"-As you move 1M or 3.275' from your speaker, the spl will drop by 6dB."
That's a point source speaker. A line source speaker is only 3db.
And isn't that 'at double the distance' for either one not 'per meter' like seems to be implied here my Max and Sean?
Meaning -if you're 2 meters away from a point source and it's 86db there, then it'll be 80db at 4 meters away, not at 3 meters. Right?
"-Sound Pressure Levels of 80 dB can damage your hearing over time."
Really?? I think that SPL level is low. Where did you get that from? We'd all have hearing damage from all our speakers if that was true. And it'd be pointless for any of us to have amps that put out more than 1 Watt is we valued our hearing.
"-In fact, orchestra members can suffer hearing damage, so it is not just a problem with rock and roll."
True, but both get MUCH louder than 80db and why that hearing damage prob. comes up.
Great chart of the fundamentals, but this line?....
"-These frequency ranges are the "natural" frequencies and do not include harmonics (higher and lower over- and under-tones which are said to make music sound like "music")-"
It makes it sound like it's a 'rumor' that harmonics matter.
Harmonics ARE greatly important. 100% as important as the fundamental -which then greatly effects this freq. chart.
Cymbals can go out to 100,000Hz (not that we can hear that or would want to -I still don't understand why some speakers try to recreate these inaudible ranges when the only thing it can do is damage the audible range we actuall NEED them to play).
Harmonics are what makes any two instuments playing the same fundamental tone sound like two diff. instuments.
This issue of Harmonics is what makes charts like these so tough to learn anything from -though this chart IS totally accurate.
Take a Violin....
196Hz to 3,136Hz.... ok, but it's the harmonics that make a Violin sound like a Violin and not a Piano or a Clarient playing the Exact same notes.
(As stated already) Harmonics are multiples of the main frequency above and below, so w/ almost ANY instrument multiply and divide these fundamentals a few times and you'll see we're talking about a LARGE audible range when you include a few orders of Harmonics.
I heard (I'm not sure though) that harmonics of some instruments can sometimes be louder than the fundamental tone even.
Talking about instruments and freq., but ignoring Harmonics is pretty pointless.
Take a look at the vocal ranges...
Pretty much all of them are under about 1,000Hz on the chart (again.. that's accurate for the fundamental)...
A newbie might look at this chart, and think then that the tweeter in whatever speaker they own is 'not doing anything' when a voice is singing (or 'hardly doing much', or something like that).
My current speakers are 2-ways and cross at about 1,200Hz. I can unplug the woofer section and still totally hear any vocals in any song. They're clear and detailed...there's just no weight to any of them.
Plugging in the woofer section and unplugging the treble section, I can still hear the vocals, but this time there's no detail to any of them. Like they're all muffled and lifeless.
Hard to put a 'percent' on what I hear from both sections... but it sounds about 50/50 to me from woofer and planar treble sections even though technically... the 'fundamental tones' of voices are mostly always coming from the woofers only.
I've never seen a chart that added harmonics onto the list and showed how strongly they effect the actual instrument that's named on the chart.
If anyone can find one like that... I think that'd be great.
As for what's Bass, Mids, and Treble... there seems to be two 'camps'....
The 'typical speaker driver camp', and the 'audible octave/musical instrument camp'...
jpq pretty much listed the speaker driver version going by the idea of where a typical dome tweeter crosses over (~2500Hz), and how low a typical midrange cone usually runs down to be crossed w/ a bass cone (~250Hz-500Hz).
The other 'camp' divides up the three ranges in fairly balanced full octaves and ignores what typical speaker drivers can or can't do.
(found here at S'Phile... http://www.stereophile.com/fullarchives.cgi?50
along w/ lots of other good info.)
Bass ~20-160Hz (3 octaves).
Midrange ~160-1300Hz (3 octaves)
Treble ~1300-20,000Hz (4 octaves)