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Manual UC1 © Grimm Audio
17
The large number in the display indicates the current
monitor gain level in dB’s. The monitor outputs offer 8
dB of clean gain above ‘0’ on the display. In other words:
a full scale signal will only reach full scale on a monitor
output if the monitor gain is set to +8 dB. This may
seem odd, but the idea is that the ‘0’ indication of the
display is your reference playback level to which you
always return after a louder of softer playback. This is
common practice in mastering. The ‘0’ level is usually
aligned with an SPL of 79dBC when playing a SMPTE
reference noise signal on a single channel. The Grimm
LS1 is factory aligned to that, you may adust the gain of
your 3rd party amplifier to achieve the same result - or
to select another acoustic SPL that suits you as
reference playback level.
Note that the monitor gain can be set to display values
up to +18, which means that there is 10 dB of positive
gain available in the UC1 to audition very soft noises.
Note that any signal above -10 dBFS will in that case clip
– please use this extra gain with caution!
The volume control is in 0.5 dB steps above -17 dB and
1 dB below it. If you have a Grimm Audio LS1 or PMC
digitally controlled loudspeaker connected to the
proprietary cat 5 output on the back, the volume control
takes place in the DSP of the loudspeaker. In all other
cases the volume control is in the DSP of the UC1. At
volume setting ‘+8’ the data to the digital output and
build-in DACs is put through transparently. At other
levels the digital gain control is properly dithered at 24
bits. Optionally, volume control of the main out can be
disabled in the menu. In that case the indicated monitor
gain only applies to the 2nd out and phones.
Main screen, Digital 1/2 selected, in phones mode
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