Is the most efficient speaker the best speaker?


Is the most efficient speaker the best speaker -- all other things being equal?
pmboyd
The answer to this question will be based on your personal set of preferences. There is a clear differnce between SET's, higher power SS amps, horn and cone speakers.

Personally, I have rarely heard a higher output Class A/B, SS amp I could live with. The only exception is an amp I could'nt afford, the Dartzeel integrated. In general, I find the set of choices implicit in a higher powered design, produces a sound I dislike. I like tubes and SET's in particular. On the other hand, I have'nt found a Horn speaker I have enjoyed, which means I am not going to find a speaker with 100+ DB sensitivity.

My choices then, tend to be limited to conventional cone speakers of higher sensitivity, with higher output SET or other Class A Amp. I am willing to accept the loss of base extention you tend to find in cone speakers about 92 to 96DBs, as I am a classical, Singer Songwriter, Jazz kind of listener. So, I am using 96db sensitivity Daedalus DA_RMA's with both a 20watt Ayon Spark SET and 50watt Class A hybrid, Pathos Inpol. This combination is ideal for me, it won't be for others with different priorities. It also means there is'nt an ideal combination, just as others have mentioned, a particular set of compromises in Speaker and Amp design, that suits your needs. Vive La difference
Magfan, there are other posts, but IMHO this one might be the best example:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1264342155&read&keyw&atmasphere+chaos+theory&&st50
Hi Unsound, thanks for the greater specificity.

You have not offered any proof that: "Now the Power Paradigm offers the possibility of being that much closer to the music."

Here's how that one works: The Voltage Paradigm places its highest regard on flat frequency response. This is as close as the VP gets to obeying hearing rules. Now what we are talking about is the idea that the amp can make constant voltage with respect to load- that gets you flat frequency response when the amp is used with a speaker that has box or driver resonance as part of its impedance curve (in a nutshell). What this *ignores* is the fact that the human ear hears non-clipping harmonic distortion as frequency response variation. In fact the ear is just as sensitive to this if not more so then *actual* frequency variation.

This is why two amps can measure identical bandwidth on the bench, but one can sound bright while the other does not- it has to do with distortion.

So if the amp is *required* to use loop negative feedback either in pursuit of a low output impedance so it can have a constant voltage characteristic, or in pursuit of low distortion (the other 'looks nice on paper' spec) the result is that the amp will sound brighter since the 5th, 7th and 9th harmonics will be distorted due to the feedback. It happens that the ear uses these harmonics to measure how loud a sound is. So distortion in this regard of slight, barely measurable amounts is audible due to the fact that this is one of the ear's most sensitive aspects: our **survival** might depend on it!!

IOW, the use of feedback violates a fundamental hearing rule- how we detect the volume of a sound. This is why I say that the VP is made to look good on paper, because it ignores this fundamental process of human hearing. Now if you can achieve low distortion and constant voltage without feedback, then you might have something. I know of only 2 amplifiers that can do that. I regard this as the cutting edge of technology and is the frontier where development can still yield results. If this obstacle can be overcome then I'm all for it.

The way the Power Paradigm works is that it acknowledges that reducing the distortion can be more audible than flat frequency response, and that certain distortions are more important in this matter than others. IOW, it is placing a greater value on the hearing rules than the Voltage Paradigm is. To this end, loop feedback is eschewed due to the facts I previously explained. To maintain frequency response due to interactions with the speaker, different crossover techniques are used. To reduce overall distortion, non-feedback methods are employed, although depending on the designer a greater or lesser emphasis may exist regarding the presence of the lower orders (2nd, 3rd and 4th, BTW the 3rd is the only odd ordered harmonic that the ear does not hear as harshness- it regards this harmonic as musical like the 2nd and 4th).

Personally I don't like the presence of the even ordered harmonics as they contribute to 'tubey sound' which I regard as a coloration (remember, the ear hears harmonic distortion as frequency response variation and this is an example). They can be eliminated by fully-balanced circuits.

Or that: "OTOH the Voltage Paradigm is all about looking good on paper (IOW pays little attention to human hearing rules), which are ears could give a damn about."

Now I did explain some of this already but in a nutshell the Power Paradigm holds as its highest ideal that the more the equipment is able to obey human hearing rules, the more its reproduction will sound like real music. The logic is obvious...

The Voltage Paradigm by comparison holds the value of flat frequency response and overall lowest distortion as its ideals, regardless of the fact that in doing so a fundamental hearing rule is abused. That is why I say it cares more for appearance than sound.

or that: "So going to higher efficiency is clearly an access to transformation in sound quality. Of course its better!"

I already commented in other posts- this is the one about higher efficiency drivers being more reactive. Amps with feedback don't react well to this- this is one reason why horns sound shrill and honky when used with amps that employ loop feedback (again, in a nutshell).

The point with this comment is that highly reactive drivers, if you want them to work right, are best used with an amplifier of little or no feedback. So the interaction between the amp and speaker is good, and the amp will not make the distortions that the ear finds to be the most objectionable (ideally- there are good and bad amps IMO regardless of what side of this debate they are on). That is the transformation- the access where the line between a good sounding stereo and a stereo that sounds like real music is crossed. IOW one has 'good' specs but the other is designed to obey human hearing rules. That difference is audible and is measurable too, once you know what to look for.

Two side notes:
1) all headphones are Power Paradigm technology.

2) Its important to point out that with a lot of traditional horn speakers, the crossover will not work very well with a modern transistor amp. The reason is that the crossover rules for a Power Paradigm speaker have different assumptions than those of a Voltage Paradigm speaker, based on the way the amp behaves. The result is that a horn running with a transistor amp will often be playing out-of-band information at volume levels that the designer did not have in mind at all!
David12,
Very well expressed post, I imagine your system sounds very natural and emotionally involving. Enjoy!
Atmasphere,

I tend to agree with most of what you've said. In addition to these points I'll add that the distribution of the harmonic spectra is also important: their amplitutes should be inversely proportional to the order of the harmonic(ie. 3rd>4th>5th>...>Nth), in a more or less linear fashion. I don't for example like to see the 6th harmonic being highger than the 5th even though the even order 6th is the more "bening" one.

One of the best articles I've seen on HD perception (link bellow) is by Lynn Olson. For those not too technically inclined skip through to the middle where the heading is "The Sound of Different Harmonic Spectra". Also, for those believers in power cables there's a little bonus in the form of a technical explanation as to why power cables do indeed make a difference in many cases.

http://www.nutshellhifi.com/library/FindingCG.html