Here the 18W audio amplifier circuit which powered by IC HA13118 as the main component.The type of this amplifier is bridge amplifier since the output line does not grounded.
The supply voltage required for this circuit is 8 – 18V DC, at least 1 to 2 Amps. Maximum output power will only be obtained with a power supply of 18V at greater than 2 A, using a 4 ohm speaker. The power supply should be well filtered to reduce mains hum, a regulated supply will reduce noise even further. Extra filtering is unnecessary if operating from a battery supply.
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