Request: John Hollis’ Zombie Chorus

Time for a chorus layout! This is the Zombie Chorus designed by John Hollis, supposedly a cool sounding DIY chorus. Give it a try and let me know what you think 🙂

Update (27.10.2012): Layout has been verified as working, thanks to Derek! And reportedly without any ticking issues either.

Related Posts

15 thoughts on “Request: John Hollis’ Zombie Chorus

  1. I build this 3 times and its all work greatly, the only problem is there’s a loud pop sound when the switch 3PDT enggaged. I tried to add a resistor pulldown (100k on output and 1M on input) but the pop doesnt gone.
    Anyone can help me ?

  2. Hi Norman,
    Sorry to hear your MN3007 died. There’s more than likely a soldering or wring mistake somewhere. Check out the debugging section.

  3. Hi.

    My Chorus dosent work. The MN3007 is Blowing up and very Hot.

    9,01 8,61
    4,62 8,61
    5,42 4,33
    0,00 0,00

    can anywone Help me?

  4. Hello Harald,
    I just finished this project but it does not work. I double checked all the components and I tried to replace both the chips (mn3007 and cd4046). I can only hear the dry sound from my guitar and a little, inaudible LFO ticking in my amp (the speed depends on the rate pot). I’m stuck in a dead end.
    I took the following readings with my multimeter:
    9,25 8,84
    4,59 8,84
    5,56 4,62
    0 0
    Thank you for any suggestion.
    Greetings from Italy

  5. …and I replaced the 100k speed to a 300k, still got the fast reps at max, but can even dial in real slow. Sound better and more useful.

  6. I built this today and it works great, no ticking or strange noises in background. The only thing I wonder is what the modeswitch should do? =) Is there any way to slow the speed down?

  7. I’m not knowledgeable enough to tell you, but it definitely sounds like something isn’t working right. If you had another MN3007 you could swap to check if that solves it.

  8. I just built this project and I don’t get a ticking noise. I get a strange osicaltion noise in the background. Wondering if my mn3007 is bad. I used that chip in another project that had went bad. Any ideas?

  9. Hello Harald

    I figured out all the Ticking problem with LFO effcts

    The LFO unit should be placed as far as possible from the input and out put (and the connecting cables)

    I built CE-2, Zombie, and the taptation delay,

    All the ticks come from the interference of the LFO section with the passive components

    If there’s any one going to try the Zombie

    remember to make U3 (TL072) few centimeters from the jacks and the main input and out put cable!

  10. Thanks for you reply Harald,

    I’m waiting for the CE-2 vero now haha!

    Nice vero!

  11. Sorry, Submariner. I haven’t built this one myself and I don’t know much about it. I have seen circuit described as being noisy by design though.

  12. No reason you can’t make a layout as well! The more the merries 🙂 Besides, making the layout is half the fun.

Leave a Reply

Your email address will not be published. Required fields are marked *

Time limit is exhausted. Please reload CAPTCHA.