Pages

▼

Tuesday, 25 February 2014

Mid-Fi Electronics Demo Tape Fuzz

Request.  Info about the original which I think is a great sounding fuzz:

created to recreate the sound of a guitar playing directly through a 4-track cassette recorder, the Demo Tape will bring you back to your 4-track days. spatty supersaturation and harsh to thick and full, the Demo Tape comes equipped with a two band EQ, volume and trim for simple, versatile and practical tonal shaping. four controls are Bass, Treble, Volume and Trim.






at

56 comments:

  1. Piltdown Man25 February 2014 at 13:35

    This sounds cool, what IC is that?

    ReplyDelete
    Replies
    1. IvIark25 February 2014 at 13:40

      Weird, I added the IC text but must have cropped it off the bottom or something. I'll add it now. JRC4558 by the way :o)

      Delete
  2. Unknown25 February 2014 at 14:01

    The demo sounds too good to be true, had anyone tried this pedal yet?

    ReplyDelete
  3. Scott25 February 2014 at 15:54

    Reminds me of overdriving my Yamaha 4 track. The guy in Medicine is famous for using that same overdriven Yamaha 4 track as his main tone, both in the studio and live on stage. I saw them play once and there it was sitting on his amp and the LEDs were pegged in the red. I wonder if this circuit was taken from a specific preamp on a specific tape deck or just made up to sound like it...

    ReplyDelete
  4. tunatuk25 February 2014 at 17:34

    I'm definitely gonna build this one tonight! That demo is incredible, and as long as it gets 3/4's as good as it, I'd be happy with it! I might even work on making my first pretty enclosure for this one!

    ReplyDelete
  5. Kinski25 February 2014 at 22:21

    Just built this. Sounds amazing! Cleans up really well with the volume knob. Tag it!

    ReplyDelete
  6. chumbox 26 February 2014 at 01:17

    What a great sounding pedal. Need to build this. Thanks for the layout!

    ReplyDelete
  7. chumbox 27 February 2014 at 03:41

    Any chance of the schematic location?

    ReplyDelete
    Replies
    1. IvIark27 February 2014 at 07:57

      FSB thread

      Delete
    2. chumbox 27 February 2014 at 08:28

      Of course! What was I thinking :)

      Delete
    3. Beaker27 February 2014 at 19:49

      Just built this this up and it sounds like it might be my perfect fuzz. The tone stack is really good, with loads of great tones available. High gain is good, but it's right down the other end of the gain knob where this thing really shines.

      If you are looking for a pedal to get great Lo-Fi Pavement style tones, or are a fan of The Gun Club or anything Alt-Country, you NEED this pedal.

      Just one issue though - mine is insanely loud. I don't think I have made a mistake anywhere, but I get unity gain at about 8 O'clock on the volume pot. Anyone else's build hve the same issue?

      Delete
    4. Anonymous30 March 2014 at 11:30

      Where's the FSB thread? Sorry, new here!

      Delete
    5. IvIark30 March 2014 at 12:33

      http://freestompboxes.org/viewtopic.php?f=7&t=23077

      Delete
  8. nocentelli27 February 2014 at 20:18

    I think that's normal. I used a log pot instead of linear for volume and treble, and a log taper means the most useable settings are closer to 12 o'clock.

    ReplyDelete
  9. Beaker27 February 2014 at 21:14

    Thanks for that nocentelli, I will give a log pot a try.

    ReplyDelete
    Replies
    1. Beaker1 March 2014 at 17:16

      This comment has been removed by the author.

      Delete
  10. johnk1 March 2014 at 09:20

    I built this one the other day. I like the tone stack, but for me, its distortion isn't my cup of tea. i'm generally not a fan of opamp distortion, and this one reminded of that.

