A recent “Paul’s Posts” about moving air got me wondering how altitude / air pressure affects speaker reproduction. I imagine greater excursion is required as altitude increases to achieve sea level loudness, but deeper thought brings on brain melt.
If there is a tangible relationship, how does FR series development compensate for those who don’t live at Boulder’s altitude?
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It seems to me we should expect a proportional relationship between air density and spl.
The means to compensate for that is your volume control.
Turning it up will compensate for volume, but I’m curious about the tradeoffs, if any. Does higher excursion for a given spl result in distortion at lower volume? I also wonder if drivers having to travel further to work their magic reduces their resolution. Or maybe it doesn’t make a practical difference.
Obviously Chris Brunhaver would be the one to answer these questions.
But just intuitively, turning up the volume, which works the drivers harder, improves resolution at least in my case.
Some speakers, including my Meridian DSP9, have a recommended atmospheric pressure range in their specifications, just like a stated ambient temperature range for proper performance.
I am guessing that the 2,000 meter altitude limit from Meridian has more to do with exceeding the operating temperature inside these active speakers, with six power amplifiers inside. At 7,400 feet, they run warm here in the mountains, but not hot.
Do you really think that the Aspens are designed for Boulder’s altitude?
My speakers always sound better when I’m high.
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There is a small difference in performance with changes in altitude and temperature etc. Here at Boulder, CO altitude (5400 feet / 1655 meters), you gain 0.5-1 dB of sensitivity on speakers and there is bit less damping. Resonance of the woofer shifts a few percent too but not enough to worry about or really be noticeable.
Good stuff Chris. Thank you.