input selector, to use resistors at the inputs or not

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Is it good practice to use large value resistors at the inputs when designing a input selector?

When looking around on the web I see different approaches to it. Some use resistors between the inputs and gnd while other don't. For instance, Nelson Pass uses some 1M resisors on the B1 inputs to prevent the various potential thumps from switching inputs and turn-on transients. Look for R100, R101, R200 and R201 in the B1 manual

On the other hand the mezmerize DCB1 does not use these resistors. Lots of people are using this board, so the resistors are not really needed right? If someone has some different opinions to this I'd like him to share this opinions, in order to make the best decisions when designing a input selector.

Here's the schematics for the Mezmerize:
P-MEZB1-1V10-schematic.png
 
Right, but if a source has output coupling capacitors it should also have some resistors to drain away the leakage voltage. Otherwise it seems like a bad design to me.

ps. I just realize that I started this thread in the wrong section. Should be in the "analog line level" section. Sorry for that. Perhaps the thread can be moved to it?
 
Would a 1M resistor across the input not inject quite substantial noise into the system? Still at -92dBu self-noise but enough to be the major noise source in many modern designs, especially if followed by gain stages.

Resistor Noise / Widerstandsrauschen

I wouldn't recommend, I'd rather use 100k or less if acceptable. The reduction in switching pops could be nice, though ultimately I'd prefer upstream muting to operate during the input switching rather than this.
 
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Would a 1M resistor across the input not inject quite substantial noise into the system? Still at -92dBu self-noise but enough to be the major noise source in many modern designs, especially if followed by gain stages.

Resistor Noise / Widerstandsrauschen

I wouldn't recommend, I'd rather use 100k or less if acceptable. The reduction in switching pops could be nice, though ultimately I'd prefer upstream muting to operate during the input switching rather than this.

The resistor noise isn't an issue because any active input has that resistor "shorted" by the source impedance of the equipment feeding it.
 
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