I think that what you have just described is accurate mid-range reproduction, from about 200Hz - 2000Hz. This is the range of frequencies where the human ear is most sensitive and where we have the strongest sense of audio "rightness". If a speaker does not get the mid-range right, the rest is irrelevant.
One of the interesting "fads" right now in high-end audio is the proliferation of speakers with a very recessed mid-range -- and some of these speakers are in the mega-buck category. Some of the high-end audio reviewers seem infatuated with this speaker "sound", whereas several years ago they were raving about speakers that had a very forward, "in-your-face" mid-range quality. A few of the speakers with this recessed mid-range quality also have accentuated high-frequencies that create the initial impression of "air" and "transparency", but after some extended listening you realize that the speaker has poor tonal balance, and it ceases to sound realistic.
Although the audio properties of a speaker are, to some extent, a matter of personal taste, I personally agree 100% with your comment: "If it doesn't sound beautiful, if the instruments and voices aren't naturally seductive---you're not listening to music anymore..."
Since we are all familiar with the TRUE sound of the human voice, it is the best test signal to evaluate the fidelity of a speaker. However, other less accurate speakers may sound better for particular kinds of music. If you listen to rock bands, buy a big boom box like the ones they use on stage. If you listen to dixieland jazz, get a horn midrange/tweeter. I had some very small B&W bookshelf speakers that were great for violin. They were about the same size as the soundbox of a violin. If you must hide the speakers from your wife, get those tiny Bose speakers. If spatial characteristics are most important to you, get some ugly room dividers - sorry..Magneplanars. There is no right answer.
Flat and fast midrange response.
What you said, plus higher efficiency/easy load, plus WAF.
Higher efficiency for flea/fly watt SET/push-pull amps and the rest should be obvious.
For me it's balance and seemlessness.
For me, it's not so much a particular spec or trait but instead it's can I tell the difference, on a recording, between a Gibson and a Martin, a Guarneri and a Stradivari, etc. The most reasonably priced speaker that can do this, irrespective of laboratory measurements, is the one I'd buy.
Try listening to Spendor S3/5's in a small room. I have heard very few speakers that can do what these do. Not for thrill seekers, but if you want to just listen to music and relax....
Midrange, if it ain't right nothing can possibly be.
I use the LS3/5a's on the side along with another full range speaker and for the price and size it would be very hard to beat. It is a good speaker to use for reference to evaluate other speakers midrange as well. Sure there may be others which may have a better midrange but one has to dish out a lot.
To each his own!
The most important aspect is that you like the sound of them and can listen to them for long periods. Flat frequency response over as wide a range of frequencies is important also. Look for bass extension to at least 40 Hz. Decent speakers and good electronics make for a system that is a pleasure to listen to. Go out and audition as much as you can with music you own and take notes. Have fun while you do this too!
Tonal accuracy, as most say in one way or another, and especially in the midrange, as Scott says, is certainly the first thing to get right. For me, though, low distortion is more important. Almost all speakers make a lot of noise and have much higher levels of distortion than electronic components. Driving the distortion level down helps to make voices sound like real life by eliminating the sonic products that you wouldnt hear in an unamplified live performance, like, e.g., material coloration from almost all cone drivers.
Our posts are not in conflict with each other -- accurate mid-range reproduction means, ipso facto, that the distortion is very low. Otherwise, the mid-range ain't accurate...
You are quite correct that distortion is far higher in speakers than other audio components, but since speakers are transducers, there will always be some inherent non-linearity. I personally think that time- and phase-accurate speakers sound better, assuming their drivers are of high quality, than speakers that are not, and they often have the virtue of lower distortion as well.
Well, I didnt think I was disagreeing with you in any material respect, but it depends on how you define accuracy. It is possible to measure a speaker's frequency response, and get a flat reponse, but still have high levels of distortion. Of course, you can include low distortion in your definiton of of accuracy, but I think it best to keep the concepts distinct.
Take a look at the measurements of the Mirage MRM-1 at soundstage.com, equipment archives, loudspeakers,and scroll down, or just try this url
Not real flat, but not a bad frequency response, yet, to me, unacceptable levels of noise and distortion in the bass (where almost all speakers have a problem) and midrange. No real correlation with the FR, they are separate measurements.
I know from personal experience that when I play a 50hz tone through my Harbeths, I hear a 50 hz tone coming out of them. No audible distortion. But when I play the same tone through a pair of AE Aegis Ones, a pretty good little $300/pair speaker, though the spl meter reads about the same, I hear something that sounds more like 58-60 hz because the output includes the fundamental plus some doubling and other distortion components.
The reason I say low distortion is more important is that we adjust to different tonal balances in different venues all the time, so moderate FR inaccuracies are not always troubling (some are), but distortion is always annoying. A frequency response inaccuracy means the notes are played a little too loud or a little too soft (if in the fundamentals part of the midrange). You may not notice, or may not care. But distortion means the wrong note.
Sdcampbell pretty much nailed it...you could have the most liquid top end and the tightest, deep bass known to man...but if the midrange isnt seamless...lotta work for nothing...which is why I assume that in 2-ways for example...the trend towards higher x-overs...3khz and up...is becoming more common...would also agree...the hi end has gravitated towards a more mellow, laid back midrange presentation...which isnt adherently bad...basically what Vandersteen has pioneered since the 70s...albeit without the clever boxless design, phase integrity, and value the Vandies represent(maybe this insnt a good comparison!)...at any rate...the "spatial" midrange production all too common tends to be generated from the speakers and less from the recording itself...again...not a bad thing...but coupled with an exaggerated "hot" treble...can sound artifical over time...just an observation...also...Scott...thanks to your informative responses to my posts and many others....always enjoy your insight...
Many good comments above. I like the description of one of the masters of our trade, Mile Nestorovic. He would always say "The speakers should disappear!" For me this is a requirement. I think that was Jayme's point at the start.
What physical attributes or designs will accomplish this? There are many answers. Major considerations, that often involve compromises, are the bass lower frequency limit and the maximum acoustic level (loudness, room size). (this brings us to what music are we playing, and how loud? - as mentioned by Eldartford).
Interesting that no one has mentioned "sound stage" or "imaging" in those terms. But what I like is for this 3-D hologram to appear at the "front" of the room, and I forget that there are speakers, and the music transports me to another dimension.... This is an illusion, of course, and it requires my participation. Very subjective stuff.
This illusion can be convincing when the speakers reproduce the voice and musical instrument sounds, as described by others above; and also do not call attention to themselves due to distortions, noises or introduced sounds (such as resonances), or compression of dynamics.