Circuit Amplifier LM317
Use a good heatsink for the LM317 IC and adjust the 5K variable resistor so that you have 4.5V on 10Ω resistor (or LM317 pin 2, Vout).
IC LM317
You probably know that LM317 IC is used as an adjustable
voltage regulator, but did you know it can be used as an audio amplifier This is a class A audio amplifier built with LM317 that delivers a maximum 1W audio power.