Seppuku FX Mind Warp

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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OH!STOMPBOX!
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Post by OH!STOMPBOX! »

i'll get up more info later.
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tabbycat
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Post by tabbycat »

nice gutshots, ohstompbox. your lit pcb underside traces especially good and will make this straightforward.

if you can get the small cap values or codes they would be useful as often tricky to read in photos, also the transistor code 2NXXXX (the one nearest ic will probably be the 78L05 regulator for the PT2399).
pot values useful too if you are able to undo them.

curiously i was listening to a casper electronics echobender demo (and checking out the layout) only an hour ago, which is another PT2399 and TL072 combo delay in the same low-fi warped delay sounds vein. may be related.

thanks for the post.

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Post by tabbycat »

pcb flipped so now viewed as from component side (led and ldr on right hand side of board, corresponding to component side views in original post).
warpspeed.jpg

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Post by tabbycat »

have added all the big bits and caps whose values i could see. if anyone wants to add the resistors you are welcome.
otherwise i will do a bit more later in the week as and when.
warpspeed bits copy.jpg
worth noting that on other mind warps i have seen there have been red or green leds, so i don't think the colour is critical.

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Post by OH!STOMPBOX! »

sisters moving so i've been/will be busy with that. the one tranny that can't be seen is just 2n5088 IIRCC.

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Post by DarrylC. »

man, I had full access to one of these a couple of years back. Took some pretty detailed pictures but I have no clue where they are. :scratch:


So, it is basically a pt2399 chorus that uses an led/ldr for the lfo. Are there any other chorus circuits that use a delay chip(pt2399 or bbd) with an led/ldr combo for the lfo's? I can't really think of one.

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Post by Nocentelli »

The Mid fi Pitch pirate is a delay with LDR+LFO controlled rate, but you can dial the delay time short enough to do chorus-y sounding stuff.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by Nocentelli »

mindwarp draft_nocentelli.png
A number of guesses were made
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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tabbycat
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Post by tabbycat »

neat schematic nocentelli. thanks for the post.
also meant to add these to the post last week but have had computer troubles. but here are a few more pics i found on the webs last year, i think. maybe these are darrylc's? they are big images, so chopped off on this page. but if you right click 'view image' on each you will get the whole thing.

i got what i could re big stuff from them re the layout i posted above, but they may help to clarify the reistors and other things which i hadn't got around to doing, so maybe worth the post.

Image

Image

Image

as well as the pitch pirate, maybe doug's (midfi) clarinot is another relation?

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Post by Nocentelli »

tabbycat wrote:neat schematic nocentelli. thanks for the post.
also meant to add these to the post last week but have had computer troubles. but here are a few more pics
Thanks! Different values in some places, e.g. input pull down is 820k instead of 1M, looks like the emitter resistor is actually 5k6 instead of the 1k i guessed at (hidden in the first set of pics), LFO resistor from non-inverting-> output is 47k in these new pics (so probably 39k in the first one) and it also has an additional 22 ohm in series with the 9v power.
tabbycat wrote:maybe doug's (midfi) clarinot is another relation?
I'm not sure if the Clarinot does a short enough delay time to get the same mangled chorus/hideous detune, but definitely a relation.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by DarrylC. »

tabbycat wrote:neat schematic nocentelli. thanks for the post.
also meant to add these to the post last week but have had computer troubles. but here are a few more pics i found on the webs last year, i think. maybe these are darrylc's? they are big images, so chopped off on this page. but if you right click 'view image' on each you will get the whole thing.

i got what i could re big stuff from them re the layout i posted above, but they may help to clarify the reistors and other things which i hadn't got around to doing, so maybe worth the post.

[ Image ]

[ Image ]

[ Image ]

as well as the pitch pirate, maybe doug's (midfi) clarinot is another relation?

I don't think those are mine. I can't remember if I ever put the pictures up anywhere, but if I recall correctly, the one I took apart was a black one. I had it out of the enclosure with the pot values exposed. It is a very stupid thing that I can't find those pictures. The store I work at was a dealer for a bit, we sold the mind warps we had but never got any new ones in again...

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Post by Nocentelli »

I breadboarded the schematic but with some changes informed by the pictures posted by tabbycat. The input and PT sections seem ok, but the signal from the BJT is a bit gritty I couldn't get the LFO to do owt.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by mictester »

Is it just me, or do all these Seppuku efforts sound completely unmusical? I've just spent almost 20 minutes listening to all the demos on You Tube, and there isn't any one of these pedals that I could use musically. I know there's a market for chaos and noise, but these things just sound horrible - unstable, unpredictable and unmusical!
"Why is it humming?" "Because it doesn't know the words!"

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Post by tabbycat »

thanks for the feedback on your experiments, nocentelli.

here's another mind warp pic i found at ilf last night, though rather smudged so maybe not v useful. appears to be the same unit (white case green led) as the others i put in my post.

