Transcript Articula

Active Speakers and Amplifiers
COMPONENTS
 Amplifiers
 Active Crossover
 Control Circuits
R. R. Cordell 10/18/03
Active Speakers and Amplifiers
Most people own an active speaker system
 Subwoofer
 Computer Speakers
R. R. Cordell 10/18/03
Active Speakers and Amplifiers
ADVANTAGES
 Too many to list
 Dynamic range, peak power
 Efficiency
 Small, inexpensive XO components
 Greater control of driver dynamics
 No speaker cables
 Absence of XO interactions
R. R. Cordell 10/18/03
Active Speakers and Amplifiers
The Gain Clone
+35V
+
IN
100K
LM3886
-
~ 60W @ 8 ohms
OUT
-35V
20K
1K
220
1 uF
3.3
+
IN
1M
100K
LM3886
220 pF
-
0.047
20K
1K
50 uF
+
OUT
3 uH
3 Hz
R. R. Cordell 10/18/03
22
Active Speakers and Amplifiers
INVERTING GAIN CLONE WITH SMALL CAPS
1M
6 Hz
+
1 uF
0.1 uF
+
1.6 Hz
+
IN
1M
1M
OPA2604B
10K
-
LM3886
1K
BUFFER
OPA2604A
INVERTER
-
10K
R. R. Cordell 10/18/03
20K
OUT
Active Speakers and Amplifiers
INVERTING SUPER GAIN CLONE
+
+
+
IN
1M
INVERTER
LM3886
1K
BUFFER
-
OPA2604B
10K
-
OPA2604A
10K
-
20K
0.1 uF
1M
0.3 Hz
INTEGRATOR
1M
LF356
DC SERVO FEEDBACK
+
OUT
Active Speakers and Amplifiers
NON-INVERTING SUPER GAIN CLONE
+
IN
22K
LM3886
100K
-
DC SERVO FEEDBACK
10K
INVERTER
1K
0.3 Hz
10K
-
LF353B
+
20K
0.1 uF
INTEGRATOR
1M
LF353A
+
OUT
Active Speakers and Amplifiers
ACTIVE CROSSOVER
IN
BSC
LPF
750 Hz
NOTCH
4 kHz
LINKWITZ
TRANS
HPF
750 Hz
LPF
4 kHz
NOTCH
9 kHz
MIDRANGE
EQ
LF
MF
HPF
4 kHz
HF
Active Speakers and Amplifiers
Voltage Follower Filters
IN
+
OPA604
OUT
BUF
-
2 kHz First-Order LPF
7.95K
0.01 uF
+
-
Fourth-Order L-R LPF
+
+
-
-
Active Speakers and Amplifiers
Voltage Follower Filters
NOTCH FILTER
IN
+
OUT
-
+
-
Active Speakers and Amplifiers
ACTIVE BAFFLE STEP COMPENSATION
IN
+
OUT
100 pF
10K
10K
0.01 uF
Active Speakers and Amplifiers
Linkwitz Transform
R2
R2
C2
R3
C2
R3
C3
R1
R1
IN
OUT
+
47 Hz, 0.56 -> 20 Hz, 0.6
R1 = 14K
C1 = 1.0 uF
R2 = 79K
C2 = 0.056 uF
R3 = 79K
C3 = 0.18 uF
Active Speakers and Amplifiers
Active Speakers and Amplifiers
Active Speakers and Amplifiers