Tweeter upgrades?
Jadem6, not sure how much this answers your question but I spoke with Alan Hulsebus of Orca Design concerning Dynaudio tweeters, such as I have in my Duntech Princess speakers. He believes the D-28 and D-28-2 sound identical. As for the more expensive Esotar, the only difference he hears is about 1 dB gain in efficiency, otherwise, "same frequency response, same waterfall, same impedance, same distortion, same power handling, same soundstage."
Since I don't know which tweeter Dunlavy used in your SC-IVa, this may or may not be of interest. I will say that I've listened to a friend's system with the mid-sized Raven ribbon tweeter and find it to be somewhat more airy and detailed than my speakers. Also, I had the opportunity to listen to some JM Labs with their new beryllium tweeter in my system and, yes, it too may be marginally better. However, given the complexity of driver matching and crossover design that John Dunlavy put into my system and yours, what are our chances of making a change that "improves" our high ends?
Jadem6, not sure how much this answers your question but I spoke with Alan Hulsebus of Orca Design concerning Dynaudio tweeters, such as I have in my Duntech Princess speakers. He believes the D-28 and D-28-2 sound identical. As for the more expensive Esotar, the only difference he hears is about 1 dB gain in efficiency, otherwise, "same frequency response, same waterfall, same impedance, same distortion, same power handling, same soundstage."
Since I don't know which tweeter Dunlavy used in your SC-IVa, this may or may not be of interest. I will say that I've listened to a friend's system with the mid-sized Raven ribbon tweeter and find it to be somewhat more airy and detailed than my speakers. Also, I had the opportunity to listen to some JM Labs with their new beryllium tweeter in my system and, yes, it too may be marginally better. However, given the complexity of driver matching and crossover design that John Dunlavy put into my system and yours, what are our chances of making a change that "improves" our high ends?