Sub Woofer circuit diagram - 35 Watts - TDA 7265

35Watts sub-woofer schematic using IC TDA7265

Sanyo J2503 Stereo Amplifier (Europe) - Circuit Diagram

D613E – B633E => Output Pair

25 watts x 2

AC220V, 50Hz.

Power consumption: 120W

Schematic

Infinity Bu-1 (CMS-1) – Powered sub-woofer – schematic - testing

Specifications
Dimensions
Inches . . . . . . . . . . . . . . . . 11½ x 11½ x 11½"
Metric . . . . . . . . . . . . . . . . 29.2 x 29.2 x 29.2cm plus 1¼" (32mm) for feet.
Driver . . . . . . . . . . . . . . . . 8" Woofer
Nominal Impedance . . . . . . . . . . . . 4 
Enclosure Design. . . . . . . . . . . . . Tuned Port
Amplifier Power . . . . . . . . . . . . . 50 watts RMS
Frequency Response . . . . . . . . . . . 45Hz - 150Hz (± 3dB)
Crossover Frequency . . . . . . . . . . . 50 to 150 Hz Continuously Variable

1. Auto Power - This Auto On/Off switch controls whether the BU1’s Automatic turn-on circuit is active. When the switch is ON , the BU1 will turn itself on, indicated by a green LED, when it is plugged in and receiving a signal. When the BU1 has not received a signal for approximately ten minutes, the unit will revert to the STANDBY mode, indicated by a red LED. When this switch is OFF, the unit will revert to the STANDBY mode and will stay OFF, regardless of input signal. THIS IS NOT A TRUE AC POWER SWITCH AS IT DOES NOT DISCONNECT THE AMPLIFIER FROM THE 120VAC LINE.
2. High Level Inputs - These High Level Inputs are for receivers that do not have line-level “pre-amp out” or “subwoofer out” jacks. When a pair of main or satellite speakers are attached to the OUTPUT terminals, they are driven the full range of frequencies as generated by the music source (receiver, amplifier, etc.)

3. Low Level Input - These left and right Line Level Inputs are normally used when the receiver/processor has line-level “pre-amp out ” or “subwoofer out” jacks. If a single cable mono or subwoofer source is connected to the BU1, a Y-cable must be connected to the subwoofer for full output.
4. Volume Control - This controls the volume level of the subwoofer.
5. Frequency - The Frequency adjustment determines the upper corner roll-off point for the BU1.

Schematic

TEST PROCEDURE

Equipment needed: Function/signal generator/sweep generator

Integrated Amplifier

Multimeter

Cables - line level (RCA) and speaker cables

General Function UUT = Unit Under Test

1. Connect both right and left line level inputs (RCA) to signal generator and UUT. Use Y-cable if necessary from mono source. VOLUME control should be full counterclockwise.

2. Turn on generator, adjust to 25mV, 50 Hz.

3. Plug in UUT; red LED should be ON. Turn VOLUME control full clockwise.

4. LED should turn Green; immediate bass response should be heard and felt from port tube opening.

5. Turn off generator, turn VOLUME control fully counterclockwise, and disconnect RCA cables.

6. Connect one pair of speaker cables to either high level input terminal on UUT. Cables should be connected to an integrated amplifier fed by the signal generator.

7. Turn on generator and adjust so that speaker level output is 1.0V, 50 Hz. Turn VOLUME control full clockwise.

8. Green LED should light, immediate bass response should be heard and felt from port tube opening.

Sweep Function

1. Follow steps 1 - 4 above, using a sweep generator as a signal source.

2. Sweep generator from 20Hz to 300Hz. Listen to the cabinet and drivers for any rattles, clicks, buzzes or any other noises. If any unusual noises are heard, remove driver and test.

Driver Function

1. Remove driver from cabinet; detach + and - wire clips.

2. Check DC resistance of driver; it should be 3.3 ohms.

3. Connect a pair of speaker cables to driver terminals.  Cables should be connected to an integrated amplifier fed by a signal generator. Turn on generator and adjust so that speaker level output is 5.0V.

4. Sweep generator from 20Hz to 1kHz. Listen to driver for any rubbing, buzzing, or other unusual noises.

marantz SR4500 – marantz PS4500 – Circuit diagram – Service mode

DSP 

POWER AMPLIFIER

VIDEO

SERVICE MODE

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Pioneer VSX D3S - power amplifier section circuit diagram

VSX D3S - Pioneer Elite power amplifier section schematic

Full Circuit [Amplifier]

Split

AOC2116S – 20 inch monitor – SMPS and Scaler schematic

AOC 2116s - TC7CMADDLWA6NG - TC7CMADDLWA6NN

Used semiconductors: AN9945N-T1-PF – TEA1530AT – STP10NK70ZEP(FET)

 SMPS and Back-light Inverter circuit diagram

SCALER (LVDS)

SMPS PWB-solder side

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ALTO MODEL: L12 - L16 - L20 – Professional Equalizer – Circuit Diagram - Testing

