Adding low pass to rangemaster

[gutsofgold]

I'd like to give a tweaked rangemaster a try. Input cap selector, gain control, and low pass control. Have some questions for the low pass control.

Can I just take something like this at the very end of the circuit?


The Rangemaster has a .01 output cap at the end of the circuit, after the gain control. Would I want the low-pass filter before or after this? Or am I essentially replacing this cap with the low-pass filter?

[station]

From what I can tell, for a full range response, you want to raise the value of the the input cap to preserve the bass frequencies. I believe it's originally a .005 uF, which not going to let much bass through.

I've had good results with anything from 0.047 all the way up to 0.1

[Ripthorn]

The purpose of the rangemaster is to be  TREBLE booster, so adding a low pass is like taking the chocolate chips out of chocolate chip cookies.  If you are looking for something with more to offer, check out ROG's Omega.  It was designed to do the rangemaster thing as well as a full range booster, etc.

To answer you question, however, you could do something like that, though that looks more like a "presence" control.

[aziltz]

keeley puts a tone control on his rangemaster.


unlike the others here, i think the rangemaster would benefit from some subtle treble roll off.  So experiment with what you have there, immediately after the cap coming off of the transistor.

[John Lyons]

The purpose of the rangemaster is to be  TREBLE booster, so adding a low pass is like taking the chocolate chips out of chocolate chip cookies.  If you are looking for something with more to offer, check out ROG's Omega.  It was designed to do the rangemaster thing as well as a full range booster, etc.

+1
Really depends on the amp though. The rangemaster shines as a  treble boost for more distortion at the input of an amp at the edge of breaking up.
On a truly clean amp it sounds BAD! I guess I could see taking away some very high end and still working ok as a treble booster
though.

[petemoore]

  Try various dinky caps across the B/C of the transistor 'till the right amount of HF is lost?
  Treble control at the end is cool / extra knob.
  Some Ge's have more trouble amplifying HF's than others, other amp'll make an RM sound different too. Adjusting EQ at the amp is hard to do while stomping, the right frequency response helps make it unnecessary.

[gutsofgold]

well to be honest, I have an enclosure drilled for three pots. I am trying to make sure of this enclosure and a spare NPN germanium from small bear I have specifically for the rangemaster.

I was hoping I could do an input cap selector, the regular gain/boost pot, and then something else. a tone control would be nice. could I use any average pot+cap passive tone control?

[Ripthorn]

If you really wanted to, you could do a dual concentric pot for a passive baxandall or something like that.  Then again, I tend towards options that are a little more complicated than needed most times.