Low Efficiency Loudspeakers
A Low Efficiency Floor standing Loudspeaker
For a long time now most loudspeakers being sold are of low efficiency. All loudspeakers need to move in order to reproduce the music fed to them. They all are subject to Newtons First Law of motion.
Low efficiency designs have been adopted as stiffer cones are less subject to resonances and it is easier to achieve a the holly grail of a 'flat frequency response'. The big lie is that low acoustic efficiency hence less acoustic output can be simply solved by using a higher power amplifier.
Some designers use loudspeaker enclosures such a horn loading, or a transmission line to increase the acoustic efficiency of a loudspeaker of low efficiency. In this way the lower efficiency can be overset. Many loudspeakers builders however are not using enclosure designs that boost acoustic efficiency.
So what is the big deal, you just hook up your low efficiency speakers with big grunty power amplifiers and the 'job is done', they play plenty loud! Yet there is as the saying goes 'no free lunch' in using lots of amplifier force to get loudspeaker moving there are sonic tradeoffs that a high efficiency speakers fed by a quality low power amp such a triode amp doesn't make
Two qualities that can be experienced with a good high efficiency system is better dynamics with ease, the music sounds less forced, more natural. Despite claims made by low efficiency loudspeakers designers some high efficiency designs (as were popular in the past) can have superior musical resolution. The timbral qualities of instruments are resolved in a way that sounds more natural and less sterile. The music sounds more as an organic musical whole rather than a collection of sounds.
Low efficiency speakers can often do sound harder, more constricted and less like real music. At their worst they are darn boring. The idea that low efficiency speakers have sonic advantages is in the real word in most cases a lie.
Those manufacturers that recognize the sonic comprises of their design and have boosted the acoustic efficiency of their design an by using enclosures that boost efficiency. While these optimized lower efficiency loudspeakers still might not equal all the qualities of the finest vintage designs they may still be worthy of consideration. There are also still some designers that make high efficiency loudspeakers.