Sometimes Hard to Drive Speakers are a Gimmick

WHY?

today high powered amplifiers which can put power into low impedances are everywhere

So most loudspeaker designers simply don’t care it is not a consideration

and most high end loudspeakers will be used with the appropriate matching electronics

today a high powered powerful integrated can be purchased for1500

a Nuprime ida9 can put out400W (8 Ohms), 500W (4 Ohms) so that means under 4 ohms the amplifier can still be putting out power 

as long as you have adequate cooling most amplifiers will have no problem and even in the case of a low impedance dip it still depends on the frequency content, amount, and duration, of that signal

take away not the same issue with most modern high quality amplifiers.

Many amps can drive difficult loads but that isn’t the same as saying they are sounding their best while doing so. For one thing, distortion is higher. It may not seem like much, but since our ears are tuned to using higher ordered harmonics to sense sound pressure the slight increase in distortion is heard as a less relaxed, less authoritative and less detailed presentation. 

Put another way, if you want the most out of your amplifier dollar investment, it will be best served by using a speaker that is easy to drive and more efficient. Amps sound best when they loaf for a living rather than working hard. 

I don’t think speaker designers make speakers harder to drive on purpose so much as they just don’t know any better because they don’t also design amps. 

Having spent much time in the industry (and yes, I read everything in this thread), I feel it is absurd to think that speaker manufacturers are playing games to make their speakers more difficult to drive, with the sole purpose of selling higher powered, higher current amplifiers. Speaking with designers over the years, they try to get the most out of their designs, within their designated price point, to sound a specific way to their satisfaction. Most speaker designers I have known, were never happy, even after a product release, as they are always striving for "better", and this relates to other product categories that we listen through. I have generally been disappointed listening to speakers that are inefficient and hard to drive, even using amps like Krell, as loudness and dynamics were always important characteristics for me when listening. A few examples of speakers I have owned that I found difficult to drive, were Apogee Duetta, DQ 10, AR9, Gale 401, a few Maggies, and I am sure, others. In the meantime, I have always had a set of Lascala, CW or Khorns (when I had appropriate corners/wall structure). Hearing compression from a speaker is a characteristic I am not fond of (amp clipping is another), and my current pair of Lascala I find extraordinary in this area, not to mention a very true to the music bass reproduction. I have a wide range of amplifiers (most have been sold, but still have 20 or so), from ONE wpc to hundreds of wpc, and surprisingly, they all sound dynamic, which is because of the LS. I listen above 100db peaks, and this is what I like. My ears are not damaged, for all of you sceptics. I expect energy and excitement, when I listen, and this has always been me. In a post I started a day or 2 ago, I made it a point of saying that my system meets my "listening needs, wants and desires". Sorry for my rant, but it does pertain to the ops thread. My best, MrD.

There is no evidence that these harder to drive speakers were designed with this intention. In fact nothing you have provided shows anything other than hard to drive speakers exist. 

Notice how every response does not take your premise seriously. As in a definitive "makes no sense". 

I think the reason behind low impedance speakers is the false belief that more power is always better. I learned a great deal from Ralph at Atma-sphere regarding this and other topics. Also have yet to talk with an amp designer (S.S. and tube) that didnt feel their amps sounded better driving higher impedance loads and more benign curves.

You are not going to make any headway on this issue because you are wrong.

I like large amps with high wattage because they do loaf along and are not pushed to clip as they are not being driven hard.big klipsch,michi m8, hegel h30a,big mcintosh all work well for me. I also like electronic  cossovers. Enjoy the music and the design. I also like ribbon planar speakers.

I like the original sterophile review that talked to the designer of the saloon one revel.the platform moved the speaker around to test the soundfield of the speaker. I can't began to keep up to money and technology like that.