[QUOTE=PJK3,Jan 5 2005, 08:00 PM]...and sound waves travelling in a room from multiple sources (don't forget tweeters, midranges, midbass, and subs) are MULTIPLE sources, not the same.

 

30 hz is way low... you're correct. and i thought that chest thump resonance was closer to 60 hz, but i'm not sure of that myself... but i think a bass guitar will get very low... still, probably not in the 30 hz range.

(according to the faq at rec.music.makers.bass - a bass guitar can get down to just below 31 hz. typically, normal tuning puts it around 41 hz. i have no idea what tuning he was using.)

and i am very familiar w/ phase, reflections, cancellations, additions, resonances, etc... and you're correct to say that they have a great affect on how all of this turns out... THAT math, i do have a good grasp on and am very familiar with it... i use it as a basis for my daily work. it's actually relatively simple to work with... i'm sure others won't agree, but...

and for the case of the bass guitarist -- i'm sure that a number of his problems had to do w/ the room dynamics, but with his proximity to the amp/monitor originally -- you'd think it wouldn't matter so much. but the distance did. once we moved the amp and finished the show, we experimented later with various placements. we tried various locations in the room, and all of the 'far away' ones worked, but the close in ones didn't. *shrug*

but how compression waves actually disperse isn't as easy as you might think... and that's the realm we're dealing with... it's in the land of multi-dimensional calculus, differential equations, physics, and fluid dynamics... those subjects would predict how waves propogate within a medium. i've had various coursework in each of those subjects, but it hardly makes me an authority in any of them... so without some serious research, learning, etc. it's not a realm where i am an expert at all...


still -- going back to the whole point of this very enjoyable diversion -- Dave's argument was that bass would sound better in the trunk because of the increased distance. my point was simply -- we're not talking about big enough distances for those subtle changes (if they exist ) to matter.

 

yes...

i'm assuming you're a musician of some sort... in my youth/late teens, i played piano for 8 years. believe me -- a single note struck sets off an almost limitless number of other frequencies on every string that's of a harmonic. not to mention the frame (forget the real name), the piano body, etc. and all dependant upon the materials of construction for the piano.


the piano isn't ever a good example for a 'true tone'. but, God help me, i love the sound of one and still regret the choice to chase girls over playing more.




and while you will have captured the harmonics from a recording -- when using multiple speakers, they do need to be reproduced to sound right (specifically 2 way, 3 way, etc.). because when it was recorded, the harmonics were captured. as they are played back however - one speaker in a set of 3 is only producing the frequencies in its range of operation. without the other speakers working in unison, you'll get no other harmonics outside of that speaker's abilities. so, there is a need for air space (distance) for that blending to happen... to reconstitute the sound as it was originally.

 

i've done some serious looking lately (including some fluid dynamics checking) and some internet research... just don't tell my boss...

for now, i'm going to call this an unknown - maybe it is voodoo and chicken bones, but maybe it is an authentic quantity... i can't seem to find a GOOD realistic reference for this. i've found a number of audiophile commentaries on it, but audiophiles aren't always the best for scientific proof. and i've found some other less biased commentary in both the car audio and pro audio worlds, but nothing really w/ any evidence or proof of the phenomenon.

so, while i highly respect the person who taught me this and my experience has born this to be true -- i can't prove it. which leaves it as an unknown...

didn't mean to make a stir. i still know how i feel on the subject, but it doesn't quite line up w/ what i know... so, until i can research or derive something concrete, the two will have to differ.