Here's where you make the settings concerning the playback and processing
of the music.
Sample rate:
The highest frequency a digital audio recording can reproduce is half
the sampling frequency. This means that a higher setting will increase
the audio quality but will also increase the time taken to process it.
A CD is always recorded with a sampling frequency of 44100 Hz, MP3/AIFF
files may have been recorded with any sampling frequency.
You may here choose to lower the playback frequency and thus decrease
the processor work by selecting the 22050 Hz or 11025 Hz items.
The 44100 Hz item leaves the sample frequency of a CD unaffected but may
lower it for an MP3/AIFF file.
The "No change" item does not at all change the sample frequency.
Note: Audio files with a lower sampling frequency will not be "upsampled"
to the given setting.
Pre-filter
When using a sample frequency setting of 11025 or 22050, you may need
to filter out some of the higher frequencies. If higher pitched sounds,
such as a hi-hat, sound distorted, check this item. This increases the
processor work.
Slow Down Quality
The sound quality setting for the corresponding slow down type - higher
means better but uses more processing power.
Read Buffer Size
A bigger setting may work better on slow computers, a smaller setting
makes the program reacting faster for pitch and speed changes.
If you experience dropouts in the playback, try using a bigger setting.
Pitch change affects speed
Normally changing the pitch does not affect the speed or vice versa. However
there may be situations when you do want this to happen.
Say you have recorded something from a tape recorder running at a slightly
different playback speed than the original recording or if you are recording
old 78 rpm records at 45 rpm. You would then want a pitch change to affect
the speed as well. If so, enable this item. This will disable the Speed/Stretch
slider and only the Pitch slider will be active.
To find out how to set the Pitch slider, either use your ears and adjust
it until you are satisfied or pick up your home calculator, take a deep
breath and read on. Here's an example:
A 78 rpm record played at 45 rpm has a speed ratio of 45/78 = 0.576923
which means that the speed and pitch is lowered by the same number. Expressed
in semitones that equals to 12*log2(0.576923) = -9.52259 semitones. So
to get the music back to the original speed and pitch, raise the Speed
slider to 9.52. Simple?
Another use of this function is to set the Pitch slider to -12. This
will slow down the music to half speed and lower the pitch one octave.
You will then get a feeling how transcribing was done before software
as Amazing Slow Downer was available. Not everything was better in the
old days.
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