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Seppuku FX Space Fuzz

Posted: 10 Apr 2015, 01:04
by OH!STOMPBOX!
sounds just like his Ut00b, but this one has a really high noise floor. wondering if that's just the nature of the space beast?


either he's rolling back the volume on the guitar or someone must be turning down the pedal before bypass.

2N5088's, LM386N-1, 1N5817's?, not sure about the three diodes, hard to read. i'll post the pots and caps later.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 00:26
by tabbycat
i think seppuku described it as a modified version of the earlier seppuku octave drone when it first appeared. though website has changed a thousand times since then. but that's how i remembered it being described. may well be using some of the acid fuzz in there too, as it was the next fuzz he released after that.

the chaotic octave-bouncing feedback in this one may be a fingerprint that might help someone with a good ear for 'known things' place it. this is the most charcteristic demo i think, though it's dated a year after the one above and has different graphics, so may be an update, revamp or completely different thing. seppuku is a bit of an unkown/unknowable quantity and the website gets more minimal by the hour. but invariably interesting stuff.


thanks for posting, this is my favourite seppuku. it's immense.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 04:46
by tabbycat
useful? felt photoshopy.
spacefuzz pcb 1.jpg

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 11:41
by Nocentelli
OH!STOMPBOX! wrote:not sure about the three diodes, hard to read. i'll post the pots and caps later.
Excellent, I've traced the rest and will post a schem when I have those values. I'm guessing sustain is 1M, volume is 100k and all the yellow/orange multilayer ceramics are 100n (104).

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 13:27
by Moonsun
Trace this one too. Not shure about resistor values (i'm not good with colors). Waiting for tranny and diode values. I think it's based on Rambler, right?
Here's layout and schematic. Please do correct.
layout.png
schem.png
schem.png (2.46 KiB) Viewed 3887 times

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 15:09
by Nocentelli
860k? is 560k, LED clr is 1k2, your 68k is 6k8, not certain about the diodes' orientation into the 386, and R2 on your schematic (10k) should be in series with the sustain pot (which links base to collector, not to +9v), but otherwise that's what I've got.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 15:54
by Nocentelli
Ignore the R2 quibble, that's correct.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 20:32
by tabbycat
many thanks for the schematic and verifications moonsun and nocentelli. you're superfly, fast and furious.
re identifying the diodes, when i played around with the contrast etc i got the uppermost band ending in 7 and the bottom ending in 6.
am guessing that could be 1n5817 but don't know what the 6 in the bottom band means. 16v? manufacturer code? mark of the beast? anyway the 1n5817 i have are marked DC in the bottom band, no numbers. may click with someone.
also tranny markings just visible in the bottom one, though rubbish angle and probably not very useful.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 22:22
by OH!STOMPBOX!
pots are both b100k. looking at diodes again, be back.


104, C2 104, C3 333/333, C4 104, C5 104. and the 22k across the vol.

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 23:07
by OH!STOMPBOX!
yes, that's a 560k :thumbsup . diodes are both 1n5817, 616. germanium diode, can't see :shock: ?

Re: Seppuku FX Space Fuzz

Posted: 11 Apr 2015, 23:18
by Moonsun
Nocentelli wrote:860k? is 560k, LED clr is 1k2, your 68k is 6k8, not certain about the diodes' orientation into the 386, and R2 on your schematic (10k) should be in series with the sustain pot (which links base to collector, not to +9v), but otherwise that's what I've got.
Thanks! As I said I'm not good with colors (damn this color blindness). Diodes orientation is a riddle. One of the diodes definitely (well, at least as I see it on the third pic) goes anode to 386' leg 3. From the first pic I saw that other diode's cathode goes to leg 2, but I cant see it on the other pics... Anyway this stage reminds me of stripped off Tim Escobedo's Rambler, but Rambler's diodes goes in opposite direction. Think we need to breadboard at least this stage to make sure.
Ok, here is new version of layout and schematic with Nocentelli's corrections and additions from OH!STOMPBOX!
Seppuku Space Fuzz layout v0.2.png
Seppuku Space Fuzz schematic v0.2.png
Seppuku Space Fuzz schematic v0.2.png (3.64 KiB) Viewed 3810 times

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 00:13
by OH!STOMPBOX!
looking at the PCB, i think you've got diodes right.

