Is it accurate at all to just buy a calibrated sound monitor and measure my speakers db in my home? Ive seen a few of them on Amazon in the $30 to $80 range. I have a set of JBL L50's which had a replacement woofer put in by a previous owner, and Id just like to know if its higher or lower than the original woofer specs from the factory in 1979. Thanks.

none of these seem appropriate for a large noisy workplace, they are all small handheld with a tiny display. i have a free app that does ALL of these functions and more, using an iphone built-in microphone and is also accurate within 2 dB. if i wanted greater accuracy I could use an external mic. what it can't do and none of these decibel meter can either, is have a display visible from 50ft away high contrast tall numbers and give a visual cue of dangerous levels using a bright LED flasher or something? wall mounted?