SM57 - connect to low or high impedance input?

SteveFreides · #1 03-14-2012, 07:48 AM

I have: Shure SM57 mic, AI Ten2 combo amp.

Will the impedance match be better using the XLR connection, which is low impedance (around 600 ohms, I think) or a 1/4" which is around 1 Mohm?

I vaguely recall reading that the AI XLR impedance was designed for condenser nicer mics than an SM57 but that's what I've got here.

NB: This isn't for my bass at the moment, it's for a singer, but the question is a generic one . I'm going out to buy mic cables, which is why I ask. I'm planning to buy XLR on both ends with an adapter to use the 1/4" input of the AI if it turns out to work better.

Many thanks in advance.

-S-

RDUB · #2 03-14-2012, 08:22 AM

SM57's are low impedance - use the XLR.

RustyAxe · #3 03-14-2012, 08:38 AM

Modern mics are low impedance, regardless of type. 1 mOhm input is most ideal for piezo type pickups.

SteveFreides · #4 03-14-2012, 08:50 AM

Thank you very much.

-S-

fep · #5 03-14-2012, 08:59 AM

The xlr connection will also have less noise than using a 1/4" adapter.

xlr, is balanced audio which splits the signal, reverses the phase for the cable run, then puts the signal back in phase and combines it at the input, it cancels any noise picked up during the cable run.

Don't quote me as I may get the details not quite right. Check this:

Balanced audio - Wikipedia, the free encyclopedia