Please wait.  Might take some time to load.  Click on the schematics to Zoom in

Functions test
a. Input the proper AC power supply, turn on the main power, POWER LED will be illuminated (green). Then switch on PHANTOM power, PHANTOM LED will be illuminated (red), use a voltmeter to test the first pin and second pin of each MIC (MIC 1, MIC 2), the volt of phantom power should be 46V(±2V). then power off the switch.(Note: please turn off the switch when you are doing the steps of test procedure as follows)
b. Set all TRIM, LEVEL, EQ, AUX knobs to the position of 0, set PAN to the position of LEFT. All buttons to the position of OFF.
c. Input the signal from balanced sockets (MIC 1 & MIC 2), input the signal from  unbalanced sockets (LINE IN 3/4&LINE5/6)
d. Input the signal to the unbalanced AUX RENTURN sockets separately, test the balanced output (LEFT & RIGHT) of MAIN MIX OUTPUT, which should be 5dBu (±1dB) THD + N<0.003%.
e. Insert the RCA plug to L& R of TAPE IN separately:
First, press 2TK TO MIX button, test the unbalanced outputs (LEFT&RIGHT) of MAIN MIX OUTPUT, CONTROL ROOM and PHONE (need stereo plug for testing) separately, which should be 0dBu(±1dB) THD + N<0.006%.the output of TAPE OUT is 0dBu(±1dB)
Then release 2TK TO MIX button (OFF), no input from CONTROL ROOM, when press 2TK TO CONTROL ROOM, test the output, which is 0dBu (±2dB) THD + N<0.002%.

f. Input +15dBu 1kHz sine wave (load out 600Ω, BNC-Unbalanced) through LINE 1, when turn MAIN MIX LEVEL counter-clockwise to the minimize, all LEVEL LEDs will turned off, when turn MAIN MIX LEVEL pot clockwise to the
maximize, the LEVEL LEDs will be illuminated in sequence. test that whether the relating LED is illuminated when the level of output signal reaches the exactly value as LED shows . If so, test the maximize output level (before clipping) is
20dBu(±1dB) THD + N<0.1%.)
Adjust TRIM knob of CH 1 clockwise, PEAK LED will be illuminated (red). And test all PEAK LEDs from CH 1 to CH6
frequency response test
When Test the inputs of LINE 1, LINE 2, LINE 3, LINE 4, LINE 5, LINE 6 separately as follows, the frequency response curve of MAIN MIX OUTPUT (LEFT & RIGHT) (the preset of all knobs are the same as function test step 2.b)
a. Open S8RESP1.atl test procedure, press and release the LOW CUT switch, test the frequency response curve of LINE 1, LINE 2 LINE 3, LINE 4

b. Turn EQ HI &LOW knob to the MAX and the MIN (EQ MID at the middle), test the frequency response.

c. Turn EQ MID to the MAX and the MIN (EQ HI &LOW at the middle), test the frequency response.

Please wait.  Might take some time to load.

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Remarks: the frequency response test of normal instruments

a. Turn EQ LOW knob of the relating channel clockwise to the max (+15), the output is +15dBu(± 2dB), then turn EQ LOW knob of the relating channel counter-clockwise to the min. (-15), the output is –15dBu(± 2dB)

b. Input the signal at 2.5kHz, Turn EQ MID knob of the relating channel clockwise to the max (+12), the output is +12dBu(± 2dB), then turn EQ MID knob of the relating channel counter-clockwise to the min. (-12), the output is –

12dBu(± 2dB)

c. Input the signal at 15kHz, Turn EQ HIGN knob of the relating channel clockwise to the max (+15), the output is +15dBu(± 3dB), then turn EQ HIGH knob of the relating channel counter-clockwise to the min. (-15), the output is –15dBu(± 3dB)

DSP

a. Input the signal from MIC1, output the signal from MAIN MIX OUTPUT, turn AUX RTN2(DFX)clockwise to the MAX, turn PRESETS and VARATIONS knobs, the signal will be processed by DSP, if the level of the signal is over-high, PEAK LED will be illuminated to red, press DFX MUTE button, Bypass the signal, press the footswitch, which is connected to DFX FOOSWITCH, the signal will get out of BYPASS.

b. Input the signal from MIC 1 to MIC 4, output the signal from AUX SEND S1, turn AUX 2 /DFX TO AUX 1 counter-clockwise to the MAX., turn PRESET and VARATIONS knobs, the signal will be processed by DSP. (do not need to test L6 with this step)

Sampling test

Connecting L 6 to a power amplifier and speakers, listening to the sound, no noise is OK.

Company preset: turn all volume knobs to the MIN. other control knobs to the middle, all switches to the position of OFF.

CCE Studio Equalizer EQ6060 - Circuit Diagram

ICs used LM349 – LM339

Ics 701 – 706 => LN349

Ic 801 – LM339

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