User`s manual

User's manual System Amplifier K&F TOPAS
KLING & FREITAG GMBH © 2014 Version 3.1 Page 63 of 65
Butterworth
7th ord.
42 dB/
oct.
4 2.247 0.802 0.555 0.707
1st
order
Butterworth
8th ord.
48 dB/
oct.
4 2.563 0.9 0.601 0.51
Linkwitz-
Riley
8th ord.
48 dB/
oct.
4 1.307 1.307 0.541 0.541
11.1.6 AP = All Pass Filter
The all pass filter is a frequency-dependent phase shifter. In doing this, it does not cause any
increase or attenuation of frequency levels.
The Q-Factor of a 2nd order filter defines the slope of the phase jump.
2
0
50
1
00
5
00
100
0
5
00
0
1
00
0
0
200
0
0
-1
80
-1
35
-
9
0
-
4
5
0
4
5
9
0
1
35
1
80
Fr
e q
u
en
c
y i
n
[
H
z]
P
h
a
s
e i
n
[
°]
Fil
t
e
rType
=
'
A
P'
(Al
l
pa
s
s
F
i
l
t
er)
Fr
e
q
= 100
0
H
z
1.Ordnung (0.707)
Q =
0
.
2
Q =
0
.
5
Q =
0
.
707 2.Ordng.
Q =
1
0
You can choose between a high pass filter 1st or 2nd order. The Q of a 1st order high pass
filter is always fixed. At a 2nd order high pass filter Q is adjustable in steps of 0.001 from 0.2
to 20.
11.1.7 Notch = Notch Filter
This filter reduces a selected frequency down to complete cut-off. Feedback and interfering
frequencies are reduced.
The Q-factor determines the slope of the filter.
The Q-factor of notch filters is usually between 0.1 and 20.
After changing the type of a filter the value of Q is set to the default value 4.318.