I have a Sony HT-K215 HT system. It is a 'satellite' system (small speaker system) Check this out http://www.sony.com.sg/consumer/cons...m/ht_k215.html

Now the question is what is the value of db louder than Front L/R for Center, Surround and Subwoofer?

Being able to adjust the various speakers to increase or decrease the db or decibels allows you to match the speaker output level for all your speakers so they are properly balanced. To do this you need a SPL meter and a test tone or video essentials. By dialing everything into the same level you get a cleaner sound field in your 5.1 set up. Hope this helps.