Keyed gate query

[niftyprose]

Hi guys, I searched before posting this topic. It seems to come up every few years.

I want a keyed gate pedal. I think it will be a four-jack box. The objective is to connect guitar and amp to 'In' and 'Out' jacks, and to put a delay pedal into the Send and Return jacks of the f/x loop. I'd like to be able to trigger echoes by hitting a chord hard but otherwise get a dry sound. (Same as the Pladask Gjengangar.)

AFAICT, I can do this with the DOD FX30B and maybe some other peds. However, there isn't a dedicated unit. Can anyone point me at resources that would hlep me?

Best, W.

[blackieNYC]

I would think the fx30b would do as good a job as any BUT I'm not sure if the threshold will give you the subtlety this might require.  I have one.  PM me a reminder and I'll try this out for you Monday or Tuesday.

[R.G.]

Conceptually, it's simple. The pieces are:
Envelope detector
Comparator, with variable reference
Electronic switching to gate in the delay
The delay
Boxes, jacks, buffers, wire, yada, yada.

The normal path is set up to always be sent from in to out. The delay is fed the input signal only by the signal switching only when the comparator senses the signal level is above X. X is set by a pot. You may want to have a control which "stretches" the gating time a bit to avoid just delaying blips, or to have the comparator have hysteresis so it starts at some high level, but only "lets go" at a much lower level after the signal decays.

You're almost certain to have to learn to adapt your playing style to make the delayed-chord stand out properly without getting slices of what comes after it. Simple circuits can do the switching be they're not smart enough to know what you want, which changes from time to time. 

[niftyprose]

Thanks both. I'll PM Blackie tomorrow, in case the DOD can do it, but maybe it's time to get technical... Best, NP

[blackieNYC]

edit: after RG's response.  "...always in to out..."   That is a splitter/blender in essence, though if you incorporate it into the gate pedal, or v.v., it can be scaled down in design. A passive split perhaps, a passive mix perhaps. Maybe some gain makeup. But what he is saying is exactly what I found in a real world test.
Always, with that guy, you'll find. 
Here's my PM response.
Just tried it - the threshold "sensitivity" of the fx30B will do this at a point a little below its max cw setting. On your playing style alone, digging in a little can trigger the gate and you can easily play under the threshold. This will work out nicely for you. Typical gate.
What you will need however is a splitter/blender. This is a little thinkier than I thought.  The gate alone is a single audio channel - the threshold determines when the door is shut, and when it's open. The threshold can look at the input from the guitar or the input from the loop return, but when it shuts the door nothing gets thru. When it's looking at the loop return, it is "deciding" whether or not to insert the loop, not whether or not to add the loop.
A splitter blender in its own box is versatile and wonderful, but you could incorporate it into a gate design. Think of loop A as straight-thru, and loop B has a delay. With a stomp switch you add or don't add loop B to A. With another switch ( at least 2p2t for TB) you could inject the gate into loop A (I would think right at the input before the split, for a conventional front-of-chain gate)or loop B.