Pages

Tuesday, September 1, 2015

King Dubby Delay

Here's a cool delay designed by Nocentelli posted over on FSB. Here's what he had to say about it over there:

Here's a variation on the deep blue delay; two PT2399 chips and a current mirror delay pot give around 2200ms delay, although beyond 700ms gets pretty lo-fi. There are two points where a momentary SPST can be used: Either to briefly connect the input to the delay input on select phrases (dub mode), or to bypass the repeats feedback resistor for self-oscillation on demand.





Note: I've recently found out the capacitor going from Repeat 3 to Osc Sw2 is 22n.

33 comments:

  1. que valor es el del capacitor con signo de pregunta?!????

    ReplyDelete
    Replies
    1. en ingles es mas fácil que te respondan! jejeje

      Delete
    2. gracias =) estoy entre armarlo o no armarlo. es confiable? funcionara?

      Delete
  2. hey men , what value is the component that is in the repeat 3 ? Thank you

    ReplyDelete
  3. Nocentelli didn't give a value for that capacitor. So your best bet is socket and experiment.

    ReplyDelete
  4. Hallo Dtgehring, could you tell us please what did you use for the misterious cap? 22n? Some other value? Thank you!

    ReplyDelete
  5. Replies
    1. Nocentelli didn't specify in his schematic, but I would assume 1N4148s

      Delete
  6. Greetings!
    I built this today. It's pretty awesome. Unfortunately, the OSC slam switch doesn't do anything. I was trying to figure it out, but I can't seem to get it to work. Maybe I need a normally open momentary switch for that one?.

    Also, I would love to be able to use the dub function but have it be switchable on/off so this could be used as a straight delay as well. I know it's probably really simple but my brain is farting on this one! Anyone know how I can do it?

    ReplyDelete
    Replies
    1. There's a new vero layout for this over at TagboardFX. Nocentelli posted this link:

      http://i80.photobucket.com/albums/j190/Leeroyfunk/dubby%20footswitch_zpsscycspeh.gif

      Thought I would share it here in case others are trying to add this switch scheme, and could use a visual aid.

      Delete
    2. I wanted to add an update. i pulled this out of the "semi-working circuits box" last night since I had insomnia. Anyway, here was what I figured out.

      I was able to accomplish all that I wanted, which was to have a regular bypass, with momentary Dub Switch and momentary OSC switch. I wired it exactly as nocentelli mentioned with the addition of a simple slam mod on the OSC switch. On the OSC momentary switch, I soldered two sockets (one on each pole). I put a 20k resistor on there for starters. Then I ran a wire from one pole of the momentary switch to lug 2 of the Repeats pot, and another wire from the other pole to lug 3 of the Repeats pot.

      It was a lot of trial and error, but I finally figured it out. Hopefully someone will find this info useful?

      Delete
  7. hi, where I can get schematic for this one?

    ReplyDelete
    Replies
    1. Added a hyperlink above that will take you to the original thread on FSB.

      Delete
    2. thank You very much.

      Delete
  8. Hi, what's a transistor with o g i pins?

    ReplyDelete
  9. Is there any way to add a tap tempo control?

    ReplyDelete
    Replies
    1. Not easily with 2 PT2399s. Maybe with some creative Arduino wizardry. But that's well beyond my knowledge level.

      Delete
  10. About the Transistors Q1 and Q2, what these values ? BC559S ?

    And the mysterious Capacitor ? 22nF ?

    What about D1 and D2? 1N4148S ?

    Has anyone recently built one of these ?

    ReplyDelete
    Replies
    1. Use whatever PNP silicons you have. And yes to the rest of your questions.

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

    ReplyDelete
  12. Good sound, Amazing delay !!!!
    Thanks

    ReplyDelete
  13. Works like a charm!

    Some advices for the builders:

    -The layout is amazing, but you must be carefull doing solder bridges, the pads and vias are too tight, a perfect iron temperature will be highly recommended.
    -The 16 pin socket will fit very, very tight. Only dual leaf contact types work. Turned pin contact socket won't fit.
    -The FX only comes alive when you close the "dub" switch. Must check the schematic for personal understanding of how it works.
    -True bypassing it won't do nothig, unleast you switch the "dub" pads, becouse it is the way you feed the PT2399's with your sound, otherwise you gonna listen your dry signal only.
    -The "osc" is a independent thing, wire it separated. I wired the "dub" together in a 6pole toggle switch and was a bad idea. For now, I ignored it.
    -Check your 1uF capacitors, my 1uF output capacitor was damaged and I could't hear the FX.
    -It has a lot drop voltage in the 33R resistor, to me was almost 2,5V but the circuit runs very well.
    -For the buffer I used LF353, and for the current mirrors I used BC560 just place it backwards.
    -For the 360k I wired two 180k in series.

    ReplyDelete
  14. anyone know of a good replacement for a 2N5087

    ReplyDelete
    Replies
    1. 2N3906 would this be an ok sub?
      https://www.onsemi.com/pub/Collateral/2N3906-D.PDF
      https://www.onsemi.com/pub/Collateral/2N5087-D.PDF

      Delete
  15. Hi there!
    I wanted to know if anyone have schematics for this great circuit?
    Thanks all!

    ReplyDelete