Saturday 6 February 2016

Wyllie Moonrock

   This is a mysterious little octave fuzz that apparently has a very nice, dynamic sound. I looked for the original transformer and it isn't currently available at mouser. Try a TL018 and use the 10K side. Thanks to Cozybuilder, Dino, and the others that contributed to this schem at diystompboxes

   From what I've heard this will give the usual octave fuzzes a run for their money. Looks very interesting!



23 comments:

  1. Found 42TM012-RC here
    http://www.cpcares.com/xicon/Xicon_EI_19_Audio_Transformers/42TM012.html
    Dunno if the RC thing matters...also have never heard of this company either

    ReplyDelete
    Replies
    1. Thanks, Shane. I compared the datasheets and as far as I can see, the 42TM012-RC is just the RoHS compliant version of the 42TL012. So they should function identically

      Delete
    2. Nice layout Travis. So would any transformer with a one 10k coil winding would be suitable for this?

      Delete
    3. I'm not enough of an expert on this to tell you for sure Beaker, but when in doubt check the datasheets. I would think that in addition to the induction, the resistance and frequency range would also be important, but as I said I'm not 100% sure

      Delete
    4. Ok, datasheets checked, frequency range is the same across the range for these transformers, but resistance is nowhere near on the other 10k models.
      It's a shame as Useful Components here in the UK stock most of thse models, but not the 012's. They are a really good suppier of parts, so I emailed them to see if they can help. Fingers crossed!

      Delete
  2. This comment has been removed by the author.

    ReplyDelete
  3. NICE!! thanks goes out to CozyB and DiGi for reverse engineering this one! and thanks for the vero layout gfx !

    more in depth discussion on the moonrock:

    http://www.diystompboxes.com/smfforum/index.php?topic=108341.msg1046197#msg1046197

    ReplyDelete
    Replies
    1. lots of nice gut shots ...hello billy , its john from stl ..I know you are going to build this one lolol ..right up your alley billy !

      Delete
  4. Just built this and it sounds amazing!
    You can tag it as verified.

    I used a 42TM018 and 2N3904 as a substitute for the 2SC945.
    I tried a 2N2222 as well, but it gave lower volume and less pronounced octave.
    Will try a 2N5088/89 later today, to see if it increases volume/octave further...

    This is without a doubt the most pronounced octave up fuzz since Gus Smalley's Octave Up Sick Box (Also a highly recommended build. "Sick" is actually an understatement! It's insane!)
    This one goes straight to my pedalboard, replacing my Ampeg Scrambler!

    ReplyDelete
    Replies
    1. Thanks for verifying, Neil!

      Delete
    2. So you used a 2N3904 for Q2 Neil?

      Useful stock the 42TM018, so I will get one of those. Thanks for the heads up!

      Delete
    3. Yes, a 2N3904 for Q2 sounds great in my ears.
      When I looked up a substitute for the 2SC945, the 2N3904 was on top of the list.
      But I do suspect that other transistors might give better swells as mentioned by Travis below, so make sure that you use a socket for that position, so that you can experiment.

      I'm happy with it as it is now, but I also important to mention that I personally do not find the swell function very interesting, since it is not a feature that I need for my music/songs (yet...), so I leave it up to somebody else to judge if the swells are as they should be with the 2N3904 in Q2...

      I forgot to mention that the swells are at CCW position of the pot, and the swells disappear gradually as you turn the pot Clockwise. I do not know if this is the correct way, or if it should be the other way around...

      Delete
  5. Beaker, have you read through the DIYSB thread? Apparently Q2 is critical for the swell function. Really seems to be worth experimenting with

    I ordered x100 of the 2SC945 for $3 including shipping or something ridiculous like that

    ReplyDelete
    Replies
    1. That's what I was wondering. I have a couple of 2SC945 already, but I get more. Like you say they are dirt cheap.

      Delete
  6. Regarding using the 42TM018:
    Make sure that you flip it around 180, so that you are using the secondary side of the transformer instead of the primary side as indicated on the layout when using the original 42TL012

    ReplyDelete
  7. Right, you might not use the primary side if you are using a different transformer

    Cozybuilder told me that he's tried several different transformers successfully. He says any of the TL0xx range will work

    ReplyDelete
    Replies
    1. Thanks Travis. The TM018/TL018 is the 10k/10k (so 1:1 winding ratio) version so perfect for a transformer isolated ABY box). Seeing as the TLxx range is more or less identical versions of the TMxx range (just smaller), these should be good to go too. (They must be if Neil has used one),
      Neil, is there a reason why I should use the secondary winding? Just curious.

      Delete
    2. According to the spec sheet that I have of the TM018; the primary side is 7K and the secondary is 10K, so I used the secondary. But I suspect that the primary will function as well. Don't know if it will give a different flavour though...
      My guess is that the most important aspect of the circuit, is that it runs via a coil, and that the value is not the most critical part (based on Cozybuilders statement mentioned above)

      Delete
    3. I am looking for an affordable audio transformer to build an ABY box with phase toogle, buffer to do a wet/dry rig with 2 amps at the moment. Have you build an ABY with the 018 transformers? Ever since watching the video I linked below I fear that the box will suck out tone and since I am going for the Isolated amp as my dry-base tone that would be really bad.

      https://www.youtube.com/watch?v=mrKruIIVV8s

      Delete
  8. After some testing/playing, I suspect that the swell sensitivity could be a bit better than they are with the 2N3904 in Q2. (the octaves sounds really great though...)
    I get swells at the first 1/4 of the OFS pot with a low gain pickup, and almost half way up with a hot pickup. Beyond that it changes the flavour of the octave, making it more pronounced and a bit thinner as you get closer to maxed (there is also a slight volume drop when 100% maxed, but that seems logical from what I see on the schematic and how the signal flows trough the circuit)

    So it's back to the man-cave for further experiments for Q2
    More on how it turned out later today!

    ReplyDelete
  9. Ok, it is now later today, and I can report the following:
    It seems like lower gain transistors gives better swell range, a decent volume range and a good clear octave.
    Higher gain transistors gives less swell range (only at 1/4th of the turn), but higher volume and more extreme and hairy octave ala Ampeg Scrambler/Foxx Tone Machine.

    I tried about 20 different transistors and was most pleased with 2N2219A, 2N1995, 2N3053 and BC108 regarding swells (notice that these are all quite old NOS transistors). Some of them are a bit squashed when OFS pot is turned all the way clockwise (not swelling), but it gives quite a nice and long sustain.

    For now I'm sticking with the BC108 which gave me a nice result somewhere in the middle between good swells and a very clear and nice octave.

    Higher gain transistors became a bit too much for my riffed up Junior Kimbrough style of playing, but is great for my extreme pedal mayhem side projects.

    Hopefully this information will give you a good starting point for experimenting if you do not have the original transistor at hand...

    ReplyDelete
  10. Great sounding octave fuzz, one of my favourites. Found that replacing the 2SC945 at Q2 with a Hfe of 371 , with a BC107B at Hfe 280 gave a better octave in my build.

    ReplyDelete