E&MM String Damper

[Mark Hammer]

Now that I can go crazy making PCB's with glossy photo paper, I put together an E&MM String Damper last night using Francisco Pena's layout.  This is a layout he posted some time back at http://f-pea.tripod.com/projectimages/, and is not currently in the list of projects at Tonepad.

There are a million ways for me to make it wrong, but I was a good boy last night and tried to do everything right.  Still it performs erratically, and seems to need extended silence to be able to recover.  The attack pot also doesn't seem to function very well, although th the decay one seems to behave fine.  Has anyone had any experience building this?  Is the layout verified to work?  Are there any bugs you caught after posting Francisco?

I'm hoping to have a String Damper, PAiA Gator, and Slow Gear clone running and compared.

[jeeeyum]

I built it a long while ago.  Worked perfectly from the start (or I assume perfectly, it sounded like it was described to sound like).  I remember having to edit the parts layout to get the traces and resize it to print, but that was back in my early newbie days.

But yeah, it works and sounds good, do you have a layout for the slow gear?  I have always wanted to build one of those.

[Paul Perry (Frostwave)]

Mark, that link seems gone, perhaps you could post it on YOUR site! if you still have it.

[RickL]

I built one a while ago and from I remember it seemed to work about the same as the Gator and the Slow Gear. I'll dig it out if I can find it and reaquaint myself with it. If reality is different than memory I'll report again.

[pinkjimiphoton]

time to bump da zombie back to life...

paging doctor hammer...

mark...
what were the chips on this thing supposed to be? that's the only thing not maked on the layout, and i'm trying to dick around with it...

hope you remember!!

[Mark Hammer]

I finally did get it working.  The Decay time is much less useful than the Attack time (ever heard of the butt of your hand?), but it does what's advertised.  Quite frankly, it may find its greatest relevance in a parallel processing system where several different tones are blended in some chronological order using two or more of these beasts.   At the mixer output, for example, we'd morph from one tone that has a fast attack and slowish decay, into a different tone that has a slower attack.

The chips are a TL072 and an LM13600.

[pinkjimiphoton]

thanks mark....
i'm assuming i can use the lm13700 for the dual ota?

i did find the project on francesco's site, which led me to YOUR site, of course...so i'll get to work on this...looking forward to it!!
thanks for the quick response and headsup my friend!

peace!

[Mark Hammer]

If the goal is simply to get slowed attack, I find the PAiA Gator a more pleasing circuit.  Although I understand if the overly cautious use of a 3080 for anything that could be accomplished another way is part of your thinking.  (I'm reminded of Elaine Benes on Seinfeld classifying men as either "spongeworthy" or not)

[artifus]

just found this in an old book i forgot i had: