build report: Dr boogie[boogey] [gm layout]

[km-r]

hi all!

its my third build though... my second build was fine [gm layout too] (first build wasnt successful) but the recent great flood by typhoon frank/fengshen got my pedals burried in mud. then i was forced to borrow pedals for gig/personal until recently decided to build another DB.

i still have my issues though. all my DB builds squeals with other guitars... my guitar is equiped with a DIY fet preamp that maybe eliminates crappy cable effects... http://www.till.com/articles/GuitarPreamp/
is there any other way i could fix this? i dont want my DB to be an exclusive to my guitar.

bias is set at 4.5v with regulated psu.
i wanted the highest gain possible so i modified some of the voltage dividers along the circuit, another mod i did was to lower the bypass cap of the first J201 to 0.22uf and used a 4n7 for the top cap on the tonestack.

at first i thought the DB is good with vanhalen-ish or 80s metal as i was not very tweaky with the tone knobs. but recently i tried tweaking for some blackmetal tone... wow... i didnt know my DB! its got a nice down n dirty sledgehammerish attitude!

heres a quick n dirty clip, full gain, through a marshall condor cab sim. added software reverb.

http://www.imeem.com/people/GRjTZVJ/music/Ur4-m0t_/taak_mixdownmp3/

[rogeryu_ph]

Km-r,
That's a great sound man 
You still got the same issue once more with this new built? Well for sure no one could borrow your DB 

Ciao,
Roger

[frokost]

There was a very informative post a little while ago about the boogey and squeal as a result of no buffering.

http://www.diystompboxes.com/smfforum/index.php?topic=71019.msg572435#msg572435

I think that's why it doesn't squeel with the preamp cable. Put a buffered pedal in between your other guitars and the boogey and see if that helps. You could sacrifice true bypass and put a buffer close to the input jack before the signal hits the switch, perhaps?

[ayayay!]

I was just gonna say that sounded like me!  Try the shielded cabling and grounded input when bypassed.  It resolved all of my problems. 

P.S., Isn't John Lyons a great help around here.     And zyxwyvu helped on that one A LOT too. 

[km-r]

yes mr. roger, its like its inherent to me. at least i can say my DB is very loyal to me.

thanks for the reply guys but i dont think i can squeeze in a buffer in the "bypass" line... i have used all shielded wire.

I think that's why it doesn't squeel with the preamp cable. Put a buffered pedal in between your other guitars and the boogey and see if that helps. You could sacrifice true bypass and put a buffer close to the input jack before the signal hits the switch, perhaps?

i will try that, ill put a simple buffer in front, keep the DB on and use an AB box... WOW!