Stereo Speaker Protection

This is the stereo speaker protection circuit, provides stereo speaker protection and prevents switch-on clicks and DC components on the output of the amplifier connected. Stereo Speaker Protection Circuit diagram :
Speaker Protection Components List:

1. R1,R2 : 3K3
2. R3,R4,R5,R6,R7 : 8K2
3. R8,R9,R10,R11 : 330K
4. R12,R13 : 18K
5. R14,R15,R16,R17 : 47K
6. R18 : 47
7. R19,R20 : 680
8. R21,R22 : 100K
9. R23,R24,R25,R26 : 1K2
10. C1,C2,C3,C4,C5,C6 : 1?F
11. C7,C8,C9,C10 : 100?F
12. C11 : 220?F
13. C12,C13 : 470?F
14. D1,D2,D3,D4,D5,D6,D7,D8,D9,D10 : 1N4148
15. D11,D12,D13,D14 : 1N4007
16. ZD1 : 6V8
17. T1,T2,T3 : BC547B
18. T4 : BC517
19. LD1 : Red (ERROR INDICATOR)
20. LD2 : Yellow (WAIT INDICATOR)
21. RY1,RY2 : VR15M121C (12VDC – 15A – 1C)
22. Transfo (1,2VA – 2 x 6V / 2 x 0,1A)
23. IC1 : LM324

Circuit Notes:
This circuit uses center tap transformer and the power supply circuit design already provided in the schematic diagram. It powered with 6V dual polarity power supply.

This circuit available in kits, you may order the kit online. The manual assembly of the kit can be download at the end of this post.

This stereo loudspeaker protection will protect the loudspeakers against the switch-impulsions and the direct current component on the output of the connected amplifier.
Suitable for:

1. Amplifiers with symmetrical power supply
2. Amplifiers with asymmetrical power supply.
3. Specifications :
4. Switch-delay: 6 seconds
5. DC protection: +1V/-1V
6. Max. input voltage: 200Vpp + DC
7. Max. switching current: 10A
8. LED indication for: WAIT (switch-on delay) and ERROR (DC on speaker output)
9. Supply voltage: 220VAC .Read more http://circuitdiagram.net/speaker-protection-circuit-stereo.html

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