passive preamp with remote volume before smash

boyanb · 2074

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Offline boyanb

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on: April 07, 2017, 04:29:09 AM
Hi all,

I am considering adding a passive preamp with volume control before the smash, for example khozmo ( http://www.khozmo.com/stereo_selector.html ).
But I don't know what resistance to choose. Do you have any suggestions? I can choose between 5K ... 250K Ohms.
Thank you.
« Last Edit: April 07, 2017, 11:32:43 AM by boyanb »



Offline fullheadofnothing

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Reply #1 on: April 07, 2017, 06:12:27 AM

Joshua Harris

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Offline boyanb

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Reply #2 on: April 07, 2017, 11:30:38 AM
I have the smash preamp. I would like to add a passive preamp with remote volume control between the sources and the smash preamp. My question is what resistance of the attenuator of the passive preamp should I choose? If anyone knows.
Thank you.



Online Paul Joppa

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Reply #3 on: April 07, 2017, 03:14:20 PM
The impedance of a preamp attenuator - or at least the minimum impedance - is set mostly by the source components. The maximum is set by the preamp itself, through the input capacitance (Miller capacitance of the 4P1L in this case). We have usually chosen around 100K for Bottlehead products, as a reasonable compromise that hardly ever causes any problems.

Paul Joppa