Barber - Small Fry  [traced]

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Re: Barber - Small Fry

Postby madbean » 27 Feb 2012, 20:45

That looks right to me. I'm a bit bothered by the switching, though. I'm not quite understanding what is supposed to happen when the switch is it supposed to short out the one diode on the right to make the clipping symmetrical (in the fb loop--I get what's happening with the GE diode)? That's my guess.

Re: Barber - Small Fry

Postby culturejam » 27 Feb 2012, 21:46

Maybe the switch is:

"Switch is on/off/on, left to right it's: 4 symetrical clippers in loop, 7 clippers in loop, 7 clippers in loop and 1 ge to ground." :secret:

Just looking at it makes my head hurt. :lol:
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Re: Barber - Small Fry

Postby beedotman » 27 Feb 2012, 22:31

Thanks guys!

This is really nice sounding drive! 4 life!
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Re: Barber - Small Fry

Postby bucksears » 31 May 2013, 02:59

Resurrecting this one - have a couple of questions:

- Is this schem verified/good?
- Has anyone confirmed how the toggle switch connects?
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Re: Barber - Small Fry

Postby bigorangefan79 » 31 May 2013, 13:58

The most recent of the two schems is correct. The toggle switch is on/off/on, left to right it's: 4 symetrical clippers in loop, 7 clippers in loop, 7 clippers in loop and 1 ge to ground. The bass, mid, presence, and note shape are trim pots.

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Re: Barber - Small Fry

Postby Mbas974 » 01 Jun 2013, 22:25

Concerning the hard-clipping section, how much big should be the POT for having NO CLIP at all (larger I see around is 10K..) ??
I'd like using this POT like a switch also... :blackeye
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Re: Barber - Small Fry

Postby IvIark » 09 Feb 2014, 17:10


"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

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Re: Barber - Small Fry

Postby darkbluemurder » 12 Jun 2017, 10:33

Thank you very much for sharing the schematic, that is very useful.

I have recently acquired the dual channel version (the Burn Unit EQ) and found that it sounds quite different to the Small Fry. One of the differences is that the Burn Unit has a 25k mid pot which allows for much more midrange. The second noticeable difference is the presence resistor to Vcc - 220 in the Small Fry vs. 470 in the Burn Unit. Both changes make the Burn Unit sound warmer and smoother.

I then did the following mods to my Small Fry:

1) Inserted a 10k resistor between the mid pot and the 3k resistor which is connected to the bass pot. So instead of a variable resistance of 3k to 13k I have now 13k to 23k. The lowest setting is now equal to the highest setting before the mod while the highest setting goes far beyond.

2) Inserted another 220 resistor in the presence line, which is like turning the presence control down a notch.

The modded Small Fry now sounds a lot closer to the Burn Unit, even though it is still a bit brighter but it's no longer too bright.

These are the mods I could do without taking the whole thing apart. Of course it would have been best to change the 10k trimmer to a 25k one for the most possible range.

Cheers Stephan

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Re: Barber - Small Fry

Postby mully » 27 Feb 2018, 21:58


I'm a newbie when it comes to these things but I have a hard time understanding some things here. On the original Small Fry the Tone Pot just has two lugs connected to the circuit (3 & 2) and the dynamics pot as well (although different ones 2 & 1) and on the veroboard layout (and the schematic) all lugs of the pots are used. Am I missing something here or are these schematics not 100% correct?

And another question: regarding the clipping switch: does the "wire" from lug 1 of the switch have a connection to both diode arrays or just the lower one with D7, D6 and D5? In the schematic the lower one with the three diodes is connected to the switch between D6 & D5 (indicated by the black dot) but in between D2 and D3 there's no dot. From what I understand this would mean there's no connection. But when looking at the veroboard layout there seems to be a connection (which seems logical - but there's no dot in the schematic).

And another question would be regarding the Resistor (91) which is connected between the 9V source and V+ in this schematic. Which effect does that have? Would that decrease the voltage going to the IC? I realize that VCC is acting as the virtual ground / bias for the circuit which usually is 4.5V in most pedals as far as I understand, but on most other schematics I have seen, there was no resistor inbetween the Battery/DCjack and the IC - and looking on Dave's LTD schematic there's no V+ just 9V and / 4.5V as I would have expected.

Just honestly trying to understand these things... as I said... I'm a total noob trying to get my head around these things.

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