Thanks Duke -- very interesting tech point. As you may recall, my speakers are Paradigm S8s (v3). The main difference between the v2 and v3 versions is that the 4 woofers are 3 db more efficient.
Paradigm changed the voice coil and the motor throw distance in the woofers to achieve the greater efficiency. I understand that they also "untapped down" the tweeter and midrange driver to match the woofers. Btw, the tweeter and mid both use ferro fluid to cool the voice coils. I suspect that these changes may have helped to mitigate thermal compression, but I honestly don't know if Paradigm had thermal compression in mind when it updated the S8s.
Last point, admittedly unrelated to this OP, so I'll make this short. You may recall that we had numerous on-line and off-line conversations about the electrical match of my ARC tube amp and the S8s. Two tech points came to my attention later that resolved many of my concerns. The first is that when Paradigm changed the woofers on the v3 and "un-tapped down" the tweeter and mid, the impedance peak at 2KHz dropped from 28 ohms (v2) to 21 or 22 ohms (v3). That's a good fact. In addition, I came to better understand that my amp is NOT a pure Power Paradigm amp because it uses 12db of negative feedback. As a result, output impedance off the 8 ohm tap is about 1.1 ohm. Output regulation is rated at approx. +/- 1.2 db. The stats improve even further off the 4 ohm tap. Output impedance may be 50% to 60% as compared to the 8 ohm tap and output regulation may be as tight as +/- .5 db. So, I've been using the 4 ohm tap and retrained my ears. I think the combo is pretty good after all.
Sorry for the hijack. Feel free to continue this off-line if you have any interest.
Cheers,
Bruce
Paradigm changed the voice coil and the motor throw distance in the woofers to achieve the greater efficiency. I understand that they also "untapped down" the tweeter and midrange driver to match the woofers. Btw, the tweeter and mid both use ferro fluid to cool the voice coils. I suspect that these changes may have helped to mitigate thermal compression, but I honestly don't know if Paradigm had thermal compression in mind when it updated the S8s.
Last point, admittedly unrelated to this OP, so I'll make this short. You may recall that we had numerous on-line and off-line conversations about the electrical match of my ARC tube amp and the S8s. Two tech points came to my attention later that resolved many of my concerns. The first is that when Paradigm changed the woofers on the v3 and "un-tapped down" the tweeter and mid, the impedance peak at 2KHz dropped from 28 ohms (v2) to 21 or 22 ohms (v3). That's a good fact. In addition, I came to better understand that my amp is NOT a pure Power Paradigm amp because it uses 12db of negative feedback. As a result, output impedance off the 8 ohm tap is about 1.1 ohm. Output regulation is rated at approx. +/- 1.2 db. The stats improve even further off the 4 ohm tap. Output impedance may be 50% to 60% as compared to the 8 ohm tap and output regulation may be as tight as +/- .5 db. So, I've been using the 4 ohm tap and retrained my ears. I think the combo is pretty good after all.
Sorry for the hijack. Feel free to continue this off-line if you have any interest.
Cheers,
Bruce