BRUEL & KJAER 4409 User guide

Response Test Unit Type 4409
Test Records Types QR 2007-08-09
The test unit and r ecordings have been designed
to aid the accurate investigat i ons of the frequency
re sponse of sound reproducing equipment i.e.
record ~Iayersl tape & film recorders etc.
BRUEL & KJ.N..H
N",rum, Denmark. I!E 800500 . .;:>" BRUKJA, Cop enhagen. Telex: 5316
Be 440Q

Response Test Unit
Type 4409
Test Records
Types OR 2007 -~09
FEBRUARY 1964

Contents
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3
Purpose of the Equ ipm ent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3
Description of the Test Records ... . ... ..... . ............. . ......... 4
General. . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4
Recording Characteristics ........... ... ...... .. . .. . . .. . .. . . . ..... .. 9
Recorded Level Tolerances ............. . .. ..... . ..... . .. ......... . 11
Response Test Unit Type 4409 .. ...... .... .... . ...... .. . ...... .... .. 13
Channel Selector ....... ........... .... ....... .... ...... .. ....... . . 14
Equalizing Filter ........ .... . .. .................... . .. . ........... 14
Synchro -Starter ............... .. ......... .. ... . .. .. .. . ............ 14
General Description ...... .... . .. . .... .. . . .................. . ....... 14
Functioning . ...... ... . . . .. ..... ................................... 16
2. Operation ................ ...... .. . ................ . ... .. ......... 17
Practical Hints for Use of the Test-Records ..... . . .. . .. ... ...... ... .. 17
Aut omatic Frequency Response Plotting ... . ... . ..... .. . ...... . . .... 17
Automatic Gliding Frequency Cross-Ta lk Measurements . ............. 19
General . .......................................................... 19
Operating Procedure ........ . ... . . .... .. . ...................... ... 20
Synchronous Filtering Adjustment . ... ... ... .. ... . . ........ . .... . .. . 22
Automatic Distortion Measurements ............. .. ........ . ........ 25
Examples of Practical Results ..... ... .... . ...... . .. .. . . . ... ... . .... 26
Use of th e Te st Record QR 2008 . ..... .. .... ..... . .... .. ......... . .. 28
Spot Frequencies ... .... ..... .. . ......... .......... ................ 28
1 Kc/s Reference Tones . .... .. . .................................... 28
100 C/S Tracking Test ................ . ..... . .. .. ..... . .. ...... . .... 28
Tone Arm Resonance ..... . ... .. .. ...... .... . ... . ... ... ..... .. ..... 29
Test of Tape Recorders etc. .... ... ......... . .... .. . .. . ........ . .. .. 30
Synchro-Start of a Continuous Recording ... ........ .. .. . ............ 33
Specifications . ............ .... . ...... . ..... . ............ ........... .. 34

1. DESCRIPTION
1. Description
Purpose of the Equipment.
Th e Response Test U nit Type 4409 is int ended for use with the B & K a ut o-
ma ti c fre qu en cy res pon se plotting e quipm e nt wh en investigating th e fre qu ency
r
espo nse of so un d re pr o du cing e quipm ent.
Fi
g. 1. 1 shows an example in whi ch the 44 09 a nd a test record are in vol ve d in
th e testing of a stereo ph onic record player.
Le vel recor de r
Fi g. 1.1. Meas uring se t-up for a ut om a ti c plo ttin g of th e frequen cy r espo nse
of a stereopilOnic reco
rd play er.
The 4409 fulfils thr ee differe nt fun ct io ns:
(a) cha
nn el sel ec ti on in th e case of stereo ph onic equipme nt either man ually,
wh en o nl y one cha nn el is inves ti gat ed , or a ut omatically at a recur ing fr e-
quen cy of 1. 2 cis for a ut omatic cross-ta lk or co mp arison meas ur eme nt s.
(b) e qnali zation, by differe nt RC filters, of th e recording cha r acter istic of the
test
reco rd.
(c) sync hr onization of th e pape r-driv e of th e Level Recorder Type 23 05 with
th e reference r ec ord ings (reco rd or tap e) und er re pr o du ct ion.
It is thu s possible to a ut omatically pl ot th e frequency response of the sound
re produ cing eq uipm ent. A typical expe rim e nt al result is shown in Fi g. 1.2.

