Home Theater Hacks

Hack #26. Use Gain Offset to Regulate Volume

Avoid the annoying volume switch between television programs, DVDs, and even different CDs using your receiver's gain offset feature.

Sometimes in the course of purchasing high-quality audio equipment, newcomers notice nuances in the sound of their CDs that they never heard before. One of the most common complaints stems from the perceived volume differences between compact discs. Some recordings, usually older reissues of material recorded before the mid-1980s, seem considerably quieter than more recent releases. This difference becomes even more apparent when two discs are played back to back on a carousel CD player or from your favorite MP3 jukebox.

Understanding Dynamic Range

Compact disc is a digital medium, which means it has a specific maximum sound level it is able to carry. The loudest amount of sound you can put on a CD is zero. Because zero is the maximum, all other sound works backward from that point and is expressed as a negative number (–10, –20, etc.). All CDs have this maximum; think of it as a global speed limit for the format.

Most consumers don't understand why, if all CDs have the exact same maximum level, some CDs sound so much louder than other recordings. This extra loudness is especially apparent in modern recordings. Most folks assume older recordings sound softer because they don't exploit the full volume level available on CD. They assume the music is simply recorded at lower levels, but this is rarely the case. ...