Revised Kay Fuzz Tone schematic

[analogguru]

The green circled resistor is the one in doubt.  if you compare it to the red circled resistor, you can see that its definitely a 10k.

Concerning the input filter:
If you look at the schematic of  the Ibanez Standard Fuzz (and clones like Bruno Fuzz Machine):

Ibanez Standard Fuzz Schematic

you will notice, that there is also no input-filter.

And don´t forget the 100n (C3) on the emitter of the first transistor (will produce less gain at lower frequencies) and the large value of 2n2 (C2) between collector and base of the first transistor (will reduce gain at higher frequencies) which is also acting like a bandpass-filter.

I assume that the Kay is an absolutely minimized version for the reason that they even did not use the base resistors (470 E or 1k) or a footswitch.  IMHO this is more a novelty.

Fender used in the Blender also a pot in the filter-section as a tone control.

analogguru

[g3rmanium]

Here is a movie I made of the pedal in action.... http://theinside.net/misc/Kay Fuzz/Kay Fuzz.MPG

That sounds great. Like mine should sound like, I guess. Maybe I should record some clips as well.

[g3rmanium]

More gut shots!

[g3rmanium]

Here is the updated diagram:

[g3rmanium]

Here are the original blog posts:

Revised Kay Fuzz Tone schematics

and

Revised revised Kay Fuzz Tone schematics.

The last one contains clips (mp3, ogg).

[ustompsteve]

On the schematic on my site that Spaceshot helped me with there is a 50k pot with a 200k resistor after it. I am pretty sure he got that from a real unit. Maybe some were different.

Any idea what moving the 2n2 C2 from between Q1 and Q2 to before Q1 would change? Also the changing of the 10k to 100k?

I will try and change mine in the next few days.

I really like the way mine sounds as is. That would be great if it ends up sounding even better.

--Steve

[Jackie Treehorn]

Thanks for the kind words guys.  I really like g3rmanium's clip, too.

I put 2n4401's in the octave section and I remember spending some time testing and matching to get a strong octave.  I think Lanois' pedal in "Orange Kay" has a pretty strong octave.  I am going to have to put a switch where Mark suggests to cut the octave.  Thanks for the tip.

It does look like a 10k.  I was more or less implying that it sounds better to me with the 2n4401 transistors to use a value in the 47k-100k range.  Sorry for the confusion!

[Joe Kramer]

. . .  I dig the way you do business, Jackie. . . .

[Dan N]

Tip of the cap to Analogguru! I never noticed that cap was on Q1. I wonder how it affected the proper function of Q2, the phase splitter. Has every clone been f**ked from the get go?

Looks like they messed with the pot. 50K + a 200K resistor the begin with (original schematic and spaceshot's), them just went with 250K (Roger Lavallee and g3rmanium). I wonder which Sir HC has?

Argh!

Thanks again for your photos, g3rmanium and Sir H C! Thanks for the (hopefully) final schematic, analogguru!

[g3rmanium]

Looks like they messed with the pot. 50K + a 200K resistor the begin with (original schematic and spaceshot's), them just went with 250K (Roger Lavallee and g3rmanium). I wonder which Sir HC
has?

I measured the resistance between pin 1 and pin 2. With the pedal all the way up, it was around 8 KOhm. With the pedal all the way down it was close to zero. Maybe this helps? The treadle has a really short sweep anyway.

[ustompsteve]

I updated the schematic and layout on the http://ustomp.com site with the updates/changes.

I left the 50k pot w/ the 200k resistor. This could be replaced with a 250k pot and a jumper depending on which way you want to go.

--steve

[Dragonfly]

you might try doing a layout utilizing a transistor array like the CA3086

[Arn C.]

I like your thinking Dragonfly!  I have a few of those IC's!!!!


Peace!
Arn C.

[Sir H C]

you might try doing a layout utilizing a transistor array like the CA3086

Great for places where you need a matched pair (such as the octave devices).

[burningman]

I have a couple of questions, that I thought maybe someone could answer. First, which would you say is more suitable for this project, a log or linear pot? Right now I am using a 100k Crybaby hot potz ecb24. I was also wondering what audible difference should there be when I drop the 200k resistor for a 150k to make up the 250k resistance to ground with the 100k hot potz? I've tried this already but haven't heard any difference.
Thanks

[roseblood11]

Hi,

could anybody post a verified layout please? some of the links in this thread are dead...

[roseblood11]

ups, I meant to say "veroboard layout"... Of course I know the pcb layout on ustomp.com

[pinkjimiphoton]

So the fuzz is controlled by the wah pedal?

@mattpocket
this is a pedal, not a "wah-pedal"... a wah-pedal is a pedal which produces a wah-sound.

The fuzz is not controlled by the pedal, only the output volume of the fuzz (and the tone-color a bit).

analogguru

incorrect, the treadle controls the TONE of the fuzztone. thats it. sorry to bump a zombie, but i see so much misinfo spread around...

[Mark Hammer]

Kay did that just to mess with our heads.

[pinkjimiphoton]

its still workin

i LOVE my ancient and venerable kay fuzztone. it was my first. it lead me to the big muff pi that totally changed my life. until the fuzzface came along

lol

analog guru seems to have pretty much disappeared.
mine, it changes the tone only, and not the volume or fuzz level as alleged.
the first one i got was the same.  so.....

black cat has an interesting twist on this circuit, but i think they went under.