1. DESCRI PT ION
Wh ere th e recorder is int egrated with th e re produc er, as in th e case of tap e
reco
rd er s, motion pictur e systems etc., refere nc e reco rdin gs are taken from
th e consta nt voltage output of a generator, but in the cas e of phonogr a ph
testing, accurate refere nc e disc r ec ordin gs are ne eded.
The Gliding Frequency Reco rdin gs Type QR 2007 a nd 2009 are especially
designed
for th e purpo se of fr e qu e nc y res pons e investiga tion . They provide
OOODOODaOODDOOOODOOO OOO OOODODOO aOOOQOO OOOOoooooooo
"':!!'.' ." ~ ............ ......,..... ..... . ..... 1(1 :IS
........ - -- ..
StereophoniC
piCk. up type «I Z
Ortof on SPII.G
No 1
Fil ter l in"
OR 2007 Mod1
~ ----
~~- -- .,
LUoo.r., __ _
,... lOdS
::..s,.,~ .
~f_s.. ... ,- O OIO
QP 1123 10
Fi g. 1.2. Typical ex perimental result obtained by means of ti le se t-up of Fig.
1.1.
(Test of a high qllality stereophonic head pr esenting a certain unbalance).
The total duration of one plot is 35 sec. between th e instant wh en the pick-up
is put d ow n on th e record QR 2007 and th e ins tant wh en th e set-up is r ea dy
to start a new plot.
co ntinuou s frequency sweeps fr om 20 cis to 20 kc l s, with late ral mod ul a ti on
on
the QR 2007 and left, rig ht , late ral , ve rtical modul ations on th e QR 2009.
The Pickup Test Reco rd Typ e QR 2008 i s, on th e ot her ha nd , designed for
meas ur eme nt s at fixed frequencies and for ton e a rm res on ance investigation s.
It is int e nd ed for pick-Up design work , and also for general purpo se chec ks in
com bin a ti on with the gliding fr e qu e ncy reco rds wh en c ur ve plotting e quipm e nt
is not ava ilable.
Description of the Tcst Records.
General.
The B & K referenc e recordings are delivered in box es containing five ide ntical
vinylite reco rds and one instruction manu al (Fig. 1.3).
Both sides of eac h record being id en tical, a total of ten sides are ava ilabl e,
a large enough qu a ntit y to g uar a nt ee a great numb er of pl ay ings without
4

1. DESCRIPTION
alteration of the characteristics. This number, however, is greatly dependent
on th e care exercised in th e use of the records. By conserving one side as a
reference, it is possible to
check on th e service lif e of each record in use.
Fig. 1.3. Gliding Frequency Recordings Type QR 2007.
The cutting process and th e dimensions are in accordance with the Recor.:-
me
ndation of th e Int erna tional Electrotechnical Commission ( lEC 98/98-1)
recogniz
ed by most countries.
The detailed specifications are given at the end of this manual.
The reproduction of th e label of the QR 2007 (Fig. 1.4) and the photograpb
of a section of th e record, illuminat ed by a grazing light beam (Fig. 1.5),
s
how th e exact composition of the recordings .
The QR 2008 a nd QR 2009 are desc rib ed in the same way by figures 1.6
through 1.9.
The original sinusoidal signal used for recording th e disc tracks was obtained
from a B & K B eat Frequency Oscillator with especially low distortion. For the
r ecor din g of th e gliding frequency bands the frequ e ncy of the signal was vari ed
according to a fun ction of time which was purely logarithmic within± 2.2 %
± 1.3 cis.
This tolerance is e qual to th e tolerance on the de termination of the recorded
frequency when using the Gliding Frequ e ncy Records at th e exact specified
rot a tion speed (45 rpm ) and assuming a logarithmic sweep.
5

1. DESCRIPTION
All rights res erv8a
Briiel & Kjan
Copenhage n Denmark
Monophonic
Gliding Frequency Record
20-20000 cIs
Type OR 2007
o
45 r.p.m. 6
Frequency Sweeps: logarithmic 20 cIs to 20 kc/s in 15 seco nds
Start Marking (20 cIs point): Cease of the 1 kc/s si gnal preceeding each ba nd
Recording Characteristic: lE e Standard No.3 without treble emphasis
(constant velocity above 1 kcfs) .
Recorded Velocity at 1 kc /s: 3.16 em!s r. m.s.
Bands 1 to 10: lateral cut
/63695
Fi g. 1.4. La bel of th e QR 2007.
10
QR 2007
Bands 1 to 10 : A B
20 cis 20 kc /s
8/9 octave per re v.
Fi g. 1. 5. Section of tile QR 2 00 7 sh ow ing tile succession of glidin g fre qu ency
ba
nd s pr eceded by a 1 kc/s sta rt a nd reference signal.

