I have noticed that PS Audio FR10s and FR5s have pretty low sensitivity. Is there a sonic benefit or other reason for having a lower, say 86 db and below sensitivity for a speaker? I am asking because higher sensitivity speakers, especially in the 90db+ range can play louder and people also like to power them with low wattage tube and class A amplifiers. Full disclosure… I own Spendor A2.2 speakers which have a sensitivity of 83db. They sound good to me. I am just wondering if a company like PSAudio would seek out the lower sensitivity of speakers like the FR10 and FR5 or if that is just the way it worked out when they designed the speaker and got it to sound the way they wanted it to. Thoughts?
The latter; I can’t imagine that any company would have low sensitivity as a design goal.. Low sensitivity is a product of many other design goals.
83dB, huh?? Sounds like the Stax e’stats I owned decades ago.
I’ve discussed this at length in other parts of the forum but there are trade-offs in loudspeaker design between sensitivity, and bass extension. For a given box size, there is a significant trade-off between bass extension and sensitivity. This was encapsulated in Hoffman’s iron law.
Back when 15-25 watt amps, the 1-watt sensitivity of speakers was critical and it was accepted that speakers that play low bass would be very large. However, we now have >100 watt amplifiers at low prices and trading a few dB for an extra octave off bass extension can make sense for people looking at compact, full range speakers.
Remember also that the large signal non-linear behavior of the speaker dominates maximum output, not low power performance. You can have a speaker with 3 dB less sensitivity that plays 6 dB louder, because distortion limited output is a function of large signal behavior of things like power handling, cone area and displacement (BL, compliance, and driver self inductance versus excursion limits), not 1 wattsensivity.
Because of the lack of understanding of this and a lot of potential customers assuming that “more number better” many manufacturers misstate their sensitivity or make speakers with very low impedance (to game the sensitivity spec, as sensitivity is rated at a fixed voltage and lower impedance speakers draw more current and dissipate more watts but raise the rated voltage sensitivity). Our speakers are accurately rated where some manufacture are overstating sensitivty and bass extention numbers radically