Guitar Mic vs Guitar Mic-B

What's the difference between your two mics for acoustic guitar?
Both mics sound the same, but they have different powering and connections:

Guitar Mic: 
For temporary mounting
Phantom powered
8-foot cable from mic goes to an XLR connector
Connects to a sound-system mixer or to an instrument amp that has phantom power
Also connects to any phantom power supply, which connects to an instrument amp or mixer that lacks phantom power

Guitar Mic B
For temporary mounting
Battery powered. The battery lasts about one year.
8-foot cable from mic goes to a battery box that lies on the floor
1/4" phone jack connector in the battery box
Connects by a guitar cord to an active direct box, instrument amp, or effects pedals

The Guitar Mic and Guitar Mic B can be converted to wireless operation using our wireless mic modification.