    ReplyDelete
  11. Unknown9 March 2014 at 05:56

    Built this the other day . It's very cool pedal. 3 row span resistors are a pain and some of the caps were very tight but it was a successful build. I etched an enclosure and boxed it up. This was my second pedal. The text is black but on the picture it looks purple. I wanted to have it look like handwritten labels like the old tapes but next time i am going to just etch the labels too. http://i.imgur.com/7ziOXv1.png

    ReplyDelete
  12. Unknown4 May 2014 at 16:00

    i just built this and i have a strange problem, everything is working except the gain. the volume, treble, and bass work but the trim is just acting as a second volume control. any idea what would cause this? i've gone over everything a couple times and everything seems to be in the right place and nothing is being grounded out that shouldn't be.

    ReplyDelete
    Replies
    1. Rose19 July 2014 at 14:05

      Did you find the solution to that problem?

      Delete
  13. Rose18 July 2014 at 16:33

    I need some help...where is the output??? Thanks!!!

    ReplyDelete
    Replies
    1. Rose18 July 2014 at 16:34

      And trim 1? I almost finish building it

      Delete
    2. IvIark18 July 2014 at 16:40

      The output is shown in the notes. The Trim pot is used as a variable resistor so only two lugs are needed. You could link 1 and 2 if you want but it isn't necessary.

      Delete
    3. Rose18 July 2014 at 16:43

      thanks a lot!!!

      Delete
  14. Unknown16 August 2014 at 02:53

    How can I connect a DPDT switch? Is this correct? http://www.guitarristas.info/foros/enseno-como-conectan-switch-3pdt-dpdt-identifi/226119

    ReplyDelete
  15. RareDevil17 October 2014 at 09:00

    Yes it is the same as here.

    http://tagboardeffects.blogspot.hu/2014/01/millennium-bypass-2.html

    ReplyDelete
  16. Fuzzdog17 May 2015 at 10:58

    Do you reckon a tl071 would make an overly huge difference?

    ReplyDelete
    Replies
    1. Fuzzdog17 May 2015 at 11:06

      TL072**** Further reading, I found out most of the newer versions of this pedal have TL072's. Just in case anyone else was wondering!

      Delete
    2. Beaker17 May 2015 at 11:54

      Yeah, I've used both chips on this - I prefer the TL072 myself.

      BTW are you Fuzzdog of Pedal Parts UK fame?

      Delete
    3. Fuzzdog18 May 2015 at 00:11

      Nope, never heard of him/her! May have to change it!

      Delete
    4. Unknown2 February 2016 at 00:58

      in case you use a TL072, would the components change? I have one here but I must admit that I am a newbie.. just built one pedal yet.

      Delete
    5. chumbox 2 February 2016 at 03:22

      Hye guilherme Ri, nope the parts will stay the same. The JRC4558 is a dual opamp (has two channels), so any dual opamp will in theory work such as TL072, NE5532 or if you want to blow some dollars on 'mojo' try a Burr Brown OPA2134PA. You may find they change the sound in slight ways, or in the case of TL072 it may actually reduce some noise (if that's what you are looking for). Best thing to do is to socket the IC and just try a few dual opamps in there. JRC4558s have a perceived ol' school mojo factor and appear in a lot of pedals, but you can change 'em. Have fun!

      Delete
  17. Fuzzdog18 May 2015 at 08:55

    The top left link is in the wrong spot in the links and cuts picture.

    ReplyDelete
    Replies
    1. Ciaran Haslett18 May 2015 at 19:15

      It is but only requires a small shuffling of resistors. The connections themselves are unchanged

      Delete
    2. Fuzzdog19 May 2015 at 12:54

      Wouldn't you just move the link over one to make it the same as the component layout?

      Delete
    3. Ciaran Haslett19 May 2015 at 18:41

      You could, and I'd do it too but I tend to do cuts and links first (work from lowest components to tallest components) so I would probably have put the link in the position shown on the bottom pic before realising its not the same on the top. It would be a bit of a surprise but nothing you can't work around.

      Delete
  18. Unknown18 March 2016 at 04:48

    I´ve just got an empty 1590b Rockett "blue note" enclosure and a bunch of 4558 variants, so this seems like perfect for it.
    The enclosure has 4 holes for pots and one for a switch, so any idea of what I could switch inside the circuit? Maybe a couple of diodes on a smart place...

