Barber Electronics - Small Fry  [traced]

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analogguru
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Post by analogguru »

"Mitch T" posted here:
viewtopic.php?f=7&t=781

guts from his Ex-Small fry.

Here are some other:
http://cgi.ebay.at/BARBER-SMALL-FRY-Ove ... dZViewItem

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Post by tuemmueh »

I'd be heavily interested what is meant with this sentence:
Barber adjustable phono style recovery stage- Most of our op-amp based overdrive pedals use a cool old style phonograph circuit to recover the frequencies lost in the overdrive stage, this worked great for vinyl and now works great for guitar overdrive!
http://www.barberelectronics.com/SmallFry.html

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Post by analogguru »

That´s easy:

To avoid overloading before cutting of a record the bass was attenuated and the treble was boosted. During playback the bass was boosted again to its original level and the treble attenuated too. This was achieved with a special EQ-amplifier, an example can be seen here:
http://www.jens-wesemann.de/phono.jpg

R1, R2, C1 and C2 in this schematic are responsible for that. Now if you make R1 and R2 adjustable then you´ve got it, what is described there.

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Post by tuemmueh »

Ah, okay, that's interesting, thank you ag!

Now the last big secret would be the "Note shap"-control ... any information on that one?!

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Post by Dirk_Hendrik »

Mitch T is a personal friend of mine. Thanks Mitch too ;)

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Post by Mitch T »

Posted that pic in the Burn Unit topic. (Hi D_H !)
To my ears, the 'Note Shape' changed the bass response and to a cerain degree the attack/compression.
It was an important pot for the entire sound, although it seemingly had a similar function as the
'Dynamics' control. The fact that it was highly tweakable was both a drawback and an advantege.
Dialing in a usable sound was no problem (I'm not a tech, but I'm not a moron :wink: ) but my main
problem was that I didn't like the 'basic' sound. Like the Direct Drive, it has a distinct sound, changing
your basic tone considerably. It got a bit lost in the mix as well, sounding seemingly more compressed
than other pedals.
I wouldn't recommend building a clone :mrgreen:

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Post by Liquids »

Mitch T wrote:Posted that pic in the Burn Unit topic. (Hi D_H !)
To my ears, the 'Note Shape' changed the bass response and to a cerain degree the attack/compression.
It was an important pot for the entire sound, although it seemingly had a similar function as the
'Dynamics' control. The fact that it was highly tweakable was both a drawback and an advantege.
Dialing in a usable sound was no problem (I'm not a tech, but I'm not a moron :wink: ) but my main
problem was that I didn't like the 'basic' sound. Like the Direct Drive, it has a distinct sound, changing
your basic tone considerably. It got a bit lost in the mix as well, sounding seemingly more compressed
than other pedals.
I wouldn't recommend building a clone :mrgreen:

I enjoyed mine--it was the last pedal I bought before I went DIY. I sold it afterward, once I had breadboard/built stuff I liked better and used more. It was the best pedal I had found and could afford for a true, smooth, dare I say 'dumble' style pedal (as opposed to marshall or tweed, slight OD, or shred style), if you will, that had no waiting list or huge price tag. I'm not saying it's a dumble in a box, but it's got a distinct tone in that general catergory.

It is a bit compressed and sustainy, with a lot of the rough edges smoothed out. It doesn't do dynamic low gain though, no, its too dark, smooth, and compressed for that. It's kind of like a mesa is in that regard - you turn it on and you 'get that sound.' The base tone of which is always there, but it's a good sound. Not trying to be a 'transparent' OD. In a mix I found it excellent since I like that sound, though I do personally prefer the zendrive circuit for that kind of thing, which is more dynamic but had less apparent gain, now that I've tired that on the breadboard...but I didn't build that one, either. I prefer working with core tone of mu-amp based units for those sounds, since in general I don't like some of the artifacts that 'come with the territory' of op amp + diode clippers in general. For those that particularly like op amp types, it's definitely worth finding out more about.

So while I'd not built one, I'd like to know what the concept/implementation behind the 'dynamics' control on this one was. If it was just blending in a diode for varying levels of symmetry/asymmetry, as I would now guess, or what have you, it was a great feature for the average guitar player that took it above most OD pedals. More interesting than the 'voicing' control on the Zen, IMO. Whatever that control is, I mostly set it and forget it for the smoothest sounds since that's what I was going for, but it was nice way to make the pedal very versatile and offer flexibility, and to shape tone outside of standard EQ and gain. You could dial in some smoothness or edge outside of the tone control. Likewise, the tone control was nice in that, to my ears, it left most of the EQ alone and merely shaped the high end.

The internal note shape, control to my knowledge, is pre-bass control. Nothing revolutionary, but useful.

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Post by culturejam »

Just got one of these. I will be posting fresh photos and tracing it over the next couple days. :thumbsup

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Post by madbean »

That's cool---I'd say just go off the LTD schem...it's probably got a similar design. Or, not.

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Post by culturejam »

It's gotta be kinda similar. But it's got a lot more tweakability than the LTD.

There are four trimmers inside: Mids, Bass, Presence, and Note Shape.

It's got the "Dynamics" control on the outside. (I think I see what this does without even pulling it apart)

And there is also the mysterious unmarked three-way toggle switch, which provides "three distinct styles of symmetry". Diode clipping toggle switch, I think. It's a center off switch, I assume, but even when off there is still a fair bit of clipping. So maybe some of those diodes are always in the loop. The wiring of it is not immediately obvious to me, but I'll probe it out.

IMG_9374.jpg

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Post by bigorangefan79 »

tuemmueh wrote:Ah, okay, that's interesting, thank you ag!

Now the last big secret would be the "Note shap"-control ... any information on that one?!


The note shape is prescence (adjusting the point that treble is clipped)

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Post by bigorangefan79 »

The dynamics control adds in ge clippers to ground

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Post by madbean »

The diodes could be connected to different areas of the circuit which may be why the switch is wired that way.

I'm not sure where the 680p cap does though...maybe in parallel with some of the diodes. It looks like the Presence, 220R, 68n are mixed with the note shape and/or diodes. That 91R is in line with the PS, I bet---he likes those.

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Post by Duckman »

What kind of connector is he using for the LED? Nice detail.

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Post by culturejam »

bigorangefan79 wrote:The dynamics control adds in ge clippers to ground
Cool. That'll make things easier when I do the full trace. Thanks.
madbean wrote:The diodes could be connected to different areas of the circuit which may be why the switch is wired that way.
Yeah, I can't suss it from just looking at it.
madbean wrote:I'm not sure where the 680p cap does though...maybe in parallel with some of the diodes. It looks like the Presence, 220R, 68n are mixed with the note shape and/or diodes.
Yes, I think Note Shape is a finer adjustment of the Presence control.

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Post by culturejam »

Somebody sent me this schematic and asked that I post it. I was told this was traced directly from a Small Fry pedal.

It seems reasonable to me, and it shares some characteristics with the LTD. Although it is also quite a bit different.
SmallFry.png

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Post by madbean »

That 3k should be connected from the junction of the 10n and 82n to the junction of the mid and bass pot. Or, at least something is not right there.

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Post by culturejam »

madbean wrote:That 3k should be connected from the junction of the 10n and 82n to the junction of the mid and bass pot. Or, at least something is not right there.
That's kinda what I thought, too. On the LTD, there is no resistor there, just a "wire".

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Post by culturejam »

Update from the anonymous donor after re-consulting tracing notes.
BSMFRY.png
BSMFRY.png (9.37 KiB) Viewed 4020 times

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