peppermill OD @ 18V?

[alderbody]

has anyone tried running the ROG peppermill OD at 18Volts?

Could something like that be done? would there be any tonal benefit? (headroom, clarity, whatever...)

Since all the components (i used for mine) can take 18V, what's the story with the Drain voltage of the J201?
Should it always be at half the supply voltage or at 4.5Volts no matter what?
And what about the Source voltage of the J201?


...just an idea.

Classic "what if" question...   

[petemoore]

  I think the Jfet will bias ok at 9 or 18v with the same resistors values, you could always test it and mod for best bias...
  Could something like that be done? would there be any tonal benefit? (headroom, clarity, whatever...)
  Headroom increases with bigger supply voltage, whether it's a 'benefit'...hard to say and is subjective anyway...I guess in the Peppermill, being an OD, it'd change the sound, probably make it cleaner/more sterile...conjecture on my part...
  Make certain all your caps are rated higher than the applied voltage...
  what's the story with the Drain voltage of the J201?
Should it always be at half the supply voltage or at 4.5Volts no matter what?
  Right around 1/2v or adjusted by ear.

 


 

[JimRayden]

I believe raising the supply voltage for a booster han be quite a healthy bonus as it will help it stay clean but generally, I'm a bit skeptic about raising voltages in distortion devices.

Let's assume you've got a three-stage distortion, two last ones of which are ment to be run into overdrive by the first. Now, if the first stage stays clean at 9V, it will also stay clean with 18V and it boost as much as it does with 9V. Now, since the second stage has twice as much headroom, let's assume it will not distort with 18V. Then you've got a rediculous amount of clean boost smashing into the last stage, which will not sound in any way similiar to the original circuit. Originally, the distortion was produced by both 2nd and 3rd stage to make it smoother. The circuit was tuned to do that, and if you use 18V, you will need to retune the circuit to match that (higher gain transistor for the first stage?), in case you want to make it sound as it was ment to be.

Other than that, higher (or lower) supply voltage can be a quick and easy mod, just to make your circuit sound different - it might even sound better to you.

Now, as to a 2-stage distortion like Peppermill, raising the voltage will make the circuit have less gain (distortion-wise) and alot more output volume. 18V will make it sound cleaner.

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Jimbo

[petemoore]

  I was about to just add a 'poppy' switch [so I could turn down or go to standby, hit the switch and be at a different supply V]...so as to try 9.4v and 17.2v supply mods on a Booster/Dist+ box..nahh
   I think I'm going to pull the MAX Converter and convert back to 9.4v on that one though.

[billings]

I did this on the breadboard and didn't like it.  The output was loud enough that for a large chunk of the volume knob's travel, anything after it in the signal chain would clip in a big way.  I guess I should've realized that's the intention, but unless I'm right in front of a the amp, what's so great about that?  At the most, it saves a booster, but even then you lose the choice of which booster to use.

[JimRayden]

I did this on the breadboard and didn't like it.  The output was loud enough that for a large chunk of the volume knob's travel, anything after it in the signal chain would clip in a big way.  I guess I should've realized that's the intention, but unless I'm right in front of a the amp, what's so great about that?  At the most, it saves a booster, but even then you lose the choice of which booster to use.

tip: use a log taper pot.

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Jimbo

[alderbody]

Thank you all for sharing your thoughts.

since it's safe to do it, i'll give it a try.

just another experience...