Blues Breaker - Increasing gain?

Started by GibsonGM, May 21, 2007, 07:05:45 PM

Previous topic - Next topic

GibsonGM

Anyone have any luck getting a little more drive out of the Blues Breaker?  I love this circuit, but feel it could use just a shade more distortion (without crossing into Dist+ territory!).  I've picked diodes (1 LED and 1 914), and like the crunch - didn't like Ge's in there...could the Fulldrive gain pot mod work on this, to increase the opamp gain and hit the diodes harder?
:icon_twisted:
  • SUPPORTER
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

oldrocker

#1
You might give a 4001 diode a try.  I had some pretty good OD out of them.  Maybe mixed with LED's.  I doubt that it'll give any gain difference though.

GibsonGM

#2
Yeah, I hear ya, Old...I like the OD it gives (a lot), but hoping for something with a little more screech....I'm putting it in a box along with a MOSFET boost, and have room for 1 other FX or stomp switch.  Was thinking of cranking up the gain for leads...we'll see what the mosfet does for that ;o)

EDIT:
MOSFET BOOST AFTER THE BLUES BREAKER   :icon_twisted:  :icon_mrgreen: :o
  • SUPPORTER
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

cbriere

have you tied changing the GAIN pot for higher value, or put a serie resistor witht his pot?
cb

GibsonGM

I did try that, cbriere, and it improved things some. Maybe switching to a 4558 would increase gain, too, from a low fidelity standpoint.  It's the usual thing - I want a pedal to do it all  ;)  SRV, Tom Petty rhythms, and then I want to play leads like Blue Oyster Cult, lol.  Might not be able to pull it off!   

Adding a MOSFET boost to the output really tightened things up, it's driving my tubes enough to make them wail.  If I can tame it a little bit (probably a bigger gain pot), I think I'll have close to what I was looking for. Next build, BSIAB2   ;D
  • SUPPORTER
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

WGTP

#5
Double the resistor in the second op amp that is in parallel with the diodes.  Is it a 220K?  Go to 470K.   :icon_cool:

Between the first and second op amp (2 - 4.7K) 1/2 or 1/4 them.   :icon_twisted:
Stomping Out Sparks & Flames