quadrafuzz switching

[rove]

Hey, I have a paia quadrafuzz I built a little over a year ago, recently it started buzzing something awful after months of working fine so I replaced the in and out leads with grounded wire.  I had previously removed all the jacks I am not using, leaving 2 inputs 2 outputs and the footswitch jack.  It doesn't buzz anymore if I have it upside down (?), but I want to ultimately put it in a DD enclosure for better shieldinng (currently its in the paia rack).  Either way I want to change the switching, as there is a momentary pause when engaging the effect making it impractical to turn on mid song.  How do I get rid of this pause? thanks for any suggestions.

[rove]

oops, schematic link might be useful:

http://paia.com/quadrafz.htm

[jimbeaux]

I had the same switching delay problem. Ran across an answer to this in a CA column in "Guitar Player" (Oct. 1984).

",... Lower R49's value. You may need to lower the value of R53 as well if there are pops or squeals when you hit the foot-switch"

Can't remember what values I used - but I can check my quadrafuzz tomorrow & post the values that worked for me.

[Processaurus]

Hi, I bet that buzz is because one part of the chassis isn't grounded together with the other parts, so its acting as an antena. 

How do you like the sound of that circuit?  I have a PCB for it but haven't made it yet. 

[rove]

Yes, it is definitely an antenna type thing as radio signal comes thru.  I will have to recheck my ground scheme.  This was one of the first things I built...
R49 is 470kohm and R53 is 680kohm.
I like the sound of this circuit quite a bit, I have not modified it at all and it is my only fuzz, surrounded by overdrives!  I would use it more if it weren't for the switching delay! 
thanks for the help.
Paul

[jimbeaux]

I'm getting almost instant footswitch changes with R49 = 120K   &  R53 = 220K

Cutting the values in half, still caused a noticeable delay - but with the above values - it works fine.

[rove]

thanks for the R values, Jimbeaux, much appreciated.
I have tried a couple different combos of resistors and right now I'm at R49=100K & R53=182K.  There is still a noticeable delay, though it is much improved.  It just barely chops the attack.  Gonna keep going down in value and see if I get the dreaded pops and squeals.  How would I modify this box to true bypass? thanks again,
Paul

[rove]

OK so I settled for now on R53=182K and R49=1K.  This seems to give me what I want, ie not having to anticipate the pause caused by the switching while in the middle of a song.  I have not noticed any extra pops or squeals and, in fact, the unit seems even quieter, but that could just be the angle of the chassis...

[rove]

I think I figured out the grounding problem as well.  One of the nuts that holds the pcb to the rack keeps coming loose and therefore messing up the grounding--in other words the nuts ground the pcb to the chassis and playing thru it loosens one up from the vibrations.  Need to get a hot glue gun and get that sucker stuck.  Still wanting to put this into a DD enclosure, but there appears to be a shortage of these currently...  Anybody build a quadrafuzz in another type enclosure and wanna share some tips or pix?
thanks,
Paul

[caress]

i'm going to be housing the quadrafuzz into a non-rack enclosure in the next few weeks, so i'll let you know how it goes...