A guy asked me to mod his Juice box , here's the schematic (from DOD factory) :
(http://www.zimagez.com/miniature/ea338526a8f21740279727c10a8dfe785c8e7e6ba3d716b82d5101c4337690215e4840166ee0abc19936a1cd45850e15php.jpg) (http://www.zimagez.com/zimage/ea338526a8f21740279727c10a8dfe785c8e7e6ba3d716b82d5101c4337690215e4840166ee0abc19936a1cd45850e15php.php)
He wanted changing the clipping diodes for a led red +1N34A . I did it but the sound is not like I thought . That sound typically like a green ringer, a kind of strange note decay.
Beside, I would like to add gain , bass response, and output level . I put a 1M pot. instead the 140K in the feedbackloop's first AOP to increase the gain, works good . then I cut one C12's leg to put out the gyrator (which cuts to about "800Hz" like a TS does actually) but nothing change, the pedal still bassless. for the low output level I thought increasing the 47K in the feedbackloop of the second aop , but I think doing that will have effect on the "low" control, right ?
The fact is that pedal isn't mine and I don't want destroying that circuit in cuting/bypassing/trying component, the pcb quality is really low and I think it won't love that, by the way.
So, have you got ideas to increase bass response and output level ? Someone has already mod that pedal ?
Thanks.
Looks like the TS mods would apply to the diodes on the opamp feedback loop.
He wanted changing the clipping diodes for a led red +1N34A . I did it but the sound is not like I thought . That sound typically like a green ringer, a kind of strange note decay.
Beside, I would like to add gain, R3.
bass response C5
, and output level.
There's a 20k feedback resistor [looks like it's designated 'RS', I cant' read it}
I put a 1M pot. instead the 140K in the feedbackloop's first AOP to increase the gain, works good . then I cut one C12's leg to put out the gyrator (which cuts to about "800Hz" like a TS does actually) but nothing change, the pedal still bassless. for the low output level I thought increasing the 47K in the feedbackloop of the second aop , but I think doing that will have effect on the "low" control, right ?
He might like D1 and D3 as is, but going up in threshold [such as add another diode for assymetric] will boost output.
Sounds kinda like you know what you're doing, there's info on Gyrators, I just remember if it was Mark, RG and who else helping Ricky Vance figure out tone controls/gyrators.
Thanks petermoore,
So, actually , that box was designed to add drive to an amp already saturated. that explains, I think, the low gain level and output level. Actually the diodes may be removed without losing the tone of that pedal.
DOD made , at least one time, a good and really useable pedal ? :icon_lol: