In part one of this guide we imported an MP3 file into ACID Pro 4 and used the beatmapper function to analyse the tempo of the song. Then we created an audio clip in the timeline and used the loop playback option to listen to the result. This week, we take you through the process of constructing more loops and arranging the remix.
Loops, beatmaps, one-shots and MIDI
ACID channels run horizontally across the screen. Together, the channels are known as the timeline. Each channel can contain one or more clips or loops, the contents of which depend upon the type of channel. For example, our remix contains one channel - a beatmapper channel. Beatmapper channels are designed for extracting regions from long audio files. They are stretched in real time to match the song's tempo, and they can be tweaked from either the timeline or the chopper window without the need to edit the audio in an external wave editor. Beatmapper channels are therefore perfect for remixing songs. See Figure 1 - Channel types .
Aside from beatmapper channels, there are three other channel types available in ACID 4 - loops, one-shots and MIDI. Loops are small sections of audio that are loaded into memory and can be repeated automatically in the timeline. Like beatmapper channels, loops are stretched in real time to match the tempo of the song. One-shots are either short or long pieces of audio that are played from the hard disk. They are good for non-rhythmic sounds such as speech or ambience. MIDI tracks are used to play either external MIDI equipment (such as synthesisers) or virtual software instruments.
Re-using beatmapper channels
We left our remix last time with a single audio clip in a beatmapper channel. To create another loop from the song, right click the audio track and select "duplicate track". See Figure 2 - Duplicating the track .
Then right-click the audio clip in the new track and choose "select in chopper". At the bottom of the screen, your song will be displayed in the chopper window with gridlines at each beat position. See Figure 3 - The chopper window .
From here you can select different parts of the song and, when you have a nicely looped section, you can add it to the timeline by dragging and dropping it back to the new channel. By repeating this process, you can create as many loops as you like.
If you find that some loops are out of time with the song, you can re-align the beat markers in the track by holding down
Even though you can trim individual beatmapper clips in both the chopper window and the timeline, if you ever want to re-beatmap a track, simply right-click on the channel and select "properties". From there you simply click the "Stretch" tab and then click "Beatmapper wizard".
From beatmaps to loops
Beatmapper channels are great for long sections of audio or playing back entire songs, but if you want to repeat a section of the song, you'll want to use a loop channel instead. To do this, open a clip from a duplicate of your beatmapper channel in the chopper (right-click the audio clip to do this). Find another section of the song to loop and tweak the loop points so it loops smoothly. Instead of dragging it into the beatmapper channel, however, right click it and select "chop to new track" (
Composition and effects
Once you have a selection of loops from your original song, it is a straightforward process of drag and drop, and copy and paste, to create a new arrangement! You can import beats and riffs from other songs as well. To spice things up and make sure your loops don't drown each other out when they play simultaneously, you should experiment with some equalisation and effects. To add an effect to a channel, click the little green and orange button next to the channel volume slider. See Figure 5 - Adding effects to a channel .
Mixing down to MP3
Once you're happy with your remix, you can render the whole composition down to an MP3 file or even burn it straight to CD. To export an MP3, select "Render as" from the file menu. To burn CD audio, use the tools menu and choose "Burn track-at-once audio CD". See Figure 6 - Burn straight to audio CD .