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Looping problem, need help

Posted: Thu Nov 04, 2010 8:39 pm
by Berto
Yesterday I built a box with a two circuits in it to isolate the chorus from the distortion. here is the line up:
Zoom PD-01>Turbo Rat
tuner>BBE orange squash>loop box{ }Boss CEB-3
Boss OC-2

There is a large volume drop on the distortion line of the circuit when the pedals are on and the volume knob only start working at about 4 o'clock on both the rat and zoom.
There is a switch before the line out to the octave (OC-2) so i can keep out the dry signal when I only need distortion. When I turn the switch off there is an incredible volume drop.
Is there anyway to fix this problem?

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The lose jack isn't effecting the signal.

Posted: Thu Nov 04, 2010 8:47 pm
by wwrrss
LOL WUT?


can you draw out the circuit?

Posted: Thu Nov 04, 2010 8:52 pm
by Berto
its just one input that goes out to two jacks, one of which has a two position toggle. The next circuit is two inputs going into one output, pretty basic.

Posted: Tue Nov 09, 2010 1:02 am
by Berto
is there anyone that can help me out?

Posted: Tue Nov 09, 2010 1:14 am
by Zack
It could have something to do with your switch. From what I can see from the picture it looks like it's a 2 prong? Meaning that I don't really see how the connections are wiring up correctly, ie grounding and such. You should look over your solder connections (I don't even know how you managed to get those jacks going with the pcb cracked off). What exactly is the switch used for, just going from "output 1" to "output 2" on the red segment of the circuit?

Isolation could be another problem or maybe pedal placement in your chain.

I'd suggest taking it apart and cleaning up your connections/parts because they may or may not be shot/burnt out because right now it looks like a little like yun's pedals.

Posted: Tue Nov 09, 2010 1:27 pm
by NickS
Berto wrote:Yesterday I built a box with a two circuits in it to isolate the chorus from the distortion. here is the line up:
Zoom PD-01>Turbo Rat
tuner>BBE orange squash>loop box{ }Boss CEB-3
Boss OC-2

There is a large volume drop on the distortion line of the circuit when the pedals are on and the volume knob only start working at about 4 o'clock on both the rat and zoom.
There is a switch before the line out to the octave (OC-2) so i can keep out the dry signal when I only need distortion. When I turn the switch off there is an incredible volume drop.
Is there anyway to fix this problem?
Yes. Use a proper mixer stage instead of connecting the outputs of two pedals together.

I think your diagram is more like:

Code: Select all

                                   --Zoom PD-01->Turbo Rat--
tuner->BBE orange squash->loop box{                         }--->Boss CEB-3
                                   ----o-o-Boss OC-2--------
 
Outputs of effects pedals are often low impedance, especially buffered pedals. They expect to drive a high impedance like the input of another pedal. Trying to drive the output of another pedal is likely to result in noticeable volume drop.
If the volume pot is on the output, the way the pot works can be affected too.

Posted: Tue Nov 09, 2010 1:40 pm
by Mike
Build a proper active mixer like NickS says or use a proper true bypass DPDT switching mechanism.

Posted: Tue Nov 09, 2010 7:30 pm
by cobascis
I'm digging that box... is it from an old power amp or something?

Posted: Tue Nov 09, 2010 8:45 pm
by Berto
NickS wrote:
Berto wrote:Yesterday I built a box with a two circuits in it to isolate the chorus from the distortion. here is the line up:
Zoom PD-01>Turbo Rat
tuner>BBE orange squash>loop box{ }Boss CEB-3
Boss OC-2

There is a large volume drop on the distortion line of the circuit when the pedals are on and the volume knob only start working at about 4 o'clock on both the rat and zoom.
There is a switch before the line out to the octave (OC-2) so i can keep out the dry signal when I only need distortion. When I turn the switch off there is an incredible volume drop.
Is there anyway to fix this problem?
Yes. Use a proper mixer stage instead of connecting the outputs of two pedals together.

I think your diagram is more like:

Code: Select all

                                   --Zoom PD-01->Turbo Rat--
tuner->BBE orange squash->loop box{                         }--->Boss CEB-3
                                   ----o-o-Boss OC-2--------
 
Outputs of effects pedals are often low impedance, especially buffered pedals. They expect to drive a high impedance like the input of another pedal. Trying to drive the output of another pedal is likely to result in noticeable volume drop.
If the volume pot is on the output, the way the pot works can be affected too.
Yeah thats what i meant to show, i guess the script didnt come out as i wanted. Can you explain what you mean by a mixing stage?

Posted: Tue Nov 09, 2010 11:58 pm
by NickS
Do you want a mix of the two chains, or do you want to switch between the two?

If you want a mix, best use an active mixer circuit like the one at
http://www.casperelectronics.com/images ... xer_sc.gif with just two inputs. Actually, you could do a simpler circuit but I don't have time to draw it just at the moment.

A cheap improvement might be to put a 4K7 resistor between each of the outputs and the input to the Boss CEB-3. You'll probably still notice a volume drop but it should be less severe.

Posted: Wed Nov 10, 2010 1:44 am
by cobascis
I think he wants to have a dirty original signal, but still send his clean signal into the OC-2 to get a clean octave? I may be way off base.

Posted: Wed Nov 10, 2010 4:16 pm
by Berto
What cobacis said. I want the lower octave to stay clean, otherwise it gets muddy when the lower octave is distorted