No Knob Easy-Face?

[jimmy54]

Hi fellas,

I've built the Easy-face using the vero layout below:

http://aronnelson.com/gallery/album17/EASY_FACE_VERO

As I basically have both the pre-gain and volume controls maxed out, how would I go about modding it to a no-knob version?

[jeroen_verbeeck]

Like this:

[pyrop]

Ok jimmy54
For the pregain run a jumper from pregain 3 to pregain 2 & place a 270K resisitor from pregain 2 to pregain 1.
For the volume place a 470K-510K resistor from vol 3 to ground.
Out will be from vol 3

pyrop

[jeroen_verbeeck]

Why those resistors ?
He want's it maxed, so I figure that's the least resistance as possible.

[jimmy54]

That's what I wasn't sure about, whether I should just uses jumpers to give a zero resistance or resistors equal to the max resistance of the individual pots.

[jeroen_verbeeck]

I'd go with the jumpers. I've never had any resistor make my signal louder 

[pyrop]

Why those resistors ?
He want's it maxed, so I figure that's the least resistance as possible.

Yes he wants it maxed. But as it is now with the pregain 3 is always connected to ground through the 250K pot AT 250K.
The pot only regulates how much signal goes the the base of Q1 through the wiper "pot 2"
Same for the volume pot.
So if jimmy wants to keep the output as it is (pots maxed) you need to put the resistors in to simulate as if the pots maxed.
If you dont add the resistors the output maybe way to much! It will probly affect the tone as well.

pyrop

[John Lyons]

Yes, Just measure the pots at the settings you like and sbstitute with fixed resistors.
The input and output need the ground reference in order to sound the same as with the pots maxed. Plus depending on which LED indicator scheme you use you will need the ground rreference.
The millenium bypas and Joe davisson's LED trick need at least 100K resistance to ground in order to work. Plus this will help with pops in the switching.

[petemoore]

  If The volume pot is 100k, 100k resistance from output to ground, this resistance through the pot determining the output impedance.
  A FF has no input resistor referenced to ground...er I suppose the 100k > 1k counts.

[jeroen_verbeeck]

Aah, I think I get it know Pyrop.
I corrected the schem above, is that right ?

[jimmy54]

Thanks for the help fellas, I'll try with the resistors later.