Re: What defines a subwoofer's SQ and SPL?
You want the speaker to play a note without adding anything that isn't in the recording. To judge this you have to listen to real instruments and then listen to a recording of real instruments, not synthesized bass. With subwoofers I've noticed that you'll hear differences in the definition of strings on a bass guitar, or the double kick pedal drums that can give your speakers a hard time. To my understanding, a lot of this comes from the motor. You want a motor with good control over the cone, so when the note stops the cone stops. Also, a design that aims to reduce distortion should sound better when pushed hard.
Two very technologically advanced subwoofer designs are the JL W7 and the JBL GTI series. They both make for very interesting products to study if you want to find some buzz words to learn.
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