posted
whats the use, in SPL for the square wave. I've seen some post that mention it, and there's even some tracks on DB jamz whith that. Using square gives a gain in the DB readin???
-------------------- CRX Si 89 SS 1,2 nw, local street 3,4 157.1 dbs 2 DD9915 2 DD Z2 kinetic hc16 batts Iraggi 300 amp alt Posts: 324 | From: SJ Puerto Rico | Registered: Aug 2004
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posted
a square wave containts more power than an equivalent fundamental wave.
there are two schools of thought on the usefulness of this:
1) because there is more power, there is more spl
2) because the power is due to frequencies other than the fundamental frequency, it doesn't matter.
I'm of a very simple school of thought, myself. a composite waveform is not "interpreted" by the amplifier, but instead represents only a sequence of instantaneous output voltage requirements. in the case of an infinite series of harmonics (a TRUE square wave) you have a mathematical item, an instantaneous rise to maximum amplitude (highest voltage) and a subsequent production of current for the duration of that portion of the cycle, then an instantaneous drop to the negative maximum amplitude, and subsequent current production there.
this represents a corresponding force on the speaker based on the electrical input which is the maximum possible for a given frequency.
however, as this is a real world situation, an amplifier won't respond to square wave rises and falls instantaneously, but instead will be limited by its slew rate, and a sort of rounded off effect will be had.
does this really increase your spl?
from an intuitive standpoint, i would have to say yes: the exertion of the current corresponding to the peak voltage in a particular output for a longer period of time than in a non-square wave would suggest that more energy is imparted to cone motion to be radiated than for a non square wave. does this energy contribute directly to a particular SPL reading at a particular frequency? because the speaker cone moves in a continuous all the way out to all the way in motion, in a true square wave i would say little energy is actually transduced into audible higher frequency components, and probably contributes to the fundamental SPL reading.
ShadowStar
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It's all about knowledge, love and respect. Posts: 2579 | From: Somewhere In the Northeast | Registered: May 1999
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