Dunlop - Eric Johnson Signature Fuzz Face EJF1  [traced]

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beedotman
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Post by beedotman »

New shit from Dunlop, yo!
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Post by sinner »

I wonder what is underside...

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Post by beedotman »

me too, but this component values could work without uderside trimmers, too... :)

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Post by sinner »

It's BC what? I know one of EJ's all time favorite ones is THE red one on BC183L. I can't see on the picts

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Post by phibes »

They look like BC183. Underside will probably look exactly like all their other Fuzz Face's with that board. You could easily generate a schematic from that pcb image.
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Post by sinner »

Tim, Joe Bonamassa's FF had few extra SMD components underside

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Post by beedotman »

sinner wrote:It's BC what? I know one of EJ's all time favorite ones is THE red one on BC183L. I can't see on the picts
BC183

It is inspired by EJ’s prized personal Fuzz Faces and is built to his incredibly strict specifications, featuring hand-selected BC183 silicon transistors (for higher gain), custom repro ’68-’69 knobs, and a vintage-style hammertone finish.


http://www.jimdunlop.com/product/eric-j ... -fuzz-face

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Post by beedotman »

Picture says BC183C, I think...

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Post by nightraven »

nice, i'm interested in trying this pedal out (if the price is right of course)
my favourite pedal ever is my grey Fuzz Face with BC183L transistors
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Post by Seiche »

Interesting, although talking about "designing the circuit" is a bit of a stretch with a fuzz face. Enclosure looks nice though.

Pots would 100kB and 1kB?

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Post by sinner »

I have 300-400 BC183L, and they're not higher than 350hfe, most of the cases 200-250hfe.

This makes them perfect to this application IMO

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Post by sinner »

Seiche wrote: Pots would 100kB and 1kB?

I'm not sure about that, but if I remember right - on Dave Fox website was an article about Crest Audio reissue FF's, it's gone now, I can't find it. Dave Fox said something about the mods of EJ's FF he done - he changed transistors to BC109c, he also changed bias point with 6k8 resistor, and also he changed the pot (or pots) to 2k. But like I've said. I lost this article, and I'm not sure any longer. EJ loved that, perhaps we have the pots changed here as well?

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Post by Seiche »

sinner wrote:
Seiche wrote: Pots would 100kB and 1kB?

I'm not sure about that, but if I remember right - on Dave Fox website was an article about Crest Audio reissue FF's, it's gone now, I can't find it. Dave Fox said something about the mods of EJ's FF he done - he changed transistors to BC109c, he also changed bias point with 6k8 resistor, and also he changed the pot (or pots) to 2k. But like I've said. I lost this article, and I'm not sure any longer. EJ loved that, perhaps we have the pots changed here as well?
i was under the impression that EJ prefers 100k volume pots, don't know about the fuzz knob, though.

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Post by Skreddy »

sinner wrote:I have 300-400 BC183L, and they're not higher than 350hfe, most of the cases 200-250hfe.

This makes them perfect to this application IMO
Yeah; no doubt BC183's back in the day were much lower average gain than today's. I have no idea if the transistors in the Dunlop are NOS or new though. If new, the "C" would make them insanely high for a typical Fuzz Face. --correction: just did a search on Mouser, and they're obsolete; so yeah, NOS (unknown year of course).

You can still get BC183L's and BC183A's made by CDIL, though. Will breadboard something like this to see for myself what works and how well.

sinner wrote:i was under the impression that EJ prefers 100k volume pots, don't know about the fuzz knob, though.
I know I prefer 100k volume; bigger creates impedance issues for things that follow.

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Post by Seiche »

Skreddy wrote:Yeah; no doubt BC183's back in the day were much lower average gain than today's. I have no idea if the transistors in the Dunlop are NOS or new though. If new, the "C" would make them insanely high for a typical Fuzz Face. --correction: just did a search on Mouser, and they're obsolete; so yeah, NOS (unknown year of course).

You can still get BC183L's and BC183A's made by CDIL, though. Will breadboard something like this to see for myself what works and how well.
http://www.musikding.de/advanced_search ... 83&x=0&y=0
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sinner wrote:i was under the impression that EJ prefers 100k volume pots, don't know about the fuzz knob, though.
I know I prefer 100k volume; bigger creates impedance issues for things that follow.
Hey I wrote that :D
Generally, me too, but what I found is that my range master sounds bad after fuzz faces with a 100kB volume pot. Much too harsh.

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Post by sinner »

Since I have my little stash, and in 5 minutes received 4 PM's about those transistors, here's the European source

http://markhindes.easywebstore.co.uk/BC183L_AHKPH.aspx

Mark still have more than 1000 of them :) I'm sure he have even more.

I remember when (2 years ago) I've found 30 online on his webshop, I've scored whole lot. To days later he added another 300pcs, and I've scored them all again.

The first bunch was different (marking, hfe range even lower 150-220), the ones I've both later had higher hfe range

Hope this helps

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Post by sinner »

Here's what the first lot looks like.

:)

I like them a lot, I wish I could have more of them. They took germanium FF bias resistor easily

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Post by Skreddy »

Played with some CDIL BC183A's and don't like them as much as BC109's. They've got a cardboard-ey, raspy sound, where the 109's are full & beefy. Maybe your trannies sound better, though.

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Post by Skreddy »

Seiche wrote:Interesting, although talking about "designing the circuit" is a bit of a stretch with a fuzz face. Enclosure looks nice though.

Pots would 100kB and 1kB?
I don't know about the aforementioned 2k pot mod (if memory serves that was a Roger Mayer mod?), but C1K is best for fuzz pots.

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