Dr Boogey opinion

[caspercody]

Thinking of building Dr Boogey, anyone recommend which version is better? I found the one from GM, and from the geocities page. Is there any sound clips?

Thanks

[anchovie]

Do a search on the forum and you should be able to find lots of info on the development of the circuit and the improvements that were made.

[MicFarlow77]

Hey CasperCody,

Here is a neat link that has a lot of info:

http://www.diystompboxes.com/smfforum/index.php?topic=61391.0

I use the gaussmarkov layout as it has all the best improvements to me.

www.gaussmarkov.net

These links are good starts....

Thanks,

Mick

[caspercody]

I actually made a pcb of the GM board this weekend, and ordered any parts I am missing from Mouser today. Hope to have it built this weekend. Do you know of any problems with the GM version?

[ralley]

I've recently built a Dr. Boogey using the Gauss Markov layout dated December 14, 2007 (http://gaussmarkov.net/wordpress/circuits/dr-boogey/). 

The only problem I had is my trim pots are very touchy - a tiny tweak that doesn't appear to move the trimmer causes the drain voltage to jump from ~2V to ~7V.  The trim pots are behaving like they are some sort of extreme log scale. Still haven't got around to investigating what the underlying issue is.

Once dialled in it works fine. Not a problem with the layout as I have a similar issue with a Professor Tweed I recently built.

I used 2x1M resistors in series for the 2M resistor, a 22pF ceramic instead of 20pF; a 4.7nF for the 5nF and a 27nF or 33nF (can't remember which) instead of 30nF.

Rob.
(Edited for spelling and layout)

[MicFarlow77]

I actually made a pcb of the GM board this weekend, and ordered any parts I am missing from Mouser today. Hope to have it built this weekend. Do you know of any problems with the GM version?

None that I know of and I have built a few of them based on a highly modified GM layout that I drew up to meet my own needs.

On the trim pots... if you order cheap ones, you may (most likely) will get some added noise in terms of high end hiss.... also, if you use multi-turn trims, you can get them dialed in real easy!

Good luck and post some sound clips when you have it finished!

Thanks,

Mick

[petemoore]

  I remember fiddling with dialing in those Jfets.
  Started with most of whatever using a pot to get a ballpark figure for R Drain.
  The put a fixed resistor as 'most of it', and a pot to 'push the last bit of R'...cause the dern wide range pots makes it like trying to sink a putted baseball in a golf hole.