squished-out bottom end on boosters

[CoolJohnny]

no matter what combination of input/output caps i try, i always seem to get this badly compressed (as in not the good kind), squishy sound on the lower strings when the effect is maxed out and i hit the strings with reasonable force.

the circuit is the utility booster from folkurban. i found it to be very transparant at low and moderate boost settings, though i did change the boost pot 10K around a 22uf cap to ground off the emitter to 5K (all the 10Ks i have are occupied in other effects).

i have also been experimenting with different resistor values from collector to 9V+, from the suggested 10K all the way to 180K; the higher the value, the hotter the  boost at the counterclockwise position of the pot...i think 10K is far too low

in any case, is this unpleasant bass response a limitation of the transistor or is it in the circuit path itself?

[Joe]

Try to change resistors so the point right at the top of the transistor is at 4.5v, and see if that helps. What transistor are you using?

[Steben]

Try the 10k pot, it should give less gain and distortion IMHO. Like you said on lower settings its fine.

[petemoore]

  I just whipped one up [Utility Boost] and used a 10k trimpot [I don't have a regular one handy either, and popped in a 2n3904...sounds pretty clear for the most part.
  Then I tried a J201, just popped right in and sounded good, less gain than the 3904 I think.
  Not sure what's up with the 'squishy'...I didn't notice anything much except just a touch of color and otherwise strong pretty clean boost.