How important is the efficiency of a speaker to you?


I went to an audio meeting recently and heard a couple of good sounding speakers. These speakers were not inexpensive and were well built. Problem is that they also require a very large ss amp upstream to drive them. Something that can push a lot of current, which pretty much rules out most low-mid ( maybe even high) powered tube amps. When I mentioned this to the person doing the demo, i was basically belittled, as he felt that the efficiency of a speaker is pretty much irrelevant ( well he would, as he is trying to sell these speakers). The speaker line is fairly well known to drop down to a very low impedance level in the bass regions. This requires an amp that is going to be $$$, as it has to not be bothered by the lowest impedances.

Personally, if I cannot make a speaker work with most tube amps on the market, or am forced to dig deeply into the pocketbook to own a huge ss amp upstream, this is a MAJOR negative to me with regards to the speaker in question ( whichever speaker that may be). So much so, that I will not entertain this design, regardless of SQ.

Your thoughts?

128x128daveyf

@phusis  It is not a myth, it has to do with the low output impedance of solid state amps.

@phusis  It is not a myth, it has to do with the low output impedance of solid state amps.

Flea watt SET tubes produce a lousy loose wet noodle bass, sounds like a sloppy fart. It's not a myth. But, guys who listen to Diana Krall @60db may not know any better. When the bar is set so low, loose fart SETs might indeed sound spectacular for such guys.

Nothing sterile, tonally lean, mechanical or bright sounding about the Brit, I can tell you that, or whatever you’re implying about high power amps sonics.

@phusis The issue is that most amps made using feedback, which includes high power solid state amps, is that the output transistors usually limit the design's Gain Bandwidth Product, resulting in a loss of feedback at high frequencies (depending on how much loop gain is asked of the design). The result is distortion rising with frequency, which seems to be more audible than the actual distortion spectra created by the amp. Class D offers a way around this problem.

Another generality, indeed this one is a myth that has gone on forever.

The issue here is that a lot of higher efficiency speakers are designed for amps with a higher output impedance. Such amps try to make constant power rather than constant voltage; this is not a myth. The Power Paradigm is what was around before MacIntosh and EV started promoting higher feedback in the mid 1950s so as to cause their amps to behave as a Voltage source, allowing plug and play. You might want to read this article for more information.

Flea watt SET tubes produce a lousy loose wet noodle bass, sounds like a sloppy fart. It's not a myth.

@deep_333 You might want to read the article at the link above as well. This is not a myth; its a matter of whether the speaker designer meant for the speaker to be driven by an amp of high output impedance. If so, the bass will not be as described (although SETs in general do tend to have less impact on account of phase shift above their cutoff frequency, which tends to be quite high due to their output transformers).

Can we say then that efficiency in speakers is not the #1 goal?  That the idea that dynamic range is improved or noise floor is changed due to speaker efficiency alone is simply not true?  While there may be examples that support this idea, there are far too many exceptions to make this speaker efficiency issue a universal need?

Brad