reposting -- problem with my Kingslayer

[MarkL]

I asked this question a few days ago, but nobody replied, so I'm trying again.

On my Kingslayer, the volume/output seems somewhat weak based on other comments posted out here saying that they've hit unity volume with the knob set at about 9:00 to 10:00.  I am hitting unity volume only at about 1:30 if I have the gain all the way down.  When I turn the gain up a bit, I hit unity volume at 12:00, but that doesn't seem right...and that's even with a 10KC pot instead of the 10KB.  Can anybody suggest what might be the problem here and how I might fix it?  Or is this just the nature of the circuit...i.e., does the gain knob need to be at about 9:00 in order for unity volume to be achieved around the 12:00 mark on the volume knob?

[jkokura]

There are a lot of mitigating factors involved here. What is the actual value of the parts you used? What is the actual response/characteristics of the ICs you used? What is the other pedals and what is the overall signal chain like?

What I often tell students I work with is "adjust knobs with your ears, not your eyes." What I mean is - does it matter if unity volume is at 12 or 1:30 on the dial and not 11 as long as it sounds right to your ears? If it doesn't, then it should be adjusted, but if if it does, I wouldn't say that anything is wrong.

Another good question is 'do you need more boost than is available when you hit max?' If you do, then you might need to make adjustments. If not, then maybe it's fine as is?

[madbean]

I don't see that necessarily as a problem beyond the possibility of a wider variance on the particular pots you are using (they tend to be up to +/- 20%). I guess my question is: does it have enough output for you when using it at max Vol/min Gain (IOW as a clean boost).

It is possible that you have used a wrong value resistor somewhere...one that sets the relative gains. These resistors are R9-R11, R15, R19, R21-23. If all those resistors are the correct value, then I would check to make sure you are getting +/-9v in the right spots. That would be pins 4 and 11 resp. on IC1. The voltages on the other pins should be 0v.

edit- Jacob beat me to it!

[MarkL]

Thanks to both of you for clarifying some things for me.  I think I may have found the "problem".  On my build, I replaced the value of R19 from 392K to 150K, and the value of C14 from 470pF to 2.2nF.  Part of the reason I did this was because I incorporated a boost mod that brings R15 down to 6.8K, and at high gain settings, I was getting squealing and oscillation.  With the replaced R19/C14 values, the oscillation went away.  But I wonder if this affected overall volume output as well.  What do you think?

For the record, I used a TL2072 for IC1 and an OPA2134 for IC2.  Don't know if that really matters but in case it does...well, there it is.

[wstimson]

I'd say that's more than enough substitutions/deviations to account for any relative change in volume. 
As long as the pedal sounds the way you want it to and has enough volume for your needs, I'd not spend any more time worrying about it.

[MarkL]

Thanks.  And please pardon my strange comment on my earlier post regarding  "IC1" and "IC2".  I built up a similar Klon-sequence project alongside the Kingslayer for comparison purposes, and that one used two IC's and my brain somehow conflated the two projects.  Apologies.