什麼是pre-out??

For AV amplifier, most of the cases you can use it to direct output to speakers for sound reproduction. However, if you want less burden to the AV amplifier or better power, you may use the pre-out to connect to other amplifiers with pre-in so that some or all of the output to speakers will be done by a more powerful amplifier or by more than one amplifiers . This of course requires more investment, space and technical knowhow in order to give you a good result.