I'm using this NPN switch to turn on and off a clean guitar signal (as part of a much bigger circuit not seen.) The base is connected to the switch, which gives the base 9V through a 1 megaohm resistor. The idea is that when the switch is on it will allow the clean signal from the collector to the emitter.

LTspice does not like this part of the circuit at all, as it takes an extremely long time to simulate, if it doesn't crash. I have a feeling it's a terrible little circuit, but I'm not sure why. Is this circuit acceptable, or is there something I'm missing?

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    \$\begingroup\$ You want to use a BJT as an analog switch? This is one of those places where MOSFETs are likely better fits than BJTs. Besides, the collector is only very rarely used as a signal input lead. (I'm trying to recall a case and I'm coming up short.) And we cannot help much with the simulation issues if you insist on hiding your schematic. \$\endgroup\$ – jonk Feb 6 at 3:07
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    \$\begingroup\$ Probably you need a DC path to the collector. But yeah, this sounds like a good application for a MOSFET, or several MOSFET's. What is the amplitude (signal level) of the clean guitar signal? Is it straight from a guitar or is it already pre-amped up so it is line level or something? \$\endgroup\$ – mkeith Feb 6 at 6:10
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    \$\begingroup\$ The simplest and highest fidelity solution would be to use a relay. Zero distortion when on. True bypass when off. \$\endgroup\$ – td127 Feb 6 at 6:36

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