SEEA - Fuzz Stereo  [schematic]

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VitaliiBobrov
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Post by VitaliiBobrov »

SEEA Fuzz Stereo, made in Poland, my unit pots dated 1989.
Front
Front
Seems no info about this one except Effects Database (https://www.effectsdatabase.com/model/seea/fuzzstereo) and mention in one of JHS Show episodes. My unit had a mess with wiring inside made by the previous owner, so I decided to trace it while fixing it. Basically, it follows Distortion+ topology (values are modified a lot), then Big Muff tone stack and gain recovery stage with signal splitting for stereo.

Schematic, not 100% that it is correct (especially stereo switch and output filtering) as it was my first time tracing something:
seea-fuzz-stereo-v3.pdf
Schematic v3
(75.81 KiB) Downloaded 110 times
Gutshots:
PCB
PCB
PCB
PCB
BOM:
IC: NS TL082
D1, D2: Ge AAP158 (NOS I have measured around 400mV)
D3: 1n4148
D4: Red LED 5mm
D5: 1n4001
R1: 1M2
R2: 100k
R3: 10k
R4: 1M
R5: 100k
R6: 220k
R7: 910R
R8: 4k7
R9: 4k7
R10: 8k2
R11: 1M
R12: 1M
R13: 47k
R14: 100k
R15: 10k
R16: 10k
R17: 10k
R18: 10k
R19: 10k
R20: 4k7
R21: 1k
Pots Dist, Tone, Volume: A10k
C1: 18n
C2: 470p
C3: 330p
C4: 1u
C5: 4u7
C6: 150n
C7: 220n
C8: 100n (polarised)
C9: 47u
C10: 330p
C11: 470n (polarised)
C12: 1u
C13: 68n
C14: 47n
C15: 47n
C16: 47n
C17: 10u
C18: 330p
C19: 330n
Attachments
seea-fuzz-stereo-v2.pdf
Schematic v2
(75.7 KiB) Downloaded 156 times
seea-fuzz-stereo.pdf
Schematic
(75.8 KiB) Downloaded 167 times

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Jarno
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Post by Jarno »

Interesting, so the only thing making it stereo is a bit of highpass/lowpass?
"It crackles....., but that's ok"

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VitaliiBobrov
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Post by VitaliiBobrov »

Yes, seems just splitter and filtered differently

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Post by lcv »

Vitali,
In general how does it sound?

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Ben N
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Post by Ben N »

Stereo seems an odd thing to add to a basic distortion. Was that some kind of marketing fad in Poland c. 1989?

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VitaliiBobrov
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Post by VitaliiBobrov »

@lcv, Not bad - it doesn't have a lot of gain, but give crunchy/fuzzy vibe, tone control is pretty usable across the full range. Diodes clipping switch makes a pretty subtle difference (is just replaces Si diode with lower Vf Germanium one).

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VitaliiBobrov
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Post by VitaliiBobrov »

@Ben N - not sure, but to me it's more marketing as well, rather than usable feature. This thing doesn't seem to be very popular as I haven't seen it before and there is almost no info about both brand and pedal.

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Post by snk »

It looks nice, I like that switch :)

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