Group Delay Paradox:
Having now read the treatise on adding a sub-woofer by the Soundoctor (courtesy of JL Audio's Help Center), I'm puzzled by this essential statement: "The typical group delay through a modern, sealed box subwoofer, is perhaps 8 to 15 millisecond." (If I understand correctly, this delay is relative to the sound coming out of the main speakers, in the absence of some kind of digital delay inserted there by a HT processor.) What is the physical origin of this delay? Is it, perhaps, the time it takes the big voice coil in the sub to get moving?
Whatever the cause of this delay in the sub, how is it qualitatively different from that in the main speakers? In my case, at least, these units also have large internal woofers in sealed enclosures? Wouldn't their group delay in the base range be similar to that of the sub? If so, I'm already living with a group delay in these internal woofers, relative to the mid-range and highs; so how does adding a sub-woofer make this any worse?
I must be missing some essential factor here... -- Clark2
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