is THIS the Shin Ei you typed about ?

[petemoore]

http://members.fortunecity.com/uzzfay/fy2/fy2.html
  I read a whole lot of 'fierce 'n flowery' language about some kind of Shin EI circuit is supposed to be a fiercely fuzzy sounding circuit.
  ....I've been having non-plussed experiences with this one, less than unity, kinda weak and splat-phase-removed sounding instead of fuzzy.
  Is there some other Shin EI that fits all the feirce 'n flower language or what ?
  Gus kindly suggested the Foxey Lady which has similarities, and looks like it might work, by 'work' I mean sound fuzzy and easily exceed unity volume.

[Mark Hammer]

That's the one.  It is VERY fuzzy (you can play all the Electric Prunes and Strawberry Alarm Clock tunes you want on it), and while it loses some volume because of the scoop filter, it is still quite capable of more than unity without having to max everything.

I have an original and have made a couple of clones using freshly-minted 2SC536 trannies, and they work out fine.

Where the problem is with yours, I have no idea, but I am confident that it will end up being a forehead-smacker (as in "Aw, JEEZ, man....stoopid, stoopid, stoopid!") in the final analysis.

[petemoore]

  Always [generally speaking] has...
   Maybe I'll try building one, this is one of those paper-stamp sized boards, seems debugged enough though, resistances wise.

[Mark Hammer]

When it comes to all-discrete circuits, I am the very last person to start monkeying around with bias voltages. I just stick the parts in that it says to stick in.  And in this instance, they work.  Did I simply get lucky?  Maybe, maybe not.

[petemoore]

  well, who even ever really knows...could be a fierce fuzz still I suppose.
  could be a bad capacitor or I misread one of the resistances a buncha times, seems like all the continuities and resistance are as shown [re: close by decision].
  Nothing can really be done for it beyond reading the almost correct resistances in it [I used a 1meg instead of 1m2, 2 x 1 meg for 2m2] a few more times.
  Seems debugged enough, .76V is quite small for an output transistor IME, this is where my circuit probably is weak, must be nothing or the old capacitor.

[SpencerPedals]

I had it on my breadboard for a good month or so playing with it every so often...it was fuzzy that's for sure...but as Mark mentioned in another thread, anything you do to mod the circuit makes it extremely different sounding and in the end, something else.  So I did what any sensible DIY'er would do and came up with a way to stick everything on a switch   

[petemoore]

  Has a bit of wool to it, and a bit of...harmonic richness...or Superfuzz-type undertones.
  I'll probably stick a booster on the end of it and call it a Fuzzy box.
  It's basically debugged I guess, .76v on Q2 is rediculous amount of play to start off with, for working an output, guess that's the idea, dunno how I could get it any higher without altering the circuit/bias.

[Gus]

Mark
Did you use  2sc563's with the G Hfe rating of 280 to 560? (H is 480 to 960)
  If I did the math right the stage with the 22K collector R and 2.2 meg base to collector and wanting the collector to be at about 2VDC I got a Hfe of 485

[Mark Hammer]

The originals (which I've already unsoldered a couple of times already, so I don't want to do it again) were in the 250hfe zone.  They have an E-C-B pinout, NOT E-B-C.  The C536Fs I bought more recently, that I used to make clones with all the gnarl of the original, have hfe in the 180-220 range.  So, nothing particularly special.

If you insert the mid-scoop lift control (5k pot between the .1uf cap and ground), you can increase the output level even more.  Ligfting the mids gives a wonderful chewy sound.

[Gus]

Thanks.  What I was thinking was if we note the Hfe and transistor numbers and measure the in circuit supply, base and collector voltages the circuit might become more reproducible.  Can you measure the supply, base and collector voltages on the builds you are happy with?

