whether you are ticking the strings or whacking them with a sledge hammer.  There will also be absolutely no lag either, because nothing needs to detect the onset of a strum in order to impose a rapid offset.  That's the perennial problem with envelope-shaping in guitars; you need to detect the onset of a musical event by means of signal strength, while simultaneously rejecting false positives like finger glisses, hum, etc.  Usually this takes a couple of milliseconds.

Is there anything negative about this method?  Yes.  It's always first, and can't be inserted after any other effects.  Bummer.

Most of the higher-end Gretsch models came with a string mute.

[magikker]

I'm a sucker for Fender Jaguar's and Jazzmasters, which had string mutes. I think the mutes can be retrofitted on to some other guitars (Tune-O-Matics bridges maybe?), though I've never heard anyone who has. 

[petemoore]

  I remember a 'StingRay' guitar, super full featured, knobs, tremolo, switches, all kinds of gadgetry...and a string muter, a 'see-saw' cantilever with the foam pad on it which is shaped as the fretboard radius.
  Woven yarn between the strings at the bridge, I've seen that before.
 

[Mark Hammer]

Yup.  They show up lotsa places.  Especially the butt of your hand

Without wishing to make too light of the original request, though, is there any special characteristic of sharp decay you are aiming for that is unattainable with the various pad/mute arrangements?  I don't want to paint them as a panacea for everything.  There may well be something you're trying to achieve that still needs "electronic assistance".

[magikker]

I read this the first time and kinda blew it off... But I started thinking about it and I would have some use for this in combination with a passive feedbackloop box. Or with a delay pedal that with a effects loop built into it, so that the effects in the loop just affects the delayed signal... Putting the effect in such a configuration would give you some potentially interesting sounds. 

[GREEN FUZ]

 I remember a 'StingRay' guitar, super full featured, knobs, tremolo, switches, all kinds of gadgetry...and a string muter, a 'see-saw' cantilever with the foam pad on it which is shaped as the fretboard radius.
  Woven yarn between the strings at the bridge, I've seen that before.
 

Teisco Del Rey K2-L,K3-L or K4-L depending on pickup configuration. Beautiful shape, practically unplayable.

[Mark Hammer]

Lest we forget, there is always the E&MM String Damper project that not only does adjustable rise/attack times, à la Slow Gear, but also does adjustable decay times too.

http://hammer.ampage.org/files/StringDamper.PDF

[magikker]

Processaurus, I just listened to the articulator that you posted a link to, and now I want one... How hard would it be for us to come up with a way to build it? It would solve the poster's issue if he just took the modified part of the signal, and the rest of us would have an interesting new box to play with.

[Processaurus]

Lest we forget, there is always the E&MM String Damper project that not only does adjustable rise/attack times, à la Slow Gear, but also does adjustable decay times too.

http://hammer.ampage.org/files/StringDamper.PDF

I was interested and breadboarded that a while back, and wasn't impressed.  Didn't know enough at the time to modify it.  If I remember right the triggering was really bad.

Processaurus, I just listened to the articulator that you posted a link to, and now I want one... How hard would it be for us to come up with a way to build it? It would solve the poster's issue if he just took the modified part of the signal, and the rest of us would have an interesting new box to play with.

I know! It sounds so cool!  There is European patent application with a schematic, but it didn't have values for anything.