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I need to know if its possible to add a LEVEL knob control the intensity of the effect (dry vs. wet) on a phase 90.... and on the chorus too.

What you want is a mix pot, to vary the wet/dry balance.

Yes, that's possible (on both).



K

what about a pure level knob, not a mix? the phase is pretty subtle effect. a bit of a volume boost would be nice.

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Everything's possible...

The mix section of the Phase 90 consists of two 150k resistors in front of the output buffer. Experiment with 2x100k + a 100k pot for a mix option.

The output buffer is a 2N4125 transistor and a 150k resistor. Experiment with the size of this resistor to see what gives you a suitable higher max output. When you have that you can replace the very last 150k resistor to ground with a pot...

K

This "mix mod" replaces the dry 150k and the wet 150k mix resistors with a 250k pot and two 27k resistors.

The idea is that you want to keep an approx total mix resistance of 300k to maintain unity gain.

If you boost the wet signal by dropping the wet resistance to 50k, you need to cut the dry signal by increasing the dry resistance to 250k so that there is no overall volume boost. And this of course works conversely.

So you could therefore boost the overall signal by either decreasing just one of the mix resistors without increasing the other or decreasing both. However, you are affecting the signal level before the 2N4125 output buffer and you may cause clipping if you boost too much.

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*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Thanks Keith.

According to your drawing, I should remove the 2 150k resistors right ?

yes

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com