Passive Loop Placement?

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FourT6and2
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Passive Loop Placement?

Post by FourT6and2 »

If you were forced to install a series, passive FX loop in a cascaded gain-stage Marshall circuit with a post-tone stack master volume, would you choose to put it before or after the master volume? i.e. on the preamp side of the MV or the PI side of the MV?
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LOUDthud
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Re: Passive Loop Placement?

Post by LOUDthud »

The high peak to peak Voltage signal coming off the Treble control is too much for some effects if they don't have their own level control at the input.
FourT6and2
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Re: Passive Loop Placement?

Post by FourT6and2 »

LOUDthud wrote: Mon Jun 23, 2025 10:24 am The high peak to peak Voltage signal coming off the Treble control is too much for some effects if they don't have their own level control at the input.
Roger. So after the MV is better.
pdf64
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Re: Passive Loop Placement?

Post by pdf64 »

FourT6and2 wrote: Mon Jun 23, 2025 4:07 pm
LOUDthud wrote: Mon Jun 23, 2025 10:24 am The high peak to peak Voltage signal coming off the Treble control is too much for some effects if they don't have their own level control at the input.
Roger. So after the MV is better.
Yes.
At lower settings of the master volume control's rotation, the 'send' output impedance may be lower.

But whichever, regular pedals in this scenario will reduce how hard the output stage can be driven, so for serious usage, a passive loop is a bodge.
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