First, thanks to @b_limo for posting the DeVore video. I hadn’t seen that before and it is the best explanation of the relationship between sensitivity and impedance I’ve ever seen.
Several good answers to the original OP question but I wanted to add my own experience. For some reason I’ve been attracted to the sound of low sensitivity speakers for as long as I’ve had this hobby. It goes back to a pair of Large Advents that I bought in the 70’s after I heard a friends AR speakers. In a trend that has lasted my whole audiophile life, I invested in amplifiers that would drive difficult speakers. After I got my Advents I bought the biggest Marantz receiver they made (2325). Then I upgraded to an Adcom GFA 555.
When I upgraded the Advents in the early 90’s I listened to over a dozen models and I definitely preferred the less sensitive candidates. I settled on a pair of Mirage M3si which have an 87 db sensitivity. Then I upgraded my amp to a Krell KSA 300S. A few years ago I snapped up a pair of Thiel CS6 that a friend had for sale. These speakers driven by my monster Krell make some of the best sound I have ever heard anywhere.
When I went to AXPONA and the Tampa Show in 2018 I realized that I seemed to prefer speakers with lower sensitivity over those that were very sensitive. I didn’t hear a setup using a single ended tube amp that I lusted after. And I concluded that horn speakers aren’t my thing. They do some things very well but overall they just didn’t light my fire. But I can completely understand why some people love them.
My point here is that the sound resulting from the tradeoffs that low sensitivity speakers incorporate appeals to me for some reason. For the last 40 years I have been willing to invest in the amplification to drive these speakers and I’ve never regretted my decisions. Bottom line, high sensitivity or low sensitivity is not better or worse, it’s one of the many design decisions that speaker engineers make. Once they go a certain direction they optimize their design for the sound they want and sometimes that leads to low sensitivity and low impedance. I happen to be one of those audiophiles who is willing to suffer the cost and back problems of having an amp that will drive these things.
Several good answers to the original OP question but I wanted to add my own experience. For some reason I’ve been attracted to the sound of low sensitivity speakers for as long as I’ve had this hobby. It goes back to a pair of Large Advents that I bought in the 70’s after I heard a friends AR speakers. In a trend that has lasted my whole audiophile life, I invested in amplifiers that would drive difficult speakers. After I got my Advents I bought the biggest Marantz receiver they made (2325). Then I upgraded to an Adcom GFA 555.
When I upgraded the Advents in the early 90’s I listened to over a dozen models and I definitely preferred the less sensitive candidates. I settled on a pair of Mirage M3si which have an 87 db sensitivity. Then I upgraded my amp to a Krell KSA 300S. A few years ago I snapped up a pair of Thiel CS6 that a friend had for sale. These speakers driven by my monster Krell make some of the best sound I have ever heard anywhere.
When I went to AXPONA and the Tampa Show in 2018 I realized that I seemed to prefer speakers with lower sensitivity over those that were very sensitive. I didn’t hear a setup using a single ended tube amp that I lusted after. And I concluded that horn speakers aren’t my thing. They do some things very well but overall they just didn’t light my fire. But I can completely understand why some people love them.
My point here is that the sound resulting from the tradeoffs that low sensitivity speakers incorporate appeals to me for some reason. For the last 40 years I have been willing to invest in the amplification to drive these speakers and I’ve never regretted my decisions. Bottom line, high sensitivity or low sensitivity is not better or worse, it’s one of the many design decisions that speaker engineers make. Once they go a certain direction they optimize their design for the sound they want and sometimes that leads to low sensitivity and low impedance. I happen to be one of those audiophiles who is willing to suffer the cost and back problems of having an amp that will drive these things.