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MONO MODE
This feature sums the left and right channels on
every set of outputs. This can be quite useful for
checking for phase and balance issues in mixing and
mastering. To activate mono mode:
• Push and hold the rotary encoder to enter the setup
menu. Then rotate the encoder until you reach the
mono mode screen, as indicated by the
[ ] symbol.
• Push and release the encoder to activate mono, which
will be indicated by the illuminated decimal points [.].
• Once you have activated (or deactivated) mono mode,
either rotate the encoder to advance to the next setup
menu item, or push and hold the encoder to exit the
setup menu.
S-LOCK™ ENABLE
In certain cases, the incoming sample rate of a AES3,
S/PDIF or TOSLINK input signal may be on the thresh-
old of the s-Lock lock range. In this scenario, the unit
may go in and out of s-Lock. The s-Lock Enable fea-
ture allows the s-Lock PLL to be turned off for these
situations. To enable or disable the s-Lock PLL:
• Push and hold the rotary encoder to enter the setup
menu. Then rotate the encoder until you reach the
s-Lock Disable screen, as indicated by the sL symbol.
• Push and release the encoder to toggle the s-Lock
enable status. Illuminated decimal points in the s.L.
Symbol indicates that the s-Lock, PLL is enabled. When
the decimal points are extinguished, the s-Lock PLL is
disabled.
• Once you have activated (or deactivated) the s-Lock
PLL, either rotate the encoder to advance to the next
setup menu item, or push and hold the encoder to exit
the setup menu.
FILTER PCM - DIGITAL FILTER RESPONSE
The m920 provides the user with the ability to
change the response of the digital filter used by the
DAC when monitoring PCM sources.
Fast is the classic linear phase brick-wall filter. It has
a steep roll-off to prevent any high frequency signals
from causing aliasing artifacts. It also causes a con-
siderable amount of pre-ringing and post-ringing
at the Nyquist frequency when passing transient
information. This filter is great for looking at con-
verter performance on a test bench where it might
be subject to artificially high amplitude signals near
20kHz.
Slow is also a linear phase filter but with a much
slower roll off. This filter has much less ringing and
overshoot on transient material but can cause alias-
ing distortion when presented with high amplitude
high frequency material. The idea here is that in real
music there is very little energy in the high frequency
area of the spectrum so aliasing distortion will be
negligible. This filter is more musical than the Fast
filter.
Minimum Phase has a similar roll-off characteristic
to the Fast filter but it moves all of the overshoot and
ringing so that it occurs after a transient. There is
no pre-ringing but it is at the expense of not being
linear phase. It is potentially better sounding be-
cause of this fact. However, the mechanisms for why
it sounds better are not yet clearly understood.
To set the PCM filter setting:
• Push and hold the rotary encoder to enter the setup
menu. Then rotate the encoder until you reach the
Filter PCM screen as indicated by the FP symbol.
• Push and release the encoder to enter the PCM filter
readout.
• Rotate the encoder clockwise to select the fast rolloff
response indicated by F.
• Rotate the encoder counter-clockwise to select the slow
rolloff response indicated by S.
• Rotate the encoder counter-clockwise to select the
minimum phase rolloff response indicated by P.
• Once you have set the desired PCM filter response, push
and release the encoder to store the setting and return
to the setup menu, or push and hold the encoder to exit
the setup menu.
