There are many outdoor sheds in the US that have speed limits, and if you go over them for more then a set period of time they fine you up to $2,000 per instance. They run an EKG type sound level meter (calibrated B&K) to eliminate the arguments that gives a minute to minute readout, with a printout at the end of the concert they then add it up
I have never been fined but I know many a sound engineer that has. (The bands management company pays) Unless they have told the engineer to be a good boy, and play nice.
Some bands can afford it
some can not
But inside concerts can go to 112 or higher. Because of the space issue of a small club big PA system, SPL can get up there. Most of the mic companies that quote SPL distortion levels are misleading because they are depending on an external preamp, that may or may not be part of your signal chain. Like the mini XLR to XLR preamps. So the real spl levels of a given mic not mentioning any names, may or may not be very accurate. If used with out the said cable preamp.
I did some consulting work for a Very popular microphone company in the USA, that said the lav mic that made could handle 138db, I had a singer that was distorting it with his voice. We measured it at 120dbA at 3 inches. The mic was 8 inches away from our measurement mic and the lav was still distorting.
So I place very little in what some companies say the distortion amounts are for a given mic. It depends on the termination of the mic too.
Chris Church
Now it gets tricky - AT853 (and probably the smaller AT943) mics overload at very high volumes - your typical club rock gig. This is why people phantom power these mics, or use a 3-wire battery box. Chris Church could build you one of these.
Ok, now I'm getting a little confused. Currently I own a SP-SPSB-6 battery box. Is this a 3-wire battery box? And if not could you direct me in the way of a really good, small phantom power unit or a 3-wire battery box? Thanks.
No. I would highly recommend getting the 3 wire box (or getting your converted if its possible) or going with phantom power+preamp with mini xlr inputs. The mics will sound much better and will easily be able to record loud/bass heavy concerts. It'll save you a lot of heartache in case you record loud rock/metal shows.
I have the same SP-SPSB-6 battery box and have had no problems with brickwalling or too much bass using the cardioid caps. While the SP-SPSB-6 is not the 3 wire box or true phantom powering, it does improve the mics' performance and enhances the SPL levels they can handle to ~125 db. Unless you are taping on stage, or duct taping the mics to a stack, I doubt you will ever expose them to even close to that kind of volume. An occasional transient peak might overload the AT mics in a very, very loud small club if you are not using the battery box since they then can only handle ~110 db. I have pulled a stack tape, however, from the 2nd row in the 100s section behind one of the mains at Shoreline for Rush, a very loud band. I had no distortion/overloading using the line-in (although it felt like the ear wax had melted out of my head and my ears rang for three days afterwards).
The Who was sued back in the 80s for pumping ~110db out of a sound system and causing hearing damage to fans. Since then, it is a quite rare thing for SPL at shows, even loud outdoor shows, to go much over 100 db or maybe 105 db max. A couple engineers have told me at different times, in both No. and So. Cal., that they have been required at outdoor shows under permit from local goverments to run a SPL meter and make sure that volume does not exceed 105db at their legal peril.
The big difference the phantom powering module makes for the mics.: more juice = cleaner signal and wider dynamic range.