SHO with 50k output resistor. Unity gain?

[nonost]

Happy new year guys! I've recently changed the output resistor of both SHO inside my Super Duper clone from 100k to 50k. I took this from one very informative post by the user Galapagos in the following thread http://guitar-fx-layouts.42897.x6.nabble.com/Super-Duper-Build-problems-td1775.html

With this update you don't get unity gain with the crackle pot all the way down... Now I'm wonder if I'm going crazy or what but I would swear that I got unity gain with the pot fully counter clock-wise before I changed the resistors. I would really appreciate if anyone could verify this . Beside this, I don't feel any differences, I thought it would be less trebly...but I can't tell.

[nocentelli]

This is normal: In short, lowering the output resistor will allow more signal to ground, reducing the max + min output levels.

The output resistor and output cap together form a high-pass filter (as does any output cap and volume pot). Higher resistor values or cap values bring down the roll-off frequency for this high pass, allowing more low frequencies through. Conversely, reducing the resistor by half will raise the roll-off frequency, theoretically meaning less bass, which might actually be perceived as brighter/thinner/treblier but may well not be noticeable as anything other than a slight reduction in output volume when crackle pot is at minimum. Not sure why the newer version has this reduced output resistor: I'd be tempted to temporarily replace the 47k/100k resistor with a 100k pot, find the approximate resistance for unity gain at zero on the crackle pot (presumably btween 47-100k), measure pot resistance and replace with a fixed resistor of near that value.

[nonost]

 Hi nocentelli. Thank you for the explanation. I'm a beginner at this and not very technical at all, so I really appreciate it.

 I've put back the 100k resistor and I still got unity at the same level. I thought I got unity with the crakle knob at minimun and 100k resistor but I was definitely wrong. It seems bassier to me with the 100k, which makes sense with your comment above.

[nocentelli]