An Audio Signal Distributor Circuit is an important tool that helps divide an audio signal into multiple output channels without losing the quality of the original sound.
The specific circuit we are talking about is a Audio Signal Distributor Circuit with Three Outputs designed using an operational amplifier called the IC NE5532 along with transistors known as BC337 and BC327.
This setup ensures that the audio signals are shared equally among three different outputs.
This kind of circuit is really useful for many things like sound systems, headphone splitters and setups that need to send audio to different rooms.
Circuit Working:
Parts list:
| Component | Specification | Quantity |
|---|---|---|
| Resistors | All 1/4 watt unless specified | |
| 560k | 1 | |
| 1k | 1 | |
| 2.2k | 1 | |
| 2.7k | 2 | |
| 330Ω | 3 | |
| Potentiometers | 100k | 2 |
| Capacitors | Electrolytic 100μF 25V | 4 |
| Semiconductors | IC NE5532 | 1 |
| Transistors BC337, BC327 | 1 each | |
| Zener diode BZX79C18 | 2 |
In this article audio signal enters the circuit through a specific input terminal and moves through a series of resistors R1, VR1, VR2 that help match the impedance and provide biasing.
To stop any direct current from getting into the operational amplifier capacitor C1 acts as a blocker.
The IC1 NE5532 is set up to work as a buffer amplifier.
The audio signal is processed at pin 3 which is the non inverting input and the amplified output can be found at pin 1.
To keep the signal clean and remove any unwanted DC noise capacitor C2 is used for decoupling.
Zener diodes D1 and D2 along with resistors R4 and R5 help provide stable positive and negative voltage supplies that the operational amplifier and transistor stages need.
This setup ensures that the circuit works well even when the input voltage varies between +20V and +35V.
The output from the operational amplifier is then sent out through three channels Audio output1, Audio output2, Audio output3 using resistors R6, R7, R8 to evenly split the signal.
Additionally, transistors Q1 BC337 and Q2 BC327 are used to boost and stabilize the current for the positive and negative signals.
To improve the audio quality capacitors C3 and C4 are added to further smooth out the signal.
Formulas with Calculations:
To design you own circuit you need to follow the below mentioned formulas for Audio Signal Distributor Circuit:
Voltage Regulation:
Zener voltage: Vz = 18V for D1 and D2
Resistor values for zener operation: R4 = (Vin – Vz) / Iz
For example, if Vin = 20V and Iz (zener current) = 2.7mA:
R4 = (20 – 18) / 0.0027 = 740 ohms = 2.7k
Input Impedance:
Input impedance (Zin) is determined by R1, VR1 and VR2:
Zin = R1 || (VR1 + VR2)
Assuming R1 = 560k, VR1= 100k, VR2 = 100k:
Zin = 1 / [(1 / R1) + (1 / (VR1 + VR2))]
Zin = 1 / [(1 / 560k) + (1 / (100k + 100k))]
Zin = 50k
Gain of Operational Amplifier:
The NE5532 is used in unity gain so:
Vout = Vin
Output Current:
The output current is determined by the transistors and resistors R6, R7 and R8.
For example, if the output voltage is Vout = 1V and the resistor R6 = 330Ω:
Iout = Vout / R6 = 1 / 330 = 3.03mA.
How to Build:
To build a Audio Signal Distributor Circuit with Three Outputs following steps you need to follow while assembling:
- Gather all the components as mentioned in the above circuit diagram.
- Connect pin 1 of IC1 NE5532 to positive of capacitor C2 and negative of capacitor to Audio output1, Audio ouput2, Audio ouput3 through resistors R6, R7, and R8, connect pin 1 to pin 2 of IC1 NE5532 through resistor R5.
- Connect pin 2 of IC1 NE5532 to GND through resistor R2 and capacitor C1
- Connect pin 3 of IC1 NE5532 to center leg of VR1 pot, upper leg to center leg of VR2 pot, and third leg to GND.
- Connect the resistor R1 from pin 3 to GND.
- Connect pot VR2 center leg to center of VR1 and 2nd leg of VR2 to Audio input and GND.
- Connect pin 4 of IC1 NE5532 to emitter of transistor Q2, collector of transistor Q2 to -VCC of -20V to 35V and base of Q2 negative of capacitor C4 and positive of capacitor to GND.
- Connect from base of Q2 a D2 diode and GND, and after D2 diode connect a resistor R5 to VCC of -20V to 35V.
- Connect pin 8 of IC1 NE5532 to emitter of transistor Q1, collector to +VCC +20V to 35V, connect base of Q1 to positive of capacitor C3 and negative to GND, connect from positive supply resistor R4 and diode D1 and GND
Conclusion:
The Audio Signal Distributor Circuit with Three Outputs is a great way to take one audio signal and split it into three outputs without losing sound quality.
It uses the NE5532 operational amplifier, which helps keep the sound clear and true to the original.
Plus, the transistor output stage gives enough power to handle the speakers or other devices.
This design is easy to understand and strong making it perfect for both home audio systems and professional setups.