AU r igh ts reserved
Briiel & Kjmr
Copenhagen Denmark
Pick-up Test Record
Section 1
ve r~~i~~ 1~: e ,~~~~j~~ ~s~Oc ~ . ~~s~ i~2:i5 ~ ~~d k ul~t io n .
Sand 1: 45 ° l eft modulation (A). Sand 2: 45 ° right modulation (B).
Section 2 0 Section 3
Reference Tones, 1 kcls, 4 x 60 sec . ' Lateral Tracking Test,
Velocity level : 2.24 cm/ sec. rm s (45 0) 100 cIs (A+ B), 5 x 15 sec .
(3 . 16 cmls lateral or vertical) Sand 1: 0. 00 1 cm peak amplitude
::~~ ~ ~ :~~ ~ ff~t ( ~~) ::~~ ~~ g : ~ : " ..
Sand 3: l atera~ (A+B) Sand 4: 0.004 ..
Sand 4: vertical (A-B) SlInd 5: 0.005 ..
Sect ion 4
Vertical Tracking Test , as section 3 but wi th vertical (A- B) modulation.
Section 5
Logarithmic Frequency
Sweep s 10 cIs -100 cIs in 161 /J sec .
Start Marking (10 cIs point): cessation of the 1 kcls sig nal
R
ecorded lever~~~~~~~t ~~~ l i~~d~·0.OO 113 em peak.
Sand 1: 45° left (A) Sand 3: lateral (A+ B)
Sand 2: 45° right (B) Sand 4: vertical (A - B)
Sect ion 6
as se ction 1, but wit h sma ll groove spe ed
~.cord . ",.~\ (63696
tJd on ORTO FON e.o.U \~
Fig. 1. 6. Label 0/ th e QR 20 0 8.
5sot freguencies
2 -16-12.5-10 kc/s
(0 .6 cm/sec rms)
·1kc/s reference
tone
(3.16 cm/secl
(compliance) A+B
Tracking test 1
100 CIS bands of
increasing amp!. A ~ B
0. 001 to 0.005 cm
10-100 cIS SWl!ePS } A
constant amplitud B
(0.00113 cm peak) A+B
for tone arm A-8
reSonance
as first section } ~
QR 2008
2
3
4
5
6
(33h rpm)
+61~2
1. DESCRIPTION
Fig. 1.7. Section 0/ th e QR 2008 sh ow ing the succession 0/ bands.
7

1. DESCRIPTION
. ~::- ~
/ ~ ."
I Briiel &
Kjcer
Copenhagen Denmark
Stereophonic
Gliding Frequency Record
20-20000 cis
Type OR 2009
o
45 r.p.m. ,6.
Frequency Sweeps: Logarithmic 20 cIs to 20 k c/s in 50 secon ds
Start Marking (20 cIs p oi nt ): Cease of the 1 kc/s signal preceeding each band
Recording Characteristic: IEC Standard N o.3 without treble emphasis
(constant vel ocity above 1 kc/s)
Recorded Velocily.t 1 kc /s: 2.24 em!s r. rn .s. in 45 ° modulation
(3.16
em /s in lateral and vertica l m odulat ions)
Bands 1 and 5: 45 ° left m odulatio n (A)
Bands 2 and 6: 45 ° right modulation (9 )
Bands 3 and 7: lateral modulation (A+ B)
Bands 4 and 8: vertica l modulation (A - B)
Fig. 1. B. Label of th e QR 2009.
A
-V-
S
~
AtS
~
A
S
A+S
A-S
Fig. 1.9. Section of the QR 2009 showing the succession of gliding frequen cy
bands preceded by a 1 kc/s start and reference signal.
8

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