On the subject of earplugs and cars, I find the 'classic' yellow plugs are perfect for me. In the car/van I put them in and can crank up the music so that the noise floor of the motorway is almost silence and I don't adjust the eq on the stereo because I don't need to.
I think I must be somewhat unusual because I've only ever been to 2 gigs (or any other loud event) without earplugs (way way back).
Basically, I have never calibrated my hearing to loudness and am probably the only FOH engineer who has never heard his work without earplugs....which is ironic really since I'm so damn good!
I guage loudness and eq by pure experience and unlike every engineer I hear, I sound as good at the end of the night as I do at the start, so the last band on don't sound suffer from tired (fucked) ears.
This calibration comes from balancing everything against the natural sound of a drumkit and other loud accoustic instruments (which I've only ever heard via earplugs or a studio microphone).
I'm sure all the seasonned (deaf?) FOH guys will dismiss this as ridiculous and implausible, but I have to say that I wish more FOH guys and the audience would wear these plugs.....obviously it's too late if your ears have already lost too much gain to compensate.
I get all kinds of compliments for my (never over-loud or over-bright) FOH sound and the next/same day my ears are still ready for my studio work.
* I do always make a point of telling the barstaff/promoters/etc to consult me if they feel the volume is too loud or too quiet....and I always ask at the end to make sure. No complaints yet.
Andy
PS. on a recent trip to the cavern (liverpool) I happened to be talking to the in-house FOH man, who noticed my earplugs and told me that it was a good idea since he had measured stage levels from 115-120dB on a regular basis!
That place was painfully loud on stage even with earplugs! No joke.