Table of Contents
Advertisement
2. OPERATION
position corresponding to the unmodulated channel of the band to be played
(e.g.
on Right for band 1). The Filter Selector of the 2112 (1612) should be
set to 20 Hz before starting the automatic recording. The reference signal will
not appear on the plotting since the
2112·
(1612) is normally not equipped
with a 20 Hz filter (first filter is the 25 Hz filter).
ui
E
L:
.!!!
E
0
M
ai
L
CD
"'0
-20r------------,-----------,------------~
-30
~~
~
----------~------------~------------~
\"·.....::
-40
-50
20
\~
\.Y·.
OR 2009
\{09(;.:
\Q~ ~.----~------------~--------------~
'~
...
' 1 13
octave background noise
without
'
' '
200
2000
20000
c/s
+'62368
Fig. 2.3. Third-octave analysis of disc recording noise in typical cases.
Full line: electrodynamic pick-up. Dotted line: piezo-electric pick-up.
N.B. Lower noise levels may be observed with pick-ups presenting too great
stylus mass and tip radius.
"
caaaaaaaaaccc~caccacaocaa
acccaaccca
aaaaaaca
I
1
10
,00
-
-
,;K,
-
Fr~ency-----
f6m>
Fig. 2.4. The series of third-octave filters of the Spectrometer Type 2112 or
Filter Set Type 1612.
21
Advertisement
Table of Contents
