Friday, 10 January 2014

Rick Holt Vibracaster

Moving on from the Valve Caster, and as recommended by Neil McNasty, here's Rick Holt's Vibracaster.
The tube components are very similar, but the Gain, Tone and Volume controls have been removed and components selected for unity gain and a simple LFO added.

There are lots of mods suggested for this on diystompboxes but I've just based this on the original schematic Rick posted for the 12AU7 tube.  The mods should largely be easy to implement if anyone wants to, it's a pretty simple circuit and even with a few extra rows or columns added it should still be 1590B friendly.

When someone builds it will they post a vid on youtube so I can add one to this post.  Ta! :o)



16 comments:

  1. Not the right spot for a general question I think but theres been a lot af great tube projects lately. So here goes - Does pin 9 of the tube (whether it be a 12ax7 or 12au7) have to be wired to ground ? Always ? Thanks Jim

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  2. No. Never ;-)
    Pin 9 is not used and should not be connected to anything.

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  3. Here is a cool little thing you could do with the Valve/Vibracaster:
    Instead of mounting your led beside the stompswitch, stick it in the center of the tube-socket and your tube will light up and look like it's glowing when you switch it on.

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    1. I think I read about a way to make LEDs light up slower. That would be a cool feature. Too bad I can't recollect how that goes or where I read it. (if at all. I have been known to just dream these things up...)
      Anyone?

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    2. I put a little 3mm LED down the centre of the tube socket as a power on and used a standard LED for bypass switch. Looks pretty coolio..

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    3. You can find information about turning the led on slower here: http://www.geofex.com/article_folders/millenium/millen.htm

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  4. Saturday I'm getting my 12AU7 tubes, and then hopefully I can verify this unles anyone else does it before. Any suggestions for subbing the BC547Cs? I assume the standard 2n5088s will do, right?

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  5. This one made up for my disappointment with the Valvecaster. I just popped in an old 12AU7 tube and I immediately got a nice smooth beautiful tremolo. This layout is definitely worth building.

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  6. Glad this is verified, how does it sound?
    Cheers
    Dave

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    1. Sorry, didn't realize I verified it. It sounds good. There are better tremolos on here, of course, but this one does have a nice warm "hump" to it that made it well worth boxing up for me. I'd day everyone needs one of these in their collection for a little something special.

      It REALLY shines with a nice low output humbucker. I just recently plugged my Gretsch Double Jet into it and lordy it sounds nice.

      Plus it looks fuckin sexy with a tube lit from the bottom. Never under estimate the power of "sexy."

      I need to play around with getting the led to pulse with the tempo so it'll look like the tube is flashing in time.

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  7. This comment has been removed by the author.

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  8. Just wired this one up, and I have a few weird things going on...

    "Spinning speaker" effect (producing sound on its own)

    Speed and Depth seem to work "together" and not very well independently.

    I'm getting better tone with 9V; 12V supply seems to "drive" this effect a bit, or so it seems.

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  9. again thank you for this great site, I have a 12AU7 and want to build this, but I have a silly question, because the resistors are of another color and not blue
    thanks for the help

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