What Resistor for Ross Hammer mod

[jimmy54]

Hi folks,

I've got the parts for a Ross compressor and wish to do the Mark Hammer mod (using a 10K, 39K resistor, switch etc.).  I'm using the layout from geofex.  On their layout diagram, is the 150K (to be modded) resistor numbered R18?

[Mark Hammer]

Yes.

Smaller values of the resistor charge the cap up more quickly, re-establishing maximum gain.  Larger values make the cap take longer to recharge.  You probably shouldn<t go smaller than 10k, but could possibly go higher than 150k just as an experiment.  A 250k pot with a 330k fixed resistor in parallel will give you 142k of max resistance.  Stick that in series with 10k and that will get you 10-150k.  As I've noted before, I personally don't get much advantage out of having it variable, but that's just me.  The 3 preset recovery rates do what I need it to do.  The resistance values I've suggested in past are intended to provide a consistent proportional change between fast-to-medium and medium-to-slow.

[jimmy54]

Thanks for the extra info Mark.  I'm in a similar mind to you, I don't need a pot (it would just further increase my twiddling with the settings, and hence reduce my amount of playing time ).  I just like the idea of having a different switchable 'character' to the tone.

Cheers.

[Mark Hammer]

You didn't hear it from me, but sometimes less is more.