1 Dec
2007
1 Dec
'07
11:18 p.m.
David Olofson wrote:
On Sunday 02 December 2007, david wrote:
[...]
My guess is they're doing the same thing that Dr Moog did with his
synthesizers - use three detuned oscillators to produce waves that are a
bit spread along the frequency range. If I visualize a pure sine wave on
an oscilliscope, I think of it as a thin line cutting through the zero
line. I visualize a Moog sine wave as three lines cutting through the
zero line, each at slightly different times because each has a slightly
different frequency. (Of course, each of them is produced by analog
electronics, each may have it's own minor variations over time as it
produces the wave, so each doesn't have the rigid precision that waves
produced by digital formulas have.
David Olofson wrote:
I recently discovered that the Yamaha PSR-740 has both a
"Sine Wave"
voice and a "Thick Sine" voice. There is a big difference between
the two, yet you can tell that they're both using sine waves. So
that's my empirical experience of what is "thicker".
I'd guess one of them is pretty close to a perfect sine whereas the
other - obviously - is not. What is
thicker?
Now, that is probably very subjective, but in general, it would be
a sound with more information in it. For example, some sounds are
improved by adding slightly detuned oscillators in large numbers.
(Well, most sounds, if you're into "organic" or analog/acoustic
feel sounds in general.) Why not record and FFT them? If you can hear a
difference in timbre,
the FFT spectrum should tell you why. If you can hit an FFT bin dead
center, you should get a single peak with a pure sine, and various
extra peaks with other waveforms.
That would be a good idea. I'll have to try that with our sound guy this
Sunday - record a bit of the "Sine Wave" voice and a bit of the "Thick
Sine" voice and see what they look like. He normally converts tracks to
MP3 to share them, but I can have him keep them as WAV files for this.
Thanks.
--
David
gnome(a)hawaii.rr.com
authenticity, honesty, community