[petemoore]

  Pretty much has to be 'right'. Clean traces, verified connections and resistances, could be, I really doubt it's a miswire though.
  Works better with the RS 2n2222's I bought, those 60Hfe tinhat types don't have enough uumph to get the circuit to light up, I left in the 'low' 2n2222's about 240Hfe ones, instead of putting back in the 'over 300hfe' ones, no difference there.
  It's fuzz sound but not what I'd call fierce, the 'other' knob is cool, and the basic timbre of the pedal is kind of mild, I haven't memory enough of sound clips to say a comparison of what I'm getting.
  It does sound pretty cool, just above unity.
  Perhaps I'll just update it to the GGG version with the 2n3904 end-boost.

[drewl]

Sounds like you built it right, that's just the way it is.
I had bias trimmers on mine, tried a bunch of known great sounding transistors and it was still underwhelming.
For it's day I guess it fit the bill.

[gigimarga]

  Pretty much has to be 'right'. Clean traces, verified connections and resistances, could be, I really doubt it's a miswire though.
  Works better with the RS 2n2222's I bought, those 60Hfe tinhat types don't have enough uumph to get the circuit to light up, I left in the 'low' 2n2222's about 240Hfe ones, instead of putting back in the 'over 300hfe' ones, no difference there.
  It's fuzz sound but not what I'd call fierce, the 'other' knob is cool, and the basic timbre of the pedal is kind of mild, I haven't memory enough of sound clips to say a comparison of what I'm getting.
  It does sound pretty cool, just above unity.
  Perhaps I'll just update it to the GGG version with the 2n3904 end-boost.

Glad you here it's right...can you post the voltages now?
I am very curious if GGG's are right or not...

[petemoore]

  Q1
  C 2.56
  B   .46
  Q2
  C  .76
  B   .56
  Emitters grounded.
  Sounds pretty cool, but the low notes make 'buzzbox' tones [kind of outstanding/slightly annoying...like 'blips' added to the wavepeaks.
   .76v doesn't seem like an 'optimal' place for an output Q's C to settle...right inbetween two walls that it slams in to every time it moves more than really small movements.
  Perhaps I diddle with it some more or try a Foxey Lady, which looks at least loosely related.

[Mark Hammer]

Scroll to the bottom of the page here:  http://hammer.ampage.org/?cmd=lt&xid=&fid=&ex=&pg=12
You'll find a soundclip and an explanation of the soundclip.

[gigimarga]

  Q1
  C 2.56
  B   .46
  Q2
  C  .76
  B   .56
  Emitters grounded.
  Sounds pretty cool, but the low notes make 'buzzbox' tones [kind of outstanding/slightly annoying...like 'blips' added to the wavepeaks.
   .76v doesn't seem like an 'optimal' place for an output Q's C to settle...right inbetween two walls that it slams in to every time it moves more than really small movements.
  Perhaps I diddle with it some more or try a Foxey Lady, which looks at least loosely related.

Thx petermoore!
My voltages are almost tha same as yours.
Foxey Lady it's amazing...give it a try!

[gigimarga]

  Q1
  C 2.56
  B   .46
  Q2
  C  .76
  B   .56
  Emitters grounded.
  Sounds pretty cool, but the low notes make 'buzzbox' tones [kind of outstanding/slightly annoying...like 'blips' added to the wavepeaks.
   .76v doesn't seem like an 'optimal' place for an output Q's C to settle...right inbetween two walls that it slams in to every time it moves more than really small movements.
  Perhaps I diddle with it some more or try a Foxey Lady, which looks at least loosely related.

If i remember well Radiohead have 2-3 Shin-Ei stompboxes...they use it on bass on some songs.

[gigimarga]

Scroll to the bottom of the page here:  http://hammer.ampage.org/?cmd=lt&xid=&fid=&ex=&pg=12
You'll find a soundclip and an explanation of the soundclip.

Mine sounds almost as in your clip...but i'm still waiting for the voltages 

[petemoore]

  Much Fiercer than mine sounds Mark, many of the same characteristics though.
  I'm going to stuff some more resistors in mine and try out more of a Foxey Lady type circuit.