Question about r9 on the Kingslayer

[MarkL]

I'm just comparing the Kingslayer to the schematic for the circuit upon which it is based.  I am curious about the Kingslayer's r9 -- the 10K between lug 2 of the "Dirt" control and GND.  What is the function of this resistor?  How does removing it affect the circuit?  Is it there before instead of the control being references to Vb as in the original circuit, it is now references to GND?

[oldhousescott]

It's a slight reconfiguration of the original circuit. Brian will have to answer why he did it that way. The only real difference I can see is that the OD will not be fully grounded out with the gain all the way down. Whether you will be able to tell is another matter.

If you want it to act more like the original, replace R9 with a jumper, and put that 10k in series between lug 3 of the dirt pot and the PCB.

[MarkL]

Thanks for the comment and clarification.

I just finished my build.  I really like it -- fantastic tone.  But I notice that I get unity volume just past 12 o'clock on the volume knob (10KB) when the gain knob is set quite low.  Is that typical?  I subbed in a 25KB pot which helped a little bit, but I'm still seeing unity gain at about 12:00. 

[oldhousescott]

You could always sub a log/audio pot in place of the B25K. That will spread out the volume from off to unity across more of the rotation, but above unity will be scrunched up toward the CW end of rotation.

Unity at noon is not necessarily a bad situation. Having unity at noon gives you plenty of rotation for boost and cut. Many pedals with linear volume pots will have unity at 9 - 10 o'clock and can be rather finicky when setting the output volume.

[MarkL]

That's a good point and something I had thought about after I posted my comment/question.  I don't really MIND having unity at 12:00, I just was not sure if I'd done something wrong given another post in a different thread where the poster said that he/she was getting unity at the 9:00-10:00 positions.  I generally prefer having unity at around 11:00, so I have a hefty amount of space to boost the signal but also enough to cut it as you have suggested.