Logidy EPSi, Руководство пользователя

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8
4. Parameter List
4.1. Version 1.00 Parameter List
Display Meaning Values
1.Sd
The Index of the SD
Card File used as an impulse
response
The values available
depend on the contents of
the SD Card (see file
naming section)
2.FL
FX Level. The level of the
processed audio AKA “wet”
level.
Unit: dB.
Range: -40dB to +10dB
Actual resolution: 0.25dB
steps
3.rt
Reverb Time. The decay
time in seconds for the impulse
response. This is the measured
RT60
Unit: seconds
Range: from 50% to 150%
of the nominal time of the
impulse response*
4.dr
Dry Path Enable. The
state of the internal analog
direct path relay.
Unit: none
Range: on - off
* Increasing or decreasing the perceived decay is done by applying a volume
envelope to the impulse response. When increasing the decay time, the
envelope adds gain to the end of the tail also increasing whatever noise might be
in the file. This can sometimes make the tail sound unnatural.
4.2. Version 1.00 Algorithm
4.2.1. Quality
Convolution is a straightforward process. Although there are several ways this
process can be optimized for computational bandwidth, the end result can not
differ form the simple theory. At the root and with a large enough bit depth (32-bit
floating point in our case) all convolvers sound the same. The quality of the
sound generated largely depends on the quality of the impulse response used.
A peaky or fluttery impulse response form a low quality algorithmic reverb unit
will sound the same on the EPSi. However an impulse response from a very
diffused and uneven acoustic space will sound as smooth and transparent on the
EPSi.