Matt circuit

This circuit use IC TDA1004A to main operation .IC is very nice and durable if used properly and correctly, by the way supply the correct voltage , don't supply more voltage than 20 volts, because it can damage the IC. This circuit suitable for subwoofer speakers, but this amplifier  is mono.See schematic and troubleshooting below : If the circuit above not working , posible cause is on : Supply voltage. IC Damaged or installation inverted. Component damaged . Installation components inverted. Line break PCB. Input not connected or input connect to ground. Output speaker not connected.

This power amplifier can use IC TDA1510 or TDA1515, minimum voltage require 6 volt and maximum voltage require 18 Volt, Voltage with DC supply voltage.Power output  2x 30 Watt stereo amplifier , with 2 ohms impedance , its is low impedance . You can use the fullrange or woofer speakers. see schematic below :

The linear power supply, shown in the schematic, provides 0-30 volts, at 1 amp, maximum, using a discrete transistor regulator with op-amp feedback to control the output voltage. The supply was constructed in 1975 and has a constant current mode that is used to recharge batteries. Circuit diagram : 0-30 Volt Laboratory Power Supply Circuit Diagram With reference to the schematic, lamp, LP2, is a power-on indicator. The other lamp (lower) lights when the unit reaches its preset current limit. R5, C2, and Q10 (TO-3 case) operate as a capacitor multiplier. The 36 volt zener across C2 limits the maximum supply voltage to the op-amps supply pins. D5, C4, C5, R15, and R16 provide a small amount of negative supply for the op-amps so that the op-amps can operate down to zero volts at the output pins (pins 6). A more modern design might eliminate these 4 components and use a CMOS rail-to-rail op-amp. Current limit is set by R3, D1, R4, R6, Q12, R10, and R13 providing a bias to U2 that partiall...