Wayne Parham Messages: 18790 Registered: January 2001
Illuminati (33rd Degree)
No, that's not right. They are barely loafing at 20 watts, that's less than 5% power and distortion is less than 1% at this power level from 100-500Hz. It is higher at lower frequencies, but still too low to be noticeable. At 40Hz, it's still in the single digits at 60 watts, so you can't hear it. That's as good as it gets for a midwoofer.
I'm thinking your speakers were probably reconed with cheap parts. This isn't uncommon for used JBL speakers. If they're reconed with genuine OEM parts, they're every bit as good as the originals. But there are some cheap Chinese recone kits that are just terrible. They look the same, but definitely don't sound or measure the same. Sorry about that, but I'd say either send 'em back to the place you got them or send them to a recone shop that you trust to use genuine JBL recone kits.