24
Figure 11. PS1 Tone Control Range
1.9.4 Master Volume
The microcontroller polls the remote in regular intervals. The microcontroller transfers the mas-
ter volume setting to the DSP which implements them for each channel as shown in Figure 5.
The master volume should mute the system if all the way down and then ramp up to a nominal
value of 0dB at the center position. From the center position to “all the way up” the master
volume increases the gain by another 12 dB.
1.9.5 Preset Switching
The microcontroller polls the preset switches on the panel board in regular intervals and trans-
fers the values to the DSP. If the DSP detects a change in the setting, it will mute the respective
channel, load the new filter coefficients according to a lookup table, clear the filter state coeffi-
cients and un-mute the channel again. This takes about 1 to 2 seconds.
Presets are basically a spectral correction (like an EQ) to the signal. Preset “00” corresponds to
flat. An easy preset to check is 97 which is a 1 kHz band pass filter (“telephone” sound). In
addition to the spectral EQ, there is also a noise gate available.
1.9.6 Bass Line Out Detection
The microcontroller polls the normalling switch on the Bass Line Out connector in regular inter-
vals and transfers its state to the DSP. If the DSP detects a change in the state, it will mute the
entire power stand, latch in new system EQ coefficients through a lookup table, clear the system
EQ state variables and un-mute the power stand. This takes about 1 to 2 seconds.
1.9.7 Bass Module Detection
The microcontroller measures the resistance between the pins 2- and 2+ of the Amp3 Out
connector in regular intervals and transfers the setting to the DSP. If the DSP detects a big
enough change in the setting, it will mute the entire power stand, latch in new system EQ coeffi-
cients through a lookup table, clear the system EQ state variables and un-mute the power stand.
This takes about 1 to 2 seconds.
THEORY OF OPERATION
10
2
10
3
10
4
-20
-15
-10
-5
0
5
10
15
Fre quenc y (hertz)
dB
V
/V
P S1 tone controls
10
2
10
3
10
4
-20
-15
-10
-5
0
5
10
15
Fre quenc y (hertz)
dB
V
/V
P S1 tone controls
10
2
10
3
10
4
-20
-15
-10
-5
0
5
10
15
Fre quenc y (hertz)
dB
V
/V
P S1 tone controls
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 ...
