# Minnow / FSH-1 Speed Mod?



## Kinski (Feb 11, 2021)

I LOVE this circuit! However, I wish the slowest setting in the S&H mode would be slower. Much slower. Is there a way to do this? Perhaps some resistor?

I really love the fastest speed, so no adjustments needed there. Any suggestions would be greatly appreciated!


----------



## Chuck D. Bones (Feb 27, 2021)

Make C10 bigger.  A 1uF film cap will fit there and reduce the speed 3x.  You could also use a tantalum cap.  If you use a polarized cap, figure out when side of the cap connects to the SPEED pot and make that the + end of the cap.

If you want to preserve the max speed, then make R28 3x smaller (68K).

Avoid using aluminum electrolytics, they are leaky and might make the LFO stall.


----------



## Kinski (Feb 27, 2021)

Thanks! I’ll try this out.


----------



## Chuck D. Bones (Mar 9, 2021)

Well?


----------



## r.callison (Mar 9, 2021)

I'm going to be trying this mod out, once a couple parts come in from Mouser. Any other recs on mods to this build @Chuck D. Bones ? I've built a pair so I can side by side the stock and modded ones.


----------



## Kinski (Mar 9, 2021)

Chuck D. Bones said:


> Well?


Life has not given me much free time. Might be able to get to it this Thursday or Friday. I’ll report back when I make it happen.


----------



## Chuck D. Bones (Mar 9, 2021)

No problem, just checking.


----------



## Chuck D. Bones (Mar 9, 2021)

r.callison said:


> I'm going to be trying this mod out, once a couple parts come in from Mouser. Any other recs on mods to this build @Chuck D. Bones ? I've built a pair so I can side by side the stock and modded ones.


Do you get enough sweep with the FILTER pot dimed?  I fooled around with a few different mods on my breadboard, but most are too involved to implement on the PC board without major surgery.  At the end of it all, the part of the effect I liked most was the S/H.  I got bored with the envelope filter pretty quickly.  Makes everything sound like the soundtrack to a 70's porn film.  Bwow-buh-bwow-bwow.


----------



## Barry (Mar 9, 2021)

Chuck D. Bones said:


> Do you get enough sweep with the FILTER pot dimed?  I fooled around with a few different mods on my breadboard, but most are too involved to implement on the PC board without major surgery.  At the end of it all, the part of the effect I liked most was the S/H.  I got bored with the envelope filter pretty quickly.  Makes everything sound like the soundtrack to a 70's porn film.  Bwow-buh-bwow-bwow.


There were soundtracks on those? Funny I never noticed!


----------



## Chuck D. Bones (Mar 9, 2021)

Here's a strange bit of music trivia: In the 1974 art movie _Emanuelle_, the soundtrack contained an unauthorized cover of King Crimson's Lark's Tongue in Aspic, part 2.

Are we far enough off-topic yet?


----------



## Kinski (Mar 11, 2021)

So, I can’t access C10 without taking the whole pcb how of the enclosure. And I don’t really want to do that as I’ve got the thing perfectly quiet and working great. I can happily live with the current speed parameters. Sorry, if I wasted your time. I appreciate your input. And it looks as though others here are interested in this modification, so still good that this has been brought up. Thanks again!


----------



## r.callison (Mar 13, 2021)

@Chuck D. Bones Did the slow mod, really love how that one worked out. The build is super noisy now that it's in the enclosure, think @Kinski has a thread where he addresses that. Built an identical pair, and they're borderline too noisy to use, and it seems like it's a problem of how close IC2 is to the output jack. I've got a pair I built, and they're both working exactly alike now that they're modded. Couple things:

In bypass w/ the input unplugged, the things make a terrible microphonic sound. When the input's in, not bad, but the same microphonics show back up, when the unit's on and the S/H feature ends up grabbing them and just goes to town on that even if i'm playing nothing. When i lift the pcb out of the enclosure the sound goes away, but when it's all mounted the noise comes back. 

Note, I tested them side by side modded and unmodded, the above problem showed up in both.


----------



## dawson (Mar 13, 2021)

Kinski said:


> So, I can’t access C10 without taking the whole pcb how of the enclosure. And I don’t really want to do that as I’ve got the thing perfectly quiet and working great. I can happily live with the current speed parameters. Sorry, if I wasted your time. I appreciate your input. And it looks as though others here are interested in this modification, so still good that this has been brought up. Thanks again!


I just had a thought-
You could raise the amount of capacitance by adding a second capacitor in parallel with the first- if it fits I'd try just barely tacking it on at first so that it'll be easily removable if you don't like the results.


----------



## Chuck D. Bones (Mar 13, 2021)

What kind of guitar are you using?
I hear the usual 60Hz in bypass when my Strat is plugged in.  Engaging the filter runs all that thru the filter.  With the FSH-1 in Envelope mode, the filter freq is tuned down low when there is little or no signal and the noise is not so obvious.  In S/H mode, the filter jumps back & forth and now the 60Hz pickup is more obvious.  I think it's normal.


----------

