Crown CM-700 manual Harp Miking, Lavalier Mic EQ, Miking an Electric Organ

Mic Memo

Harp Miking

Here's an unusal miking applica- tion for sound reinforcement. How do you mike a folk harp? It is a small instrument about 4 feet tall.

Try a Crown GLM-200, a mini mic with a hypercardioid polar pattern.

GLM-200 hypercardioid mic

Mount the mic inside the harp near one of the sound holes. You can attach the mic by taping its cable to the harp, or by using the supplied GLM-UM Universal Mount.

Ask the harpist to play as you monitor the sound. Adjust the angle and position of the GLM- 200 until you hear a tonal bal- ance you like.

Lavalier Mic EQ

Many theater sound systems employ handheld mics for sing- ers and lavalier (clip-on) mics for actors. Sometimes the sound operator is asked to make the lavalier mics sound the same as

the handheld mics. What sort of equalization is needed to do this?

First, note that nearly all hand- held vocal mics are directional, so they have proximity effect (bass boost when used close to the mouth). Omnidirectional lavalier mics have no proximity effect. To simulate that, you might boost 4 to 6 dB around

100Hz. (Be careful with feed- back whenever you apply an EQ boost.)

Lavalier mics have a built-in high end rise to compensate for being off axis to the mouth. You might need to do more high-fre- quency tweaking by ear. Also, most lavs exhibit a peak around 630 Hz (about 3 or 4 dB, less than 1 octave wide) due to body diffraction and chest reso- nance. Cutting that frequency by the same amount can remove the "puffy" sounding midrange peak, making the lav sound more like the handheld mic.

Miking an Electric Organ

Some houses of worship feature an electronic organ. Often it's necessary to feed the sound of this organ into the sound sys- tem. It seems reasonable to find

aline-level signal within the electronics and connect to it, or connect to the organ’s speaker terminals. Unfortunately, these connections can cause several problems:

•Ground loops can create hum.

•You might be held liable for messing with the organ electron- ics.

•The organ technician might remove the connection.

•Many organs don't have a composite or full-range feed, meaning that the electrical sig- nals to the various loudspeaker drivers are bandpassed. If you tap off a loudspeaker you may not get the full spectrum of the organ. If you combine the band- passed outputs to get a full- range feed, you might be held liable for tampering.

•A lightning strike that gets into the organ electronics might get into the audio system, or vice- versa.

Using a mic instead of a direct connection avoids all the prob- lems mentioned above. A close- up omni mic, strategically placed, will pick up very little of the room and other sounds. We suggest the Crown GLM-100 mini omni mic. It's very small and picks up down to 20 Hz.

Note: This close mic placement is for sound reinforcement, not recording. If you want to record the electronic organ, place a pair of mics several feet away (about 12 to 20 feet) to pick up the room reverb as well as the sound of the organ.

The GLM-100 looks the same as the GLM-200 pictured on this page.

Thanks to Pat Brown of Syn Aud Con for this idea.

For more information, call 800-342-6939

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