Old Seas Excel: "Heavy copper rings mounted above and below the T-shaped pole piece".
New Seas Excel (AudioXpress): "A heavy copper ring below the T-shaped pole piece, and an additional copper cap in the air gap".
As far as I know, Audio Technology, Dynaudio, Wavecor and pre-1993 ScanSpeak has a copper sleeve in the air gap, while post-1993 Scan-Speak and Seas Excel (up until now) has copper rings only above and below the air gap. The former has lower distortion in the midrange, the latter in the bass.
It looks like Seas has moved one of the two copper rings, from above the pole piece down into the airgap. This may explain why their new midwoofers has only half the inductance of the older models. The result? A bit lower distortion in the midrange? A bit higher distortion in the bass and lower midrange? Better suited as midwoofers, not woofers?
New Seas Excel (AudioXpress): "A heavy copper ring below the T-shaped pole piece, and an additional copper cap in the air gap".
As far as I know, Audio Technology, Dynaudio, Wavecor and pre-1993 ScanSpeak has a copper sleeve in the air gap, while post-1993 Scan-Speak and Seas Excel (up until now) has copper rings only above and below the air gap. The former has lower distortion in the midrange, the latter in the bass.
It looks like Seas has moved one of the two copper rings, from above the pole piece down into the airgap. This may explain why their new midwoofers has only half the inductance of the older models. The result? A bit lower distortion in the midrange? A bit higher distortion in the bass and lower midrange? Better suited as midwoofers, not woofers?