ADA flanger threshold question

[jmasciswannabe]

While debugging I finally heard a swoosh after jamming my strings and adjusting the trim pot. I nearly pissed myself with joy cause I have been trying to get the thing working since I ordered a revision 2 board a bit ago. Anyhow, I was able to track down the problem. 13k where the 1m3 should have been.    It did make me wonder, however, how sensitive the threshold pot is supposed to be. With the right resistor, it doesn't seem to make a difference with the pot ccw or cw. Do any of you single coilers get a good threshold reaction? I guess I was expecting like an envelope filter threshold. Strangely enough that was what happened with the 13k resistor, but you would really have to hit the strings HARD and the flange would only last a second or so. Maybe fiddling around with the value on that resistor could find a happy medium?

[StephenGiles]

I never bothered with the noise reduction circuitry.

[moosapotamus]

As I understand, it's really about noise reduction... or actually, just a way to make the unit absolutely quiet when not playing by blocking any clock/modulation feedthrough when the input drops below the threshold setting. My guess is the idea was to make it like something that you would NOT hear, as opposed to an effect-type of control.

~ Charlie

[StephenGiles]

I never bothered with the noise reduction circuitry.

And the other reason was that I could not trace the FET.

[jmasciswannabe]

Okay. So the threshold just keeps the bleedthrough at bay while not playing, but the when you start playing you are going to get the effect regardless of the threshold setting?

[Scrutinizer]

Well, that's one way to use that control. At higher threshold settings it will gate the flange effect in response to playing dynamics. For instance, one can dial up a drone note effect (enhance>90%, range=0, manual sets pitch) then set the threshold high to bring that flanger-generated-drone in and out just by playing harder or softer.

[DavidRavenMoon]

I remember those when they came out.  They said in the ads the threshold was an effect so the flanging would only happen when you hit the strings hard, if that's what you wanted.  Wasn't for noise reduction.

[Mark Hammer]

Well, I guess one has to always differentiate ad copy from true functioning.  The circuit is very very similar to that used on the CE-1 chorus ensemble which is specifically directed at keeping noise at bay.  Think of the threshold control as something which can always be used to accomplish noise reduction and sometimes used to produce a dynamic effect-change.  How much you want it to do of either is essentially a function of how much gain is built into the first op-amp stage in the sidechain.