Refer to the table, maximum voltage supply for IC LM379 is 28V, it will will deliver 4W/channel. For LM377, maximum Vcc voltage is 18V single supply and delivers about 2W/channel. While for LM378, use maximum 24V regulated DC power supply and you will get 3W hifi audio power per channel.
Use heatsink on the IC to prevent overheating.
This is a video tutorial about how to a very simple audio amplifier based on the LM386 amplifier chip. It can be built for less than $20 (or might be less than $8 in some countries) and used to amplify any low level audio signal including a guitar, bass or mp3 player.
Watch the video: