1. DESCRIPTION
Recording Characteristics.
Pick-ups
should
be tested
with
reference
to
the
internationally
recognized
characteristics
if
th
ey
are
int
en
ded
to
give co
nstant
output
as
a
function
of
frequ
ency. Gliding
frequency
records
s
hould
in
general
be
cut
according
to
the
recording
character
istics
shown
in
Fig.
1.10-bottom
.
In
the
case
of
the
B & K Gliding
Frequency
Records
, a
charact
e
ristic
as
shown
on
top
of
Fig. 1.10,
which
is
converted
by
an
e
qualizing
filter
in
th
e
measuring
chain
to
th
e
appropriate
characteristics
has
been
adopted.
The
reaso
n
for
the
high
fre-
quency
level
limitation
on
the
record
is
that
if
tru
e
reproduction
is
intended,
th
e
radius
of
curvature
of
the
modulated
groove
wall
must
re
main
apprec
ia
bly
larger
than
th
e
stylus
tip
radius
.
The
wave-length
be
ing
de
termined
by
the
chosen
groove
speed,
and
th
e
stylus
tip
radius
being
norm
alized
to
15-
18
fl
for
stereophonic
pick-ups
,
this
sets a
db
IIII
I I I I II
HttIT
11
11
1
::
0
"g
~
/ Recording Characteristic
0
".....
Gliding Frequency Records
ClR
2007 &
ClR
2009
II
IIII
I I I I II
IIII
I
r
: -20
20
f.- 50
100
200
500
1000
2000
10000 20000
20
r--
Type
1,409
Equilizing Filters Characteristics /
db IN
Filter
Switch pas: I.E
.C.
Curve 2, "
10
..
"
":I.E.C
. Curve 3
II
I I
r>-
Filter StitCh
pas.:
Lin.
.1:-::=':'
-
0 II
III
I I
~
~
_~
50
100
200 500
1000
2000 10000 20000
+:::
::
:1
:1:111
:1
::
=::1
:
:::::=::
:
::=::
TotaL
Characteristics I
-
(TfiS
,
f~12001/19+4t09I
H++t
+-+-f-
H+Ht
w
,,"-llri
+10
f-
H--f-jf++
++-
+
+-
+-+++++++--++-++
w!+.l1If-H
Fi
lter Switch pas. :
lin
.
~
O
f----
H+H+++-++-~
I
~\++~~~~--++~~_+H
~
.
~
_10f----
H +
H+
tl-+9-V
-t-+
-tFilter
.
SwitchP05
.:
I.E.G.
curve~
J
/'
I
..
II "I I " :
1.~
.
Ci
~
u
ll
e
l
~
-20
t==T-+-t-ttttl
I--t--t--++-t-t+lttt-III
I
-++-+-++
I
H+
11
1tt--H
II
III
I I
IIII
I
20
50
100
200 500 1000 2000 10000 20000
{.6
Z32~
Fig. 1.10. Recording characteristics available
when
using
the
Gliding Frequency
Recordings
in
connection
with
the
Response
Test
Unit
Type
4409.
The
curve
no. 3 is specified
by
the
International Electrotechnical
Commission
in its
publication
no.
98-1 for steI'Cophonic recordings.
9
