Recording Level Adjustment; Reference Signal Level And Headroom; Level Meter; Level Adjustment - Sony PCM-1630 Operation And Maintenance Manual

7
5
:(
c
Ll
"
)
.:
1-6. RECORDING LEVEL ADJUSTMENT
1-6-1. Reference Signal Level and Headroom
Headroom means the difference between the
reference signal level and the full-scale
level. The headroom can be adjusted within
a range from 20 dB to 10 dB in 2-dB steps,
which is determined by the adjustable range
(about 12 dB) of the REC LEVEL ADJUST
controls. The adjustable range of the
headroom is widest when the reference
signal level is +4 dBs (0 dBs
=
0.775 Vrms). The maximum input level is
+24 dBs. Since the REC LEVEL ADJUST
controls do not reduce the gain, the
headroom will be less than 20 dB when the
reference signal level is above +4 dBs,
while the headroom will be more than 10 dB
when the reference signal level is less
than +4 dBs.
The reference signal levels and their
corresponding adjustable headroom ranges
are shown below.
Reference
Headroom range
sional level
-6 dBs
20 dB
-4 dBs
18 - 20 dB
-2 dBs
16 - 20 dB
0 dBs
14 - 20 dB
+2 dBs
12 - 20 dB
+4 dBs
10 - 20 dB
+6 dBs
10 - 18 dB
+8 dBs
10 - 16 dB
+10 dBs
10 - 14 dB
+12 dBs
10 - 12 dB
+14 dBs
10 dB
( 0 dBs 0.775 vrms)
1-6-2. Level Meter
The 1 evel meter indicates the full-scale
level of the AID converted signal as 0 dB.
For example, when the reference signal
level is +4 dBs and the headroom is 20 dB,
the level meter reads "-20 dB" for an input
signal of +4 dBs, and "0 dB" for an input
signal of +24 dBs.
1-6-3. Level Adjustment
While observing the level meter, adjust the
signal level as follows. Be sure to set
the PEAK indication mode selector to AUTO
when adjusting the level.
1 Set the headroom with the REF MARKER
selector. The LED of the REF MARKERs
corresponding to the selected headroom
will light up. For example, to set the
headroom to 16 dB, set the REF MARKER
selector to "16". The REF MARKER LED of
-16 dB will illuminate.
Note that the REF MARKER selector setting
has no effect upon the gain, but only
changes the REF MARKER indication.
2 Input a reference signal to the unit, and
adjust the REC LEVEL ADJUST controls so
that the level meter indicators
corresponding to the selected REF MARKER
LED 1 ight up.
3 Set the SCALE selector to FINE, and
precisely adjust the REC LEVEL ADJUST
controls.
The level meter calibration changes to
display in 0.2-dB steps above and below
the illuminated REF MARKER LED. Only one
LED for each channel on the level meter
lights up. Adjust the REC LEVEL ADJUST
controls so that the level meter matches
the illuminated REF MARKER s level.
4 Set the SCALE selector to NORMAL.
1-18 (E)