Hey Harrison, in order not to confuse others, “handling” decibels (dB’s) is not the proper term here. Decibel is just the measure for sound pressure level (SPL). Your speakers “handle” Watts (up to a maximum) at which point they will produce a certain amount of dB.
The official measurement for SPL is taking by feeding 1W RMS pink noise into a speaker and measuring the dB’s at 1m distance. This is the indicator of the efficiency of your speaker. The other is max. SPL and is the amount of dB when driving your speaker at the maximum rated power (again RMS). The tricky part here, is that this is maximum rated power at a certain amount of distortion (THD), usually indicated as a %.
While you can calculate the SPL pretty easily (a simple volt meter will help establish a pretty tight 1W setting on the amp with pink noise), calculating the max SPL at home is a good indication at best. To get the exact number more and expensive gear is needed.
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