Hurting Mics with Bass

Archived from groups: rec.audio.pro (More info?)

"Luther Bell"
>
>I recently purchased a pair of JBL MP255S subwoofers for the concert
> hall that I work at. I just got done hooking them up and I thought of
> an interesting question. This is a 1,000 seat house and we have a pair
> of DPA 4011 mics hung in front of the stage for recording performances
> (around 10' in front of the stage and 10' above the stage). I am just
> wondering if it is possible to harm a mic with loud noise (in this
> case, bass), even though you are not using the mic at the time. I
> think that it is possible, but I'm just checking.


** Sure its possible - just hold it near the mouth of a 150mm Howitzer
when it is being fired.



> If it is true, I
> invite suggestions that will help me get around this problem. I
> basically want to know if many db's (the sub's limit is 135db @ 1m) of
> bass will harm a mic, and what possible ways there are to get around
> the problem.


** The DPA 4011 is speced to handle 158 dB SPL at any frequency - since it
is a condenser mic. To damage that mic would need much higher levels
gain - ones that might prove fatal to humans.

Dynamic mics are another story and can be damaged by loud low frequencies -
ie like those found INSIDE a sub bin !!!


> It is possible to pull the mics up but it takes a lot of
> work and I'm saving that for a last resort.


** ROTFLMAO.....

Anyone for paranoia ??



.............. Phil

Archived from groups: rec.audio.pro (More info?)

Luther Bell <freakoftheweek0000@hotmail.com> wrote:
>I recently purchased a pair of JBL MP255S subwoofers for the concert
>hall that I work at. I just got done hooking them up and I thought of
>an interesting question. This is a 1,000 seat house and we have a pair
>of DPA 4011 mics hung in front of the stage for recording performances
>(around 10' in front of the stage and 10' above the stage). I am just
>wondering if it is possible to harm a mic with loud noise (in this
>case, bass), even though you are not using the mic at the time. I
>think that it is possible, but I'm just checking. If it is true, I
>invite suggestions that will help me get around this problem. I
>basically want to know if many db's (the sub's limit is 135db @ 1m) of
>bass will harm a mic, and what possible ways there are to get around
>the problem. It is possible to pull the mics up but it takes a lot of
>work and I'm saving that for a last resort.

It is possible to damage mikes with low end. Putting one of the newer
TG replacements of the Beyer M-88 into a kick drum will wreck it, for
instance.

BUT, the DPA 4011... I would be VERY surprised if you could damage that
in any way. High SPL levels won't hurt it. Dropping off the catwalk
fifty feet onto the floor won't hurt it. Sonic booms are no problem.

Now, it's true that it may not accurately reproduce insanely high bass
levels, or the sound of the mike being dropped on the floor... but if
you need to do that, B&K mikes for that too!
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."