How important is the efficiency of a speaker to you?

@rauliruegas I think we need to be more clear as to what we are discussing when it comes to lower sensitivity. There is little question that a lot of great speakers are in the less efficient camp, meaning that they are not in the 100db/w mode, but closer to 85db/w etc., These very same speakers may drop down into the 3-4 ohm load in the bass, which might present a more challenging load to some amp designs, but like pointed out, with a sufficiently beefy power supply, will still work fine. These are not really the speakers that I am talking about here..  

@daveyf This makes more sense. Your original post seemed to suggest your dissatisfaction with speakers not efficient enough for “your” tube amp vs speakers that are inefficient way below the average speaker.

I’ve demoed many good/great speakers at brick n mortar and audio shows, but very few subjectively “resonated” with me. That’s why I thought it a good thing that the OP found such a speaker.  Unfortunately, the speaker requires significant power. Maybe a tube pre + SS amp might work out economically and sonically.  Good luck with your search.

Btw, I remember listened 4-5 times in the past the original Wilson Watt and this is a fantastic true monitor not high efficiency as a horn but measured 91db and this Watt has a problem for any amplifier ( tubes forbidden with ) at 1khz its impedance surve measures 1ohm and near 2khz 0.32 ohm . IN those times the preffered amps for it were Krell and Spectral.

This is mostly incorrect.

At the time this speaker was made, the national sales manager of Wilson was using Atma-Sphere OTLs in his home system. The Watt was an easy load for any tube amp (David designed his speakers using ARC amps and often showed with them; my first exposure to Wilson was at the ARC factory).

That 1 (or 2) Ohm load was at about 2KHz where there wasn't a lot of energy. The tweeter had a resonance problem and so there was a 2KHz trap that presented the amp with a low impedance, thus knocking out the resonance pretty well. This worked great with tube amps! Not so much solid state, as solid state amps would often make more power into a lower impedance rather than less.

@rauliruegas wrote:

Well , that large size is not exactly typically " because depends on the kind of drivers other than horns and an example are my ADS speakers that yes are " large size " but the size is due that the speakers can goes down to 16hz through two 14" acoustic suspension woofers but today I have the ADS from around 100 hz and up and the soft domes ( silk ) acoustic suspension 2" for the mid-range and 1" for the tweeter ( one a top the other:nearest as it can be. ) needs a very small " box space " due to its very high gauss magnets ( are not vented and non-ferrofluid. ) around 24k in the tweeters and 18K in the mid range, both drivers made it in Germany for ADS and its efficiency is 95db ( almost a horn . ). Unfortunatelly the drivers manufacturer just does not exist any more.

True 95dB sensitivity is certainly quite efficient compared to the general norm of speakers (that are closer to a typical 85dB’s, making for a ~10dB difference here), and in conjunction with your ADS L-2030 speakers extending as low as they do with dual 14" woofers per cab there’s no escaping the implications specified by one Mr. Hofmann and the following larger size.

My efficiency context is higher, and once horn-loading becomes necessary/preferred, not least when you want them to act like horns in their entire frequency span, up to very large size is unavoidable. In my setup context I’ve not yet fully exploited the efficiency factor (save for the midrange/tweeter horn); if I wanted at least ~105dB sensitivity top to bottom (i.e.: 20Hz-ish on up) it would require non-truncated front loaded horn subs and similar type horns for mid bass (but with the fewest and low degree horn path bends) or star quad 15" direct radiators, which is a significant upgrade size-wise below ~500Hz easily by a factor of 2 compared to what I have now. Having said that my corner mounted tapped horns subs takes further advantage of significant boundary gain (1/8 space), and so the least efficient driver section is the midbass bins sitting at ~98dB’s (hardly slouches, also considering they’re high-passed).

Trying to make some sense of the madness one could ask whether an efficiency that high is really necessary in a home environment. Obviously that’s up for each to assess and decide, but to me at least it isn’t about bonkers SPL’s; it’s about maxing out the sonic potential of horns and aiding the best integration, also with direct radiating sections. Ease of load of the amps, not least with active config., is another boon. Indeed sufficient headroom is a prime takeaway here (regarding both speakers and amps) - that is, it’s that it actually matters, and far more than people seem to realize.

What keeps most audiophiles (who’re already inclined towards high eff.) from venturing into very high efficiency and directivity control in the entire audio band - with all that entails - is mostly about large size becoming an obstacle, be that aesthetically or practically. However it’s also about a particular mindset, because it requires of one to acquire pro segment, DIY or vintage gear when such large designs are hardly available domestically, not least at less than astronomical prices. It’s a radicality of approach few (but perhaps more and more) are willing to pursue.

Kudos on your setup, btw.

@deep_333 wrote:

Generally, high efficiency speakers have sounded unrealistic. What do the masses think of and come to conclusions when they’re thinking high efficiency? There it is, it can be attributed largely to bad actors like Klipsch, who’re all over the place and generally made plenty of flawed speakers with a couple of exceptions perhaps. It also seems like any other jester will come up with some horn speaker whilst tinkering in his garage, bring it to shows, etc and they’ve sounded stupid.

Nevertheless, when you buy a high efficiency speaker from guys who really know what they are doing, they seem to sound truthful. ...

I agree.

@lonemountain wrote:

Very good point and great example that there is more to know about a speaker than a 1w/1m spec. Could a 86dB 1w/1m speaker with a very flat impenace curve outperform a 91db 1w/1m speaker with a wildy changing impedance curve? Yes.

That’s not really saying anything about the argument of high efficiency, in fact it goes without saying. Your effort to isolate a high sensitivity rating as a singular, non-determinant factor in no other context than itself is just trying to serve an argument against it, and not seeing it for what it can do in the greater scheme of things. Come on :)

Over the years I have found that lower power amps (35-45 wpc) always sound better to my ears. That makes low efficiency speakers (83-87db) a non starter for me

Well, D.Wilson ( paw, unfortunatelly. ) was not so stupid and " deaf " as his national manager and he used only Krell/Spectral amplifiers with the Watt/WAMM speakers to monitoring all his great Wilson Audio recordings.

"

The manual suggests that direct-coupled Futterman and similar tubed amplifiers are inappropriate, but gives the OK for other tube models when used on their 4 ohm tap. I have to disagree. A 1 ohm load severely limits the output power from a tube amplifier. For example, a 100W output (17dBW, 8 ohm) into a 4 ohm load will typically fall to 7dBW, or 10W in level terms, when faced with 1 ohm. Simply, this means that the amplifier will clip 10dB earlier if a strong musical signal appears at 2kHz, which is not unlikely, since this frequency is well in the main music power band.

Let us also assume a typical case where the tube output impedance and cable loop are limited to 0.4 ohms. Overall there is a loss of 0.8dB over the whole range, but at the 2kHz minimum impedance the loss increases to nearly 3dB, this inducing a dip in acoustic frequency response of 2.2dB which may well alter the sound of the speaker.........................................................Last and by no means least, there is the matter of that awkward load impedance, and the corresponding, almost unforgivable dip to 0.33 ohms noted on the review pair.......................................................Depending on the amplifier used, there was also a touch of hardness on, or edge in, the upper midrange which was ameliorated by using the Goldmund Mimesis 3 power amplifier and one or two of the other high-current amplifier types such as the Krell. This mid-treble problem was rather amplifier-dependent (due to the impedance characteristic...."

Btw, we have to remember that that 1 0hm and 0.32 ohm at those frequencies is not a discrete impedance value but part of the speaker impedance curve and  the adjacent frequencies and developed harmonics are " touched " too.

Stupid people are all over the world and just fine with me.

R.