Changing Audio Volume Volume levels for audio tracks in Metro can be changed several ways. You can change the volume in real time (maintaining the original audio data) using the faders in the Instruments Mixer window. To make a permanent change to the audio data (known as an offline edit), you can use commands in the Edit menu's Audio submenu: Scale Amplitude, Fade, Normalize, and Group Normalize. For this tutorial, we'll investigate only one of the methods, the Normalize command. This command allows you to maximize the volume in any recorded audio, helpful before you begin mixing a song. It does this by searching through the current audio selection to detect the highest amplitude peak, then scaling the rest of the audio up to match. You can control whether Metro scales it all the way up to its maximum amount with the Normalize dialog box and the Change audio to 'N' % of maximum field. The Change audio to 'N' % of maximum field accepts values between 1 and 500, a 100% amplitude setting scales the detected amplitude peak to 0 dB (to the maximum volume before distortion, or 'clipping,' occurs). The overall affect of applying the Normalize command increases perceived loudness across an audio selection. To normalize your audio, use these steps: Select a small portion of audio. Choose Audio and Normalize from the Edit menu and see what it does for your waveform and the playback volume! Now that we are editing audio, let's proceed to Adding Effects in Real-time.