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 00:45
by B3ar
In the board layout, all the voltage comes through that 100r--the +9v point on the schematic is after that resistor.

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 00:52
by tabbycat
@moonsun thanks for the quick update to the schematic.
re the transistors, the first post in this thread mentions 2n5088 but the schematic has them as 2n3904.
are the 2n3904 being subbed as a starting point for experimentation or a workalike for the 2n5088?

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 01:26
by tabbycat
btw, the first pics i've seen on the webs of a seppuku octave drone pcb appeared on ilf tonight. i mentioned above that i read somewhere (the seppuku site a year or so ago, i think) that the spacefuzz grew out of the acidfuzz, and this has a similar diode thing around the chip (unkown) and generally (to my untrained eye) resembles the 386 half of the space fuzz. at first glance at least.
seppukuoctavedrone2.jpg
but that idea may support moonsun's hunch that this is a game of two halves, the first half being a mutant escobedo rambler.

could it also be related to the fuzzhugger phantom octave?

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 09:01
by Moonsun
Ok, I breadboard it. 386 stage IS a Rambler. I use 1N5818 instead 1N5817 and 68 nF cap instead of 2 parallel 33nF. Sounds just like the video. And noisy as in video too )
As for trannys - I tried 2N5088, 2N3904 and 2N2222 for both 3 with almost same result and like 2222 mostly for lowest noise and more structured sound.
Make final (I hope so) corrections to schematic and layout. Here it is.
Seppuku Space Fuzz schematic v0.3.png
Seppuku Space Fuzz schematic v0.3.png (4.32 KiB) Viewed 3772 times
Seppuku Space Fuzz layout v0.3.png
Seppuku Space Fuzz PCB v0.3.pdf
(8.87 KiB) Downloaded 118 times

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 09:41
by d312a
Moonsun wrote:Ok, I breadboard it. 386 stage IS a Rambler. I use 1N5818 instead 1N5817 and 68 nF cap instead of 2 parallel 33nF. Sounds just like the video. And noisy as in video too )
As for trannys - I tried 2N5088, 2N3904 and 2N2222 for both 3 with almost same result and like 2222 mostly for lowest noise and more structured sound.
Make final (I hope so) corrections to schematic and layout. Here it is.
Seppuku Space Fuzz schematic v0.3.png
Seppuku Space Fuzz layout v0.3.png
Seppuku Space Fuzz PCB v0.3.pdf
Great! :applause:
Vero is in the works, I will hopefully post it later today.

Re: Seppuku FX Space Fuzz

Posted: 12 Apr 2015, 15:12
by B3ar
Go team!

Re: Seppuku FX Space Fuzz

Posted: 13 Apr 2015, 03:57
by tabbycat
the guts of the seppuku octave drone. seems to bear an uncannily strong resemblance to the escobedo rambler side of the spacefuzz. 2n5088 and 1n5817.

Image

Image

Image

it would seem that spacefuzz = rambler/octave drone + huge gain fat fuzz, which is why i thought this might be to do with it. seppuku was making these at the same time: seppuku fuzz overloader thread https://www.freestompboxes.org/viewtopic.php?f=7&t=26047

the owner of the octave drone is looking to get into diy building so may join here soon. i've told him this forum is the centre of all known wickedness in the universe, and i think he's tempted.
he's also offered to take more detailed photos of his drone if anyone wants to see it in its own tracing thread.

anyway, i've posted it here for now as there seemed to be uncertainty about the orientation of the diodes around the ic pins of the spacefuzz, and i thought these are pretty clean detailed pics of another seppuku with the same root (i think) which may help decrypt that.

Re: Seppuku FX Space Fuzz  [traced]

Posted: 13 Apr 2015, 09:07
by d312a
I'm not sure how to post pictures at this forum yet but I posted at verified vero over at Tagboard Fx's forum:
http://guitar-fx-layouts.42897.x6.nabbl ... fuzz_1.png

Sounds great, just like the clips online. High gain trannys make it a bit noisy, lower gain reduces the noise but also sustain. I prefered a 1N4148 diode instead of a Ge next to Q3.