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Thursday, 3 January 2013

Memphis Distortion

When i first looked at the schematic, i thought that there isn't much point in drawing this - as it is very mildly modded Dist+/OD250 derivative. But then it occurred to me.. There is some psychological thing stopping me from modding a Dist+ or 250. Somehow those seem to be untouchables. So i drew this up to as a mind game, to be easier stop for modding :)

For starters, one should try different clipping diode options, such as 1N4148, LEDs, schottkys, multiple germ/Si/LED/schottkys in series - maybe put some of those combinations on a switch. The another thing i would suggest trying is to replace 1M feedback loop resistor for a pot. Plus there are tons of more things you could do with a simple distortion circuit like this. ...or you could just clone it.


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13 comments:

  1. atomicwombat5 January 2013 at 02:10

    you can tag this one. its verified. i played around with the diodes a bit. started off with some 1N270's. sounded just like you'd expect. very distortion+ sounding. LED's seemed too loud. i really liked the sound of pairs of BAT42's in series, and also 3 1N4148's asymmetrical. i'll play around some more tomorrow before i decide. this was my first build from a miro layout, and it went smooth and easy. kudos to you, sir, and keep up the good work!

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  2. Unknown6 January 2013 at 07:01

    what about resistor 68K? there's no line to connect....

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    Replies
    1. mirosol6 January 2013 at 09:55

      Well noted. Bottom lead to ground. I'll fix the layout.
      +m

      Delete
  3. atomicwombat6 January 2013 at 17:09

    thats odd. i built this and played around with it for a while, and it sounded good to me. then i saw that last post about the 68K missing a link to ground. i soldered in that link and didn't really notice any change in sound. i thought that it would have make a noticeable difference. odd.

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  4. Unknown29 September 2013 at 18:24

    Is the Schottky diode 1n5817 apart from polarity protection also used for biasing the ic? Because it is in series with the +9v. Or is it used because of the low voltage drop? Then i guess i can use a 1n4001 from +9v to ground (parallel instead of series).

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    Replies
    1. Unknown29 September 2013 at 18:27

      And if it is necessary for bias i guess i can use a BAT42 too? Because it also has a voltage drop of about 0,4. Am i right?

      Delete
    2. mirosol29 September 2013 at 18:29

      It's there as polarity protection only. And it is used because of the low voltage drop.

      Yes. You can.

      We always tend to replace parallel polarity protections with 1N5817 in series - as the latter way won't destroy the board when you give it the wrong polarity.
      +m

      Delete
  5. D_Pan9 June 2016 at 21:05

    How would I go about putting a switch for the clipping diodes? Thinking of using a DPDT or rotary to get more options.

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    1. mirosol10 June 2016 at 07:01

      Remove the two from the board and take wires from the strips those two were connected. Try a On-Off-On DPDT and solder those wires to switch lugs 2 and 5. Then solder back to back LEDs between lugs 1&4, and back to back 1N4148s between lugs 3&6. Now you have three different clipping modes - LED, Si and Lift.
      +m

      Delete
    2. D_Pan10 June 2016 at 11:56

      When you say back to back, you mean solder two LEDs/Si diodes on the poles? Or put them on a daughterboard?

      Delete
    3. mirosol10 June 2016 at 19:38

      Solder them straight to lugs. By back to back i mean that those diodes need to be soldered like this; anode of LED1 to lug 1, cathode to lug 4. Anode of LED2 to lug 4 and cathode to lug 1.
      +m

      Delete
  6. Unknown27 August 2016 at 16:17

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    ReplyDelete