Image

i think the op there is here too, under another name. will try to join the dots and fire him a message to see if he still has it.
Nocentelli wrote:signal from the BJT is a bit gritty I couldn't get the LFO to do owt.
the spacefuzz and octave drone both borrowed from escobedos (this is of that same period) so will browse the snippets to see if anything jumps out side-by-side with your schematic. maybe the pots are 1Ms or something unexpected?

by way of a benchmark, here's seppuku's 2009 demo video. sits between mbv and clarinot. shields on mandies. a lot to like.

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Post by tabbycat »

mictester wrote:Is it just me, or do all these Seppuku efforts sound completely unmusical? I've just spent almost 20 minutes listening to all the demos on You Tube, and there isn't any one of these pedals that I could use musically. I know there's a market for chaos and noise, but these things just sound horrible - unstable, unpredictable and unmusical!
i think it's a case of 'musical' is in the ear of the beholder, mictester. if you gave a maestro or tonebender to a classical violinist in the mid 1960s they may well have said the same thing. depending on whether they were coming from satie or schoenberg. ears acclimatise to the environment they are habituated to. people say if you live next to a waterfall you almost stop hearing it after a few years, your ears 'gate it out' after a fashion, so you can regain normal scope for close range hearing.
so if a musician's ear acclimatises to a 'noise' environment (listens to and plays 'noise' exclusively for years) maybe he/she hears through the 'noise' that the unacclimatised ears hear first, to the harmonics and textures that lay beneath, above or somewhere buried within it.

the random factor is also a thing. like eno's oblique strategies, or burroughs’ cut-up-technique. some musicians like a pedal that throws stuff at them they wouldn't consciously think to dial in. rather than impose any preconceived idea or intention onto the kit, they respond to what it throws at them. that's a bit of an art school definition (old habits die hard) but it might make some sense.

but from my experience, these sounds are the way things are going re the alternative mainstream. drone as a movement is getting bigger and bigger, which is a variety of manicured and manipulated noise, rather than music in the classic rock three-chords-turn-it-up tradition.
and pedal boards are almost becoming more important that guitars in many respects. they are increasingly becoming complete modular synthesisers by another name, and in many contexts guitars are gradually being subordinated to mere signal generators, responsible for just the first oscillation in a long signal chain. the tail wagging the dog? or a new dawn?

my impressions anyway. but i’ve read that when hendrix started, a lot of people (blues purists in particular) dismissed him as a gimmick man, all pedals and carnaby street tat, nothing of abiding substance. now he’s regarded as the touchstone of rock.

but the pedal boom should be good for your parts shop if that is still on the cards. musical and unmusical pedals all need bits.

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Post by tabbycat »

@ nocentelli. was looking at the modded doombutter over at madbean; clarinot plus cubed lfo plus feedback loop. all the elements are there.

relevant?
http://www.madbeanpedals.com/forum/inde ... pic=2694.0

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Post by Nocentelli »

tabbycat wrote: relevant?
Well, it features a pt2399 with an LDR wobbling the resistance to ground... but the feedback and the delay time pot going up to 100k mean that you will get a cascade of distinct actual echoes up to well over half a second and their pitch will wobble with the LFO and/or note note envelope. It looks more like a dirty echobase with envelope delay modulation. The mindwarp is a single short repeat, no delay possible.

Mictester - I wasn't particularly inspired by the demo's of the mindwarp, but having got a work-a-like going on my breadboard, i found you can get nice chorus and vibrato sounds using relatively few common and easily available parts
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by DarrylC. »

There is a possibility (albeit a small one) that I can get my hands on a mind warp within the next week or two. If I do get it in my hands, I will take the circuit out and take detailed pics of the board and pots. Hopefully those of you much smarter than myself can get a working vero layout out of it!

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Post by mictester »

Tabbycat: I understand what you're saying, and I fully appreciate what the "drone" and "noise" guys are about. I also appreciate some of the stranger and more extreme forms of metal (like some of the bizarre stuff coming out of Scandinavia), but perhaps I'm just too old - a few chords and turn it up loud usually works well for me! However, I have been known to use tuned feedback on stage.... but it's predictable and (most of all) it's musically valid.

In the same way, I have all sorts of issues with the use of ring modulators (they're never in tune!), and many other effects really don't do much for me. I think that it's quite funny that some boutique companies just turn out the same pedal over and over with a couple of changed values to "re-voice" it - and the gullible fools at TGP will buy each as something new....

I spent a little while examining the different types of distortion pedals out there, and found that there were only about five basic circuits and variants of these. I'm working at perfecting three of these for a line of pedals that should appear early next year if I can get the metalworking side of things sorted out (I have a case design that's a bit out of the ordinary, but has some mechanical advantages). I think that it's time to go more mainstream! I also want to get a really solid optical pedal mechanism working (a bit like the Morley ones, but better designed)......

As to the idea of a component shop - it's something I'm working towards - getting suppliers lined up, building test equipment to check NOS components for quality (and authenticity!), and working out the extent of the range of components that we need to stock.
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Post by DarrylC. »

ok, I got my hands on a mind warp and took a picture from every conceivable angle. I got a good shot of every resistor and every capacitor. I'll get to posting them tomorrow night when I get off work.

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