'..on paper, a 91db sensitive speaker should develop 91db SPL at one meter (about 40 inches) with one full watt without room reinforcement.'
True if speakers are 8 ohm but for 4 ohm speakers the number is more like 88 dB (91-3).
Which watts are the right watts in SS amps?
Thanks for the concerned thoughtful input so far. It is sincerely appreciated. Sorry. My bad. I’ve been speaking in general terms as no actual decision has been made yet as to which amps or which speakers are getting married. Given the fact I’m doing a lot of research and a goodly bit of speculating, and am flexible on which ones to pair up, I felt only certain parameters were necessary for determining the range of suitable power for a given load and specific speaker brands & models were not concerns I listed the amps which intrigue me. All of which push at least 200wpc into 8 ohm loads. Most will at least say they’ll double with imp halving except BAT & ypsalon. Some offer 300wpc at 8 ohms. Gryphon lands outside normal amp criterium with their dual mono amps base model pushing 150 @ 8, hteir middle unit is 160wpc @ 8; and their top model which is likely well off the table for me, is 175 wpc @ 8, and all double into 4, and then again into 2, and Gryphon boasts doubling continues into 0.5 ohms at 5K wpc in their top unit. All models offer Class A operation in 3 variable stages of 25, 50, or fully Class A, more or less in each amp, respectively. Slight variations occur depending upon model or better said, $$$$$.. Curiously, the two I envy most have reported similarities in their power outputs into 4 ohms at 320wpc. Ypsalon Alieus and Gryphon Coloseum. However, ONLY Gryphon is actually doubling as Impedance halves. Ypsalon does not. As well, both have more than substantial banks of reserves in their Cap storage. More than substantial. In no real order the speaker short list is: KEF blades, I & II, either or. VA Listz or Music either or. Wilson Sabrinas, Sashas, either or TAD Evolution one Longshots if found used: Magico S5 latest ver? Lanch 7? Wilson XLS ? YG ? Eggelston Ivy, andrea II & III. Of current production, I bleive all are 4 ohms. TAD & Wilson are lowest sens at 88 & 87db, respectively. ONLY Egg Andreas are above the 4 ohm barrier. The balance of the lot are 90 – 91db. Party level listening is NOT my gig. As said. Maybe a song or two now and then. Usually I’m reasonably sane and do not push things I’ve paid a lot of money for unless you can pour fuel into them… and those days, sadly are well behind me.. LP is usually set in an equilateral triangle and speakers are normally 8ft. apart, give or take a few inches. This will change but not quickly so it would be a decent rule of thumb.. Hope this helps. |
Sorry @georgehifi , what is EPDR? I looked at the Stereophile measurements (which I do trust, unlike the subjective reviews), and while pretty bad for a full-range dynamic speaker, I only see a drop to 2 Ohms in the bass, with a moderate phase angle: https://www.stereophile.com/content/wilson-audio-specialties-alexia-loudspeaker-measurements This is certainly an example of a hard-to-drive speaker however. |
From my real world experience, when I'm looking at the VU meters of my 250 watt/ch power amp, even at loud listening levels, they stay around the 2.5 watts to 25 watts range (MacIntosh MC 252), hovering more towards the 2.5 watt gradation. But my first amplifier, the Peachtree Decco, a 50/channel amp, had a lot of trouble driving my Dynaudio speakers (86db). The Dyns were much less efficient than my current Legacy speakers, but still, the Decco was struggling to drive them, so obviously it wasn't really able to output clean 50 watts peaks, or even constant 30 to 40 watts as that should have been enough to drive the Dyns in my smallish room to loud levels. That's why the stated specs do not matter that much, and how the amplifier is built matter a lot, IMO. |