User’s Manual
K&F Self Powered Subwoofer Systems ‘SP’
KLING & FREITAG GMBH ©2003 - 2014
Version 7.0, 09.09.2014
Page 22 of 48
8.2
Operations with K&F System Controller
For optimal performance with an extended functional range we recommend using a
K&F system controller. Instructions for use, connecting diagrams and detailed descrip-
tions of the latest
controller models ‘CD 24’ and ‘CD 44’ you can find in the correspond-
ing user’s manuals.
8.3
Maximum Configuration
It is possible to use a large number of SP speakers in parallel simultaneously, however
this number is limited according to the permitted minimum load impedance of the sig-
nal source (e.g. mixer, equalizer, etc.).
The total input impedance of all SP speakers must be larger than the permitted mini-
mum load impedance of the signal source. If no manufacturer’s recommendations can
be found, take the output impedance of the signal source. In this case we recommend a
total input impedance at least 10 times higher than the stated output impedance of the
signal source.
(The output impedance of your signal source can normally be found under Technical
Specifications in the manufacturer’s instruction manual).
Definition:
source
signal
of
impedance
output
R
OUT
=
50.000
Ω
50k
Ω
speaker
-
SP
impedance
input
R
IN
=
=
=
speakers
SP
of
number
d
recommende
maximum
n
MAX
=
The maximum number of SP speakers can be calculated with this formula:
10
50
10
n
MAX.
×
Ω
=
×
<
OUT
OUT
IN
R
k
R
R
Example:
Ω
=
75
OUT
R
10
75
000
.
50
10
n
MAX.
x
R
R
OUT
IN
Ω
Ω
=
×
<
66
n
MAX.
<
⇒
Important
