Fairfield Circuitry - The Barbershop (gut)  [traced]

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cortezthekiller
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Post by cortezthekiller »

lugs 2 and 3 should be disconnected from the top of the 9.1k resistor and lug 1 should connect to it.

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Post by WhiteKeyHole »

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I figured D1 might be a zener. Also, thanks for the correction on the sag control, Fairfield.

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Post by briggs »

I'm liking the look of this little circuit. I loved the demos that are about on youtube, I might have to give it a go :)
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Post by analogguru »

....and if you are not a crackle-fetishist you can modify the circuit as shown below. You can also add a 100n cap followed by a 1M pulldown between the drive poti and the second FET, but this is a minor change.

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Post by briggs »

Take the DC off of that pot. I would be tempted to set the circuit up with the 100n 1M as AG says just to remove all traces of DC on the pots.
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Post by IggY »

Mr. Fairfield: is C7 in reality placed as drawn in the latest circuit diagrams,
or is it placed on the other side of POT2?

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Post by fairfield »

Iggy, indeed C7 is placed between R10 and POT2.

Crackle fetish? Sweet stuff, my new fetish is much less expensive than my last. Alls I needs is a battery, a pot and a few alligator clips....mmmmm. It actually makes more of a swooshing sound, like rubbing your socks against a carpet.

It was a conscious choice, I like the fact that the output impedance can be 10x lower.
Guillaume Fairfield
Fairfield Circuitry

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Post by IggY »

fairfield wrote:Iggy, indeed C7 is placed between R10 and POT2.
Thank you Guillaume,
from watching and hearing the video on your site it seemed more plausible.
Both for the soundcharacter change after the pot is being turned to right,
as well as for the fact that this change sets on immediately.
With the timeconstant of the 220uF and the sagpot,
that change would take ages otherwise (assuming a modest currentconsumption by the transistors).

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Post by briggs »

I'm going to build one up. I'm loving the demos and I'm into low gain overdrive!

Did you ever contemplate using SK170/117 fets in the design of the barber shop Mr F?
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Post by WhiteKeyHole »

Toaster strudels.
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Fair2.png
Fair2.png (5.18 KiB) Viewed 1454 times

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Post by TJSmitty »

Sexy circuit.

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Post by dap9 »

Has anyone put this on a bread board or anything yet? A few guys over at HC got the pedal and absolutely raved about it. The demos seem OK to me, but now that I've heard the reviews, I think this may be right up my alley... I'm all about the subtlez!

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Post by Cow4prez »

fairfield wrote:The 100k log is Drive and the 10k log is Volume. Indeed about the 10k linear, but Sag is also adjusting the bias of other transistors. Who said there was nothing between the first and last stage?
The plot thickens.

Don't get too excited about this circuit. Like so many others, the schematic doesn't explain why it sounds good. I was wondering...

Who here would enjoy receiving a newly purchased pedal with printed schematics in the box?
sure and what a "novel" idea, and it's good for repairs, modification, re-interpretation, analysis, discussion and maybe even cloning. But don't goop the schematic because that would defeat the purpose ;)

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Post by theblackman »

wow this is a really nice sounding pedal from the youtube vids.
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Post by Beedoola »

Anyone build one yet?

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dap9
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Post by dap9 »

Not sure if y'all have seen this, but a guy at HC posted this clip of a bunch of dirts (OCD, DLS, Tim, Screwdriver, etc) and the Barbershop. It's pretty cool how the Barbershop adds some sparkle to each of them. It's been a while since I've read this thread, so hopefully the scheme's accurate, b/c my curiosity has not officially be piqued!

https://www.youtube.com/watch?v=forpvJDj0-0

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Post by daz »

i've sketched up a rough stripboard layout. I'll see if I can put it up tonite.

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Post by uncleboko »

I read "Barberpole" at first - wishful thinking!!

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Post by daz »

Here's my shot at it. Have some grace, first time doing it on a stripboard and done in a hurry.
Let me know any errors.
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Post by fairfield »

Fairgo Shaver...
I don't know if I'm out of line here, but how about keeping the name intact?
Why pretend that this is something it's not...

If any of you read japanese, this guy has built one with a few little mods.
http://blogs.yahoo.co.jp/mitani518/folder/1181715.html
Guillaume Fairfield
Fairfield Circuitry

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