suggestions for boosting bass frquencies only..

[b_rogers]

ok heres the problem im trying to address. i will try to explain this as well as i can to avoid confusion,

i have a circuit that is basically a  npn boost into a easydrive then the simply wonderful tone control.

i have tweaked it to sound really good with one exeption. in order to keep the overdrive sounding right i had to use a fairly small cap (.022) to couple the boost into easydrive. any larger value makes it too wooly. it doesnt need less highs, just better bass response.

what would be the easiest way to boost the bass frequencies POST distortion??

combine clean into the signal post od ala sparkle drive? active tone control?

the marshall jackhammer i use has a really good thump to it that i think would sound great combined with the sound of this circuit, and i am pretty sure that has a active tone section but probably more complicated than i need.

any suggestions would be greatly sppreciated

Brent

[seanm]

Once you have cut the bass, it is pretty hard to get it back.

How about a blend control with a low pass filter on the other side of the blend?

[petemoore]

what would be the easiest way to boost the bass frequencies POST distortion??
 >'the way' bass is boosted is by using a LP filter and boosting what's left. If the low pass filter is set low enough all that's left is bass, a gain stage would do the boosting of these lower frequencies.
combine clean into the signal post od ala sparkle drive? active tone control?
 This could be used to pass bass around the NPN boost, and left in the TC, to match the NPN boosts output [no Sparkel Drive circuit knowledge here, offhand] would probably need a gain stage of it's own.

[Sir H C]

If you have an gain stage (follower or common emitter) you can put an RC in parallel with the load resistance.  What this will do is reduce the gain at the higher frequencies and flatten out (so you don't just roll off all the highs).  That in effect can give the bass boost.