For the New Year - I will be refitting my 4 Pi Towers with Delta Pros, and hopefully building a Transcendent OTL amplifier.

Time to pause, and ask a question. What are the benefits of high efficiency speakers over low efficiency. Why isn't the mass consumer space using high-efficiency drivers.

Also interested in what some of you did during 2004, and your plans for 2005?

Thanks
Hakn

I think the reason why folks don't have "high-efficiency" drivers in the average home market is because:

a)they like cute little cube speakers that sound just like "little POS", cosmetic looks are higher priiority than sound!

b)is because the higher efficiency speakers are more revealing of the sound sources, and that would show the inadequacies of their mainstream amps/recvrs which are mass produced across the great pond, compared to our SET's which are more costly than the entire "stereo-in-a-box" type systems(which include "cute little cubes" again).

c)decent high efficiency drivers usually cost more than the "made by the thousands" stuff across the great pond

d) most importantly you must understand that for "most" folks, the quality of audio is not a critical need. Only a few of us(me included) actually spend time dedicated to "audio only", sit in the perfect spot(the sweet spot), and spend money like I had it to burn(sometimes missing meals and other luxuries) to get the ultimate in sound reproduction according to what we think the best sound should be like.

My apologies in advance to the Bose and other fans who like the little cute cubes, but just remember, just like engines, there really is no substitute for cubic inches!!! Little speakers sound just like little speakers. You can't change the laws of physics.

Ron (fan of refrigerator sized speaker systems)

Other than that, I don't see any purpose. It is also true that it is much harder to get a flat frequency response from high eff speakers, i think becuase of the limitations of materials that can be used to make high eff. speakers.
Just my beliefs,as of today (they may change asi learn more) mostly empirical.
-akhilesh

As an example, the first drivers I ever saw that used shorting rings were prosound units. That made them waaaay better where distortion was concerned because for one thing they were very efficient, so required low drive levels for a given SPL and for another thing, they resisted flux modulation distortion, so even-orders were like 20dB less.

Now days, I think there are some high quality low-efficiency drivers. High excursion woofers have relatively low efficiency because the geometry of the coil and magnet makes high excursion and high flux density mutually exclusive. You can increase magnetic strength, but if the flux is spread out over more space to make high excursion possible, that reduces magnetic density. This requires more power in the coils to move the diaphragm greater distances. So even if the build quality is there, the efficiency is not.

I suppose some of those high-power, high-excursion designs can be made to provide high output, and maybe low distortion. With greater power, they can be expected to provide high SPL, which then means it is possible to get them to produce high dynamic range. There is the compression issue to deal with, but I am not closed minded that it couldn't be done. So I suppose there are possible solutions using low-efficiency designs that provide high dynamic range and low distortion.

But most low-efficiency designs aren't particularly impressive. The newer high-excursion woofers of the last ten years or so are a possible exception, but most home hifi speakers in the 85dB-90dB range are just average devices with 100dB maximum power limits. That's where high efficiency speakers start, with a watt or so, just loafing. I have personally never heard a low efficiency design that was of exceptionally good quality. So I guess that's where my observation ends.

• Do more sensitive drivers offer less distortion at "normal" listening levels?

-akhilesh