Zero One Ti 48 Instruction Manual page 33

Ti48 Instruction Manual v1.2
12.2 Details of the Digital Processing Options
12.2.1 Upmode
There are five digital filters available in the Ti48. They are listed in order of
increasing steepness of the filter and complexity .
Filter Comments
This setting offers the best transient performance, but the highest level
None
of out of band noise (some equipment does not handle this well,
resulting in lowered performance).
For oversampling modes (88.2, 176.4K), this setting does not employ a
filter, but repeats the samples instead to make up the appropriate
number. So 88.2, the processor outputs each CD sample twice, while at
176.4K, every four times.
For upsampling modes (48, 96, 192K), it is not feasible to output
without any filtering, so weighted line interpolation is used. This should
not be considered a filter suitable for critical listening, and is included
to keep the audio going whilst navigating through the different options.
This is a special setting for oversampling modes, which uses half­length
Purist
versions of the HQ1 filters, giving a non­linear phase response but also
no "pre­ringing" of the impulse. Upsampling modes are as per HQ1.
These filters offer gentle low pass filtering, to reduce filter ringing just
HQ1
outside what is considered to be the "audio band".
These filters are steeper than HQ1, but gentler than HQ3. That's it.
HQ2
These are the steepest filters available, approximating what is
HQ3
commonly termed a "brick wall".
12.2.2 Uprate
There are five sampling rates at which upsampling can be performed as well
as the "no upsampling" option of 44100Hz.
Sample Rate
44100Hz (44.1kHz)
48000Hz (48kHz)
88200Hz (88.2kHz)
96000Hz (96kHz)
176kI2S (176.4 kHz) only available in I
192kI2S (192kHz)
Comments
CD audio (Red Book) standard ie. no upsampling
2
S mode (see Device)
2
only available in I S mode (see Device)
33