Should I use a Sound Grabber or GLM-100 to mike a piano?

I am looking for an affordable way to record my daughter's piano playing. I have a limited budget and can't afford a PZM-6D. Can I use a Sound Grabber II to do a grand piano recording? I am using a Tascam digital mixer connected to a PC. The mixer comes with two XLRs and two 1/4" plugs. And what does it mean by "high-Z unbalanced output"?
Joe Wong

Reply: The Sound Grabber is intended mainly for recording conferences and videos. It normally plugs into a miniature cassette recorder or camcorder.  

"High-Z" means "high impedance", or a high resistance to AC current (about 1500 ohms in the Sound Grabber). However, most recorders are designed to work with low impedance microphones (about 250 ohms). An "unbalanced" output is a signal on a cable with a shield and one conductor. An unbalanced output picks up more hum than a balanced output, which has a shield and two conductors.  

If your recorder has a 3-pin professional XLR mic connector, it is designed to work with a low-impedance balanced microphone. All Crown mics except the Sound Grabber and GLM-100E are low-impedance balanced.  

Costing $99 or less, a Crown GLM-100E mini microphone can produce studio-quality recordings. However, it needs a connector and a 9-volt battery.  

A wiring diagram is below. To reduce cost, the GLM-100E has no connector, but you can solder on your own connector.  

1. Solder the red lead to the + wire of a 9-volt battery clip.
2. Solder the shield to the wire of the 9-volt battery clip.
3. Also solder the shield to pins 3 and 1 of the XLR male 3-pin connector.
4. Solder the white lead to the + wire of a 10 microfarad electrolytic capacitor.
5. Solder the wire of the 10 microfarad electrolytic capacitor to pin 2 of the XLR connector.


If you don't want to do the wiring, you could buy a GLM-100 microphone, which already has an XLR connector. It is phantom powered and costs about $200.  

If you are using the GLM-100E, plug the XLR connector (that you soldered) into your mixer's XLR connector. Be sure phantom power is turned OFF in your mixer.  

If you are using the GLM-100, plug its XLR connector into your mixer's XLR connector. Turn ON phantom power in your mixer.  

As a starting point, tape the microphone to the underside of the raised piano lid, in the middle.