Increasing the headroom on an EgoDriver ver.4

[jasonphilly77]

I built my EgoDriver Ver.4 a few years back and I've love it,... mostly. When I have the gain knob all the way down or barely on at all, I'd love to have LESS clipping. Is this possible? To lower the "grit" or "distortion"? It's just has too much at low settings fro my taste. Just curious if there is a mod I can do to give it more headroom. I already run it at 18V most of the time and it's still too much. Any help would be appreciated.

[sonnyboy27]

You could lower the value of the gain pot to a 500k Log pot. That would give you a wider sweep across the lower gain range.

[madbean]

When the Gain pot is all the way down, regardless of its value, the 18k resistor in the feedback loop is setting the minimum gain. In this case that gain out of that first stage is set by (18k+2k2)/2k2 = 9.18. Lower that 18k to 2k2 and your minimum gain will be 2 instead of almost 10.

[jasonphilly77]

Great! Thanks for info. I'll try lowering that resistor value and see where it lands. Peace!

[jasonphilly77]

So just to be clear... I simply replace the 18k resistor at R5 to a 2k2 resistor?

[madbean]

Yup

[jasonphilly77]

Thanks to both of you!

First I lowered the resistor at R5 from 18k to a 2k2. Worked great when the gain was down all the way! Very subtle and cleanish "crunch".

Then I decided that having a wider sweep in the lower gain range sounded like a good idea too. So I swapped the 1MA Gain pot for a 500K Log and it worked perfectly.

All the dynamics are still available and it seems to clean up even MORE than before with my guitar's volume knob.

Thanks for the info and quick responses! Made my Monday.

Cheers!