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1.3.2 Implementation
The power stands detects:
a) The number of bass modules B1 connected to “Amp3 out”. This is done by measuring the
impedance between pins 2+ and 2- of the “Amp 3 out” connector. The B1 bass module has a
10k ohm resistor between those to pins.
b) The insertion of a 1/4" jack into the “Bass Line Out”. A normalling connection of this jack is
connected directly to a flag pin on the DSP.
Depending on these detections, the PS1 will change system EQ and limiter settings. This infor-
mation is collected by the DSP and determines EQ and limiter settings through a lookup table:
Table 5. EQ lookup table for all operational modes
1.3.3 Debug Mode
Debug mode is entered when a resistance of 1k ohm or less is detected between pins 2- and 2+
at the “Amp3 Out” connector. In debug mode, all system EQ’s are set to “flat” and the internal
limiters are bypassed. Most measurements should be done in debug mode.
A simple way to switch between the different modes is to create a “dummy” cable that brings out
pins 2- and 2+ to a banana plug. The modes can be switched by applying different numbers of
10k ohm resistors or a short between the leads of the banana plug. Pins 1+ and 1- of the
“dummy” cable can still be routed to a Speakon
®
connector to attach B1 bass modules.
THEORY OF OPERATION
Number
of Bass
Modules
Impedance,
Amp3
2+ - 2-
Bass
Send
connected
Bass
EQ
LA
EQ
Comment
0
infinity
No
0
0
No bass module:
L1: Select highpass at 110Hz
B1: 40-110Hz flat bandpass
1
10k ohm
No
1
1
L1: crossover at 180 Hz
B1: “nominal EQ” +6 dB
2
5k ohm
No
2
1
L1: crossover at 180 Hz
B1: “nominal EQ”
0
Infinity
Yes
3
2
This mode is for use with external
powered sub.
L1: crossover at 180 Hz
B1: flat 40Hz to 180Hz
1
10k ohm
Yes
4
1
Undefined state, user may be using
an external 3
rd
party device with a
single B1
L1: crossover at 180 Hz
B1: “nominal EQ”
2
5k ohm
Yes
5
1
This is the nominal case with an
additional external power stand
connected
L1: crossover at 180 Hz
B1: “nominal EQ” -6 dB
??
0
Either
6
0
Debug Mode: all EQ and limiters
are by-passed.
Содержание Personalized Amplification System
Страница 3: ...3 THEORY OF OPERATION Figure 1 PS1 signal flow Diagram ...
Страница 44: ...44 APPENDIX CS5361 AD Converter Pinout and Table ...
Страница 45: ...45 APPENDIX CS8406 Digital Audio Interface Transmitter ...
Страница 46: ...46 APPENDIX CS8416 Digital Audio Interface Receiver ...
Страница 47: ...47 APPENDIX TDA8929T Digital Amplifier Controller ...
Страница 48: ...48 APPENDIX TDA8927J Digital Power Amplifier ...