Why Tilt Your Guitar Amp?
When your guitar amplifier is flat on the ground your sound will be projected between your feet and your knees. If you tilt your guitar amp back about 20 degrees your sound will be projected higher, and closer to your ears, and allow you to hear what you're playing at a lower volume than if your amp was flat on the ground. Even if your amp is on a stage that's elevated a couple feet higher than the ground where your audience stands (or sits), your guitar amp will still likely project your sound at a lower height than the ears of your listeners if it's sitting flat. Tilting your guitar amp not only directs your sound closer towards your listener's ears (and your own), it can also improve your tone by isolating some of the vibrations of your amp if you are tilting it with a wedge that can absorb some of those vibrations. When tilting your amp with a wedge that can absorb some of those vibrations you will improve the quality of your tone by preventing the floor, furniture, and sometimes microphones from picking up some of the vibrations that might otherwise be transferred to them when not using a wedge. For all of these reasons, tilting your guitar amp back is beneficial when practicing at home, recording in the studio, or playing for a live audience.