Quote:
Originally Posted by digitaltoast
During install, it wants to install to folder 4.11 and won't let me change path.
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That's because the installer will "upgrade" the existing installation - which is located wherever you originally installed LameXP.
Quote:
Originally Posted by digitaltoast
When encoding mp3, even when I override the samplerate and enforce 44.1KHz, it downgrades to 32KHz etc, at anything above VBR compression level 6.
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And that's because of LAME's psycho-acoustic model.
The
sampling rate determines the highest frequency that can be retained (cf.
Nyquist–Shannon sampling theorem). So, by reducing the sampling rate from 44.1 kHz to 32 kHz, you are effectively
low-pass filtering the audio. In other words, the highest frequencies are discarded
before the actual encoding. At a sampling frequency of 44.1 kHz the highest audio frequency that can be retained (without aliasing) is 22.05 kHz; at a sampling frequency of 32 kHz, the highest audio frequency that can be retained is 16 kHz. Low-pass filtering the audio makes a lot of sense at very
low bitrates (or the
lowest VBR quality levels), because loosing the highest frequencies is way
less disturbing than the compression artifacts that arise otherwise.
Note: It's possible to "force" LAME to encode at the original sampling rate, by explicitly specifying the "--resample" option with the
original sampling rate. But you almost always do
not want this!