Mojo Hand Iron Bell Volume

[Meomy]

Hey All,

A couple of months ago I built a Mojo Hand Iron Bell from this layout:




It sounds great and everything seem to work well except that the volume/output on this thing is incredible.
The best tones don't come out until the volume knob is half way up, but by the time that happens its like at least double the volume of the bypass sound.
The volume leap is so huge that there is no way i could gig with this pedal.

Someone else mentioned the volume leap in the comments section, but there was no answer/comment on how to fix it.

Can i change some pot values or do anything to correct this?
One idea i thought of would be to make an LPB boost with a trimmer and put it after the circuit and then just lower the output volume with the trimmer. Would that even work or would it jack up the tone? Anybody have a better idea?

I REALLY want to keep this pedal, but if i can't tame the volume its useless and will end up getting cannibalized for some other project.

Thanks again for your time and help.
 

[IvIark]

Try increasing the value of the 2K resistor at Q4 emitter.  That will reduce the gain of the final recovery stage which is there to make up any losses from the tone stack.  The gain is the collector resistor value divided by the emitter resistor value, so at the moment is around 5x.  Increase that resistor and the gain will drop by the same calculation.  See if that can tame it enough for you.

I would say though that virtually every muff I've ever used has been very loud.

[rocket88]

I totally agree with Mark. The big muff has a lot of output, I mean a metric ton worth of output. Another idea  you can do, which I'm planning on making for one of my I built basses just overpowers and sends pretty much every pedal into distortion when I turn the preamp on, is make a simple volume attenuator that what you turn it on it cuts the output, but keeps everything else the same. Sorta like a second volume control in its own enclosure.



No need for power, but you could just put this into the muff enclosure after the output. And give it power so it can have an LED to tell you when it's on.

[Vince]

Another thing to try is using a A100k instead of a B100k for volume as in my RAMS heads, if I use a B100k I get unity at 9am but using a A100k I get unity at about 1-2pm.