Radio Shack Boundary SPL

[Jon P]

I've been trying to find the SPL level of this mic, but can't find anything that specific. Does anyone know what the rating is? Can it handle being on the inside of a kick like 91? Will the Crown PZM handle a similar rating? Thanks

Jon

[Professor]

I don't mean to sound pedantic or anything, but do you know the SPL level you're going to have inside the kick drum? Because if you don't then having the limit for the mic won't matter much.
Seriously I respect your search for the knowledge first especially when so few people use the specs that way, but it may just be easier to stick it in the drum and see if it works.
FWIW, the Crown 'SoundGrabber II' which is pretty similar has a max SPL listed at 120dB for 3% THD, though that figure would of course shift downward as the battery is drained.

-Jeremy

[Jon P]

No offense taken at all. I was just curious. I still plan on trying the mic this week, but was wondering how much if any damage I might do to the mic. I realize its only a $30 dollar so not much a problem if it gets trashed. But I would like to keep it intact if possible. I did just use it on a bass cab and really like it.

Thanks for the reply and the info on the Sound Grabber.

Jon

[A.David.MacKinnon]

If you mod the radio shack PZM for 9volt power and balanced output it can handle higher SPLs than it does stock. The mod is everywhere on the net and the power supply is more or less the same as the Tape-Op DIY omni mic.
I've used my modded PZM in kick drums with good results. It's very good with another mic out front to cathch more of the low boom.

[river]

In theory, there shouldn't be a max SPL rating for a PZM. PZM=pressure zone microphone. The pressure zone is a thin layer of air molecules next to a flat surface which responds to sound sources by virtue of the molecules vibrating in place in correlation with the frequencies generated by the sound source (kind of like water molecules when heated or cooled). There really isn't any "sound pressure" there, like in an open space where air can compress and rarify. I think I remember hearing that the Boundary mic isn't really a PZM though, has to do with which way the capsule points. On a PZM, I believe the capsule faces the plate, on a Boundary, faces the source, so it probably isn't immune to an SPL limit. Still, it ought to do better than a standard condenser mic. I have an old RS PZM from when the capsules were actually made by Crown. Been trying to find the time to do the mod for balanced, phantom power use.