General Music eLEM TM 12.2 ACTIVE, Блок-схема

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BIAS ADJUSTMENT
Instruments, materials and tools:
- Audio Generator
- Dual Trace Oscilloscope
- Digital Voltmeter (or Multimeter)
- 4
Ω
500W and 8
Ω
100W Resistors
- Temperature Meter
Setup:
- Connect the Audio Generator to the input and set it to output at 2KHz sinusoidal signal.
- Insert the temperature sensor through the interstize between the heatsink and R93 (PTC).
- Connect the 4
Ω
500W resistor to the amplifier output instead of the woofer speaker and 8
Ω
100W instead of tweeter speaker.
- Connect the oscilloscope probes (setting 20V/div.,1ms/div.) on the loads.
- Insert the voltmeter terminals on R107.
ADJUSTMENT PROCEDURE
1) Turn on the amplifier, pressing "UP" "DOWN" and "MIDI" simultaneously, check that the display shows "C".
2) Set the input signal to 0dB (0.775Vrms).
3) When the temperature has reaches about 45°C (109°F) set the signal input to minimum (0 or -
).
4) Adjust the trimmer R111 to read a voltage of 6mV ±0.1 on the multimeter.
5) Check that the voltage across the R108 resistor has the same value.
6) At the same temperature condition, adjust the VR1 trimmer to read 2.2mV ±0.1 at R24 resistor.
7) Check that the voltage on the R25 resitor has the same value.
Veryfing:
1) Increase the input level to obtain an output voltage about of 0.5Vpp.
2) Check with the oscilloscope that the output signal is without a cross-talk distortion and eventually slightly
adjust the R111 or VR1 position until distortion disappears.
(Note: the voltage value across the R107 or R108 resistor must not exceed 10mV and the R24 or R25 resistor must
not exceed 4mV).
LIMITER ADJUSTEMENT
1) Increase the input level to 10dB, adjust the trimmer VR1 until clipping distortion disappears.
2) Verify tha the led change colour from green to red.
3) Re-connect the speakers instead of the 4
Ω
and 8
Ω
resistors.
TOUR MASTER 12.2 ACTIVE - Technical Specifications
SPEAKER SPECIFICATIONS
CO MPO NENTS High
1" driver with controlled directivity horn
Low
12" low frequency speaker
HIGH section PO WER HANDLING W continuous 50
(EIA RS-426A) W peak 150
LO W section PO WER HANDLING
W continuous 300
(EIA RS-426A) W peak 900
IMPEDANCE High
ohm 8
Low
(nominal) 4
CO NSTRUCTIO N Cabinet: bitch plywood
Finish: Black scratch-resistant paint
Protection grille:metal grille
WEIGHT kg - lbs. 32 - 70,4
DIMENSIO NS mm - in. 400x610x396 - 157,5x240,2x156 (WxHxD)
PROCESSOR SPECIFICATIONS
INPUT Se nsitivity
dB 0
Impedance Kohm 30 (balanced) - 15 (unbalanced)
A/D conve rter bit 18
D/A conve rter
bit 18
Dynamic range dB 105
Sampling rate
kHz 48
CRO SSO VER Fre que ncy
Hz 1800
Slope dB/oct. 24
HIGH section PO WER AMPLIFIER W continuous 100
LO W section PO WER AMPLIFIER
W continuous 300
AMPLIFIERS DISTO RTIO N T HD + Noise <0,02%
CO NTRO LS VOLUME control
UP & DOWN selector buttons
MIDI button
Earth Lift
DISPLAY 2-digit display
SIGN/COMP LED
CO NNECTO RS 1 XLR-F + XLR-M (input + link)
MIDI IN & MIDI T HRU
PO WER SUPPLY
see label on the apparatus
SYSTEM SPECIFICATIONS
FREQ UENCY RESPO NSE Hz 60÷20000 (-10dB)
SENSITIVITY MAX SPL SPL 1W/1m
dB 98
continuous 124
DISPERSIO N ANGLE orizontal ° 80 (±5)
vertical 50 (±10)
DIRECTIVITY Factor (Q )
dB 7
DIRECTIVITY Index Di 8,5 (+3,7, -2,3)