Will this switching arrangement load down the FX loop output

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ChrisM
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Will this switching arrangement load down the FX loop output

Post by ChrisM »

[IMG:1023:723]http://img.photobucket.com/albums/v610/ ... hoto-2.jpg[/img]

Even when the switch is flipped to the top position so the pot has no input will it load down the output of an FXs? FXs output have pretty small impedance generally so I think I would be ok.

When the pot is "out" of the circuit it still acts like a varaible path of resistance to ground. I could add a SPST to break the connection from the wiper to the 100nF cap but I'm not sure if I need to?

Thanks...
diagrammatiks
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Re: Will this switching arrangement load down the FX loop output

Post by diagrammatiks »

explain this again slowly chris.

:shock:
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selloutrr
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Re: Will this switching arrangement load down the FX loop output

Post by selloutrr »

diagrammatiks wrote:explain this again slowly chris.

:shock:
Ok good I'm not the only one who is confussed by what your asking.

are you running a passive or active effects loop? or just breaking the signal chain and inserting an FX pedal?

is the 250k pot supposed to be a recovery / volume knob or a mix control? the cap a bright switch?
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ChrisM
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Re: Will this switching arrangement load down the FX loop output

Post by ChrisM »

I left out a lot on that block diagram. Before the FX loop in is a switch for passive or buffering. The switch after (the one you see) is to select between no return control or a return control.

I got it all sorted out now...
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jjman
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Re: Will this switching arrangement load down the FX loop output

Post by jjman »

Yes the output of the "fx loop" is loaded down by 250k. Whether that's too much loading depends upon the impedance of the output of the fx loop. Do you know that figure?

I think you are probably fine unless the loop's output is completely passive. Even then you may be fine especially if all the effects are buffered types.
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diagrammatiks
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Re: Will this switching arrangement load down the FX loop output

Post by diagrammatiks »

ChrisM wrote:I left out a lot on that block diagram. Before the FX loop in is a switch for passive or buffering. The switch after (the one you see) is to select between no return control or a return control.

I got it all sorted out now...
oh good nobody had to decipher your cryptic drawing.

i kept wondering, did he goof and draw a square around something called an effects loop when he meant send/return jacks?

cuz like if there was a return driver before the pot why would you care if it loaded down the output impedance?

and then I was like wait what if the pot if before the return driver?

and then I was like but chris knows everything there's no way he'd put a pot on the return side of return driver in series with return jack??

because that would do fuck-all.

glad you got it all worked out buddy.
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