| Odesílatel: David Balazic <[EMAIL PROTECTED]>
|
| Hmm, IIRC there is a effect called "enhancer" that adds high
| frequencies to sound that lacks them. I think it was used
| for tapes ( or something else that lacks high frequencies ).
|
| The basic idea is to find the basic tones and add higher harmonics.
|
| One way to do it is to filter out all harmonics , then over-amplify
| the signal, so that it clipps and generates a lot of harmonics and
| then mix that back into the original sound.
|
| This is done complete in analog world , so it can be applied to
| almost any type of audio material.
Sure, you are true.
But you must apply filter-out lower frequencies than base freq. If most
common base freq for exciter is 3200-3600 Hz, lower freq are filtered-out.
Then this band (3200 up) is feed into compressor engine, and you now make
even and odd harmonics by non-symmetrical clipping.
You can drive compressor, processed value and dry signal (and base freq
too).
I dont know nothink about noise modulation techniques, all highs
enhancement are done by non-linear distortion of spectrum part.
I have some demo of winamp plugin from DFX, that uses not only exciter, it
uses stereo widener, HRTF filter for 3D stereo, and compressor. lower
bitrates MP3 sounds really better, but not your own, only from internet
(encoded by xing or blade at 128k).
Regards
Jaroslav Lukesh
--------------------------------------------------
note: (Bill) Gates to Hell!
| >
| > My guess is that they take the mp3, decode it, and then
| > add noise to the spectrum above 16khz. The level of the
| > noise is taken from interpolating (actually, extrapolating
| > in this case) the data below 16khz. (is that what you
| > mean by an audio exciter?)
| >
| > Sounds like snake oil to me. But maybe adding some low
| > level noise actually sounds better than having silence
| > above 16khz?
Not sound better, but if you hear something about exclusive or luxury noise
or something that, this small amount of constant noise is applied in
communication devices such as mobile phones instead silence in pauses.
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