Decibel question

First, keep in mind that in many and perhaps most cases SPL meters do not respond fast enough to capture the full amplitude of a musical peak whose duration may be measured in milliseconds.

Second, recordings which have wide dynamic range, such as many well engineered minimally compressed classical symphonic recordings, may reach brief dynamic peaks of 100 to 105 db at the listening position, yet not seem uncomfortably loud because their average volume may only be in the 70s. While recordings which are dynamically compressed and/or don’t have much dynamic range to begin with, such as many and probably most pop and rock recordings, may very well sound excruciatingly loud at 90 db, since their average volume won’t be all that much different than their peak volume.

Third, keep in mind that as Atmasphere has pointed out in a number of threads here our hearing mechanisms tend to interpret even very small amounts of certain higher order harmonic distortion components as loudness cues. So small amounts of those distortion components, whether present in the recording or introduced by the playback equipment, can make a recording seem louder than it actually is.

Regards,
-- Al

You can get a calibrated microphone for "normal" phones from Parts Express. The imm6 I think it is called. 

Second, how high you can turn up the volume is a matter of speaker efficiency, impedance and amplifier "size" or power output at that impedance. A speaker swap could make your ears bleed. :) 

Best,

E

Am I missing something not being able to listen to 100 plus?

Only you can answer that question. But as you've stated at one point your ears were hurting, regardless of whatever you may be missing, your first priority (IMO) becomes protecting your ears from permanent damage. There are plenty of ear plugs available if your desire is to attend concerts and you're finding the SPL to high. 

You may be interested in reading a related and recent thread here on Audiogon.  https://forum.audiogon.com/discussions/does-it-have-to-be-loud

Am I missing something not being able to listen to 100 plus?

Hearing damage, maybe?

FWIW - I use a Radio Shack Sound Level Meter.
Set to C weighting and Slow response for a display of "average" dB levels at a given volume setting, 75 - 85 is typical at the listening position (around 10-12 feet from speakers). Loud but still comfortable for me is pushing the average to a more consistent 80-85 (same meter settings). At these levels, using Fast response for peaks, I see "typical" peak values of 90-95...and definitely still less than 100 dB.   What's very satisfactory for me might not be for you.  Can't speak to that (or whether your amp/speaker match is ideal).

Hope this gives you additional context.

The iPhone case may cover the microphone, lowering the actual SPL so I wouldn't trust that for accuracy.