affordable ribbon mic for guitar cab micing?

Most cheap ribbons can't handle high SPLs at low frequencies. Make sure you're aware of what the mic is capable of before you put it on the grill. Otherwise, you'll have to put the mic 6-12" (or more) from the cab to prevent blowing the ribbon, and it's a good idea to slightly angle the mic downward slightly so the ribbon isn't subject to the full force of the speaker.

Royers can handle it... :heh:
 
I think all the chinese ribbons are rated at 1k.

For example the APEX 210 can handle 165db @ 1k.

The Royer 121 can handle 135db @ 20Hz.
 
i've heard from many people that the apex 205 is a better mic than the 210, although i've never used either myself...supposedly there are a lot of design/quality issues with 210 that don't seem to happen with the 205 - and the 205 is cheaper. i've heard clips of a 205 w/ lundahl transformer compared to an AEA ribbon, and the difference was almost miniscule

the cascade fathead is also supposed to be a pretty killer mic, and comes in at less than $200...it also has a thinner ribbon than a lot of the other chinese-made mics
 
A friend of mine has a shinybox ribbon and said it's great. I heard a sample with it and some acoustic and it did sound pretty cool.
 
http://cascademicrophones.com/ The Fathead II is an incredible mic for guitars at the price. It's a little more midrange heavy than the 121 and the high end isn't as open but for the price it's a must have

Shinybox mics are also really good. Though with either mic, definitely put in a Lundahl transformer (or if you can't/don't know anyone who can, order it that way stock). It makes a huuuuge difference.