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Audio Surround Decoder circuit diagram

Audio Surround Decoder circuit diagram

This circuit has been created to design a decoder circuit that will function in a module that produces surround sound audio.

The operation of the circuit starts up and transport the stereo surround sound signal quality information on the master volume circuit. This will drive the left channel connected to LCH Model TL072 IC1A IC1B and attached to the right channel Rch. The outputs of these operational amplifiers serve as the input buffer for the next stages of the circuit. IC2C is responsible for the sum of the signals from left and right to power the center speaker output, while IC2D is responsible for increasing the phase difference between left and right, which is encoded in the two channels and be fed to the rear speakers. It is necessary to ensure that the negative terminals from the rear speakers is not grounded, since it will only work in parallel with the main speakers.

The output of the power unit regulated IC2D takes audio to rear speakers. This would lead to the creation of sense of separation, according to the size of the room. This will incorporate signal amplifier IC5 MN3004 sound delay that has 512 steps. From IC4 MN3101 is a timing signal, which provides synchronization of IC5 as it functions as an oscillator in the circuit. C17 variable capacitor regulates the delay in the circuit. The presence of filters in the circuit is in order to avoid the noise that occurs during the process.

These filters can be adjusted to cut the frequencies above 8 kHz and below 100 Hz, to be able to drive the rear speaker. The rear speaker is small and that their entry is encoded with a bandwidth of 100 Hz to 8 KHz. The filters are built around the IC6A / B is also an output buffer. A potentiometer is placed on each output to aid in the adjustment and regulation of speakers and amplifiers. The energy supplied in the circuit is 15 V and each output can drive a single power amplifier.

List Compoment
R1-2-7-8-12-13-18-19-20 : 47Kohm
R3-4-5-6-21-22-34-35 : 10Kohm
R9-10-11-14-15-16-17 : 15Kohm
R23-24-25-33-36 : 100ohm
R26-27-28-31-32 : 100Kohm
R29-30 : 5.6Kohm
C1-8 : 47uF/25V
C2-7-9-14-23 : 47nF
C3-6 : 1uF/100V
C4-5-10 : 33pF
C11-12-15 : 10uF/25V
C13 : 82nF
C16 : 18pF
C17 : 100pF mini adjustable capacitor
C18 : 2.2nF
C19 : 4.7uF/25V
C20 : 100nF
C21 : 10nF
C22 : 180pF
C24 : 150nF
RV1-RV2 : 2 X 10Kohm Log. pot.
RV3-4 : 10K Log pot.
D1 : 1N4148
IC1-6 : TL072
IC2-3 : TL074
IC4 : MN3101
IC5 : MN3004