Crazy Horse wrote:
I see both these listed by sellers, but only the 631 listed on the
Astatic website:
http://www.astaticinstalled.com/products.asp?cat=10

I'm not sure what to make of this. I wonder how the two compare, and
which might be the better value for the money.

One seller:
http://www.sjtelecommunications.com/ast-636l.html
carries both and, I think for the same price.

Any thoughts? Thanks.

A 636L is a communications mike and a 631L is for paging?
That would mean different response curves. Figure a 636L
is good for 300-2500 Hz and a 631L to have more response.

Your radio only responds to the communications curve.
Lots of lows will distort early and lots of highs will splatter.