    ReplyDelete
  19. Unknown16 May 2016 at 09:13

    I know this is an old thread, but thought someone could point me in the right direction.. Fuzz sounds great, I love it but the trebles and bass controls do nothing. I have used resistors in series to get close to the correct values for the 10Ks and 3.6ks. So in my build the 3.6k is ~3.69k and the 10K are ~10.2K. Is this going to be the problem? Or should I look for something else? Thnaks in advance and thanks for a fantastic site!

    ReplyDelete
    Replies
    1. rickst17 May 2016 at 17:10

      Hi, I don't think the resistors in series is a problem at all, and being less than 5% off with any of the resistors should not make any noticeable difference. I'd say it's something else. I guess, try double checking the pot wirings. One problem I often had often is accidentally making tiny contacts between tracks when soldering the wires. Hope it helps

      Delete
    2. Unknown19 May 2016 at 10:41

      Thanks a lot for your reply. I had checked those things but then realised I left out a resistor. duh! Slightly embarrassing. I agree with your post below, I was hoping to get it a little more Lo-fi but I love it anyway.

      Delete
  20. rickst17 May 2016 at 17:04

    Awesome pedal! Sounds crunchy and slightly broken down. What really shines is the separate Bass knob that can make it much fatter. You can dial some very familiar tones. The Trim knob can push a big distortion, which is cool, but I expected it would control the lo-fi'ness instead. Anyway, well worth building, it's really one of my favorites now.

    ReplyDelete
  21. Unknown5 December 2016 at 19:29

    Aha, I used to use my Tascam 4-track for distortion too! Great idea to put it in a pedal. One question -- if I'm using tantalum caps for the 1U values, which way do they face? I tried to track the paths back from ground, but want to be 100% sure. Thanks.

    ReplyDelete
  22. Unknown10 December 2016 at 06:03

    Got it working with help in the forums! For the record, my leftmost 1u cap is oriented positive on the bottom, and the other two are positive on top.

    ReplyDelete
  23. pakkee6629 March 2017 at 17:16

    I played the guitar till to pain on my finger during board test, what the great fuzz sound~ thank you very much for the layout and this circuit designer.. here's my board share: http://i1244.photobucket.com/albums/gg569/pakkee66/DIY%20PEDAL/Mid%20Fi%20Demo%20Tape%20Fuzz%20CB_zpsjdpynl9d.jpg

    ReplyDelete
  24. lowlevelowl9111 June 2019 at 07:02

    Built the circuit as pictured in the very layout a ways back and I love everything about it - except the volume pot. Everything is WAY TOO LOUD. What's the best way to attack this problem considering the pedal is already a finished product boxed and everything? Solder a resistor somewhere on the volume pot lugs? Use a different value volume pot?

    ReplyDelete
    Replies
    1. Eli_Klngsmkt9 January 2020 at 06:01

      I would try a log pot instead of lin. Most of the time I don't get why lin pots are used for volume.

      Delete
  25. Eli_Klngsmkt15 January 2020 at 00:21

    The next entry in my collection of pedals I built because this blog made me obsessed :-D

    Not too fuzzy but has a nice and interesting character to it. Definitely stays boxed.

    Thanks for the layout!

    ReplyDelete
  26. Rod17 April 2020 at 04:07

    hey, how does the circuit compares to the opamp big muff (like, if you take the lm741 section out of the equation)? they share 4558

    ReplyDelete
  27. Ben Spinks9 November 2020 at 19:46

    This sounds great, but gain is only really happening in the last 10% of the gain knob. Is this normal?

    ReplyDelete
    Replies
    1. Eli_Klngsmkt2 December 2020 at 17:01

      I think so. One could try a reverse log pot for Trim.

      Delete
  28. Fredrik Fencke30 May 2021 at 05:12

    Has anyone tried different tapering on the trim/gain pot? There's a lot happening at the very end of the sweep, and I would like to spread it out more evenly. I don't have any reverse-log pots on hand, but maybe that will work?

    ReplyDelete