EarthQuaker Devices - Hoof Fuzz

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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icziko
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Post by icziko »

bato001 wrote:
icziko wrote:
basicchannel wrote:
andregarcia57 wrote:The original leds are 3mm clear red?
Yes.

[ Image ]
Question: During play, can You see flashing all D1-D4 diodes or only D3-D4?
Clipping diodes, even LEDs, do not normally light up at all.
Thanks Bato.
D3 and D4 diodes light up only when I hit strings. When strings are muted D3 and D4 are not lighten up. I would say that even D1 and D2 are lightening up during strumming but only slightly and it depends of Sustain knob adjustment. More sustain = more D1 and D2 light up.
If this "phenomenon" does not have place in original Hoof Fuzz than there is something wrong with my built unit.
Thx

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bato001
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Post by bato001 »

icziko wrote:
bato001 wrote:
icziko wrote:
basicchannel wrote:
andregarcia57 wrote:The original leds are 3mm clear red?
Yes.

[ Image ]
Question: During play, can You see flashing all D1-D4 diodes or only D3-D4?
Clipping diodes, even LEDs, do not normally light up at all.
Thanks Bato.
D3 and D4 diodes light up only when I hit strings. When strings are muted D3 and D4 are not lighten up. I would say that even D1 and D2 are lightening up during strumming but only slightly and it depends of Sustain knob adjustment. More sustain = more D1 and D2 light up.
If this "phenomenon" does not have place in original Hoof Fuzz than there is something wrong with my built unit.
Thx
Make sure you don't have a solder bridge at the solder pad where the leds go into the cap on those diodes. It's not impossible for clippers to lite up, but it's not the norm.
"Ever wondered how some of your favourite guitar players got their tone? Me too. Probably a good amp and lots of practice." Little Lord Electronics Homepage

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anselm
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Post by anselm »

bato001 wrote:Clipping diodes, even LEDs, do not normally light up at all.
any diode (xept leds) do not normally light up at all
not only clipping
rectifier diodes behave in the same way
***
icziko, when led conducting curren, it emmits light
it made for it
more current - more light
when led lights up, it clipps the signal
lightin up is perfectly normal

have fun


xqz my engl :wink:

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icziko
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Post by icziko »

anselm wrote:
bato001 wrote:Clipping diodes, even LEDs, do not normally light up at all.
any diode (xept leds) do not normally light up at all
not only clipping
rectifier diodes behave in the same way
***
icziko, when led conducting curren, it emmits light
it made for it
more current - more light
when led lights up, it clipps the signal
lightin up is perfectly normal

have fun


xqz my engl :wink:
Thx Bato & anselm
I checked my built around LED diodes and there is no bridge between diodes and caps and solder site. Moreover I checked polarity of diodes (using diode mode on DMM) and it is OK so by taking that fact and Your answers I think it is normal.
My only concern is that D3-D4 diodes lights more than D1-D2. D3-D4 lights fully according to string strum and D1-D2 similarly but they are lighter once I crank fuzz sustain fully up. I think that D3 and D4 are 1st stage of clipping and D1 and D2 for 2nd stage and for some reason 1st stage clips signal more than 2nd stage. Does it make any sense?
Thx

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ClassicFuzz
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Post by ClassicFuzz »

Hey,
I was just wondering, after reading the whole thread, if the Hoof schematic might have slightly changed?
1. Judging by this video by EQD they are now using MP38a transistors:

2. I also realised that they aren't using any ceramic caps in the circuit anymore. Could it be possible that they changed them to higher values to increase the gain in order to use low gain MP38a's?

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houseofglass21
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Post by houseofglass21 »

I have a Hoof and love it. But I wish it had a bit more gain. It gets to about 90% of what I want. Would changing the gain pot to a higher value achieve this and if so what value would you recommend? Any ideas or help are much appreciated.

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plush
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Post by plush »

houseofglass21 wrote: 24 Nov 2021, 15:41 Would changing the gain pot to a higher value achieve this and if so what value would you recommend?
It won't make much difference.
You'll have to tweak one of the gain stages (or all of them).
https://www.electrosmash.com/big-muff-pi-analysis

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