Here is another trick for using a delay to create a bit of a stereo effect on a mono track. The basic idea is to pan the mono track slightly to one side (one to three o’clock should do it) and add a delay that is panned about the same amount to the other side (nine to eleven o’clock). Adjust the delay time to produce a sound you like for your mix, and there you have it! It is a fairly simple technique that can be used to push something like a supporting keyboard track out of the center of a mix but allows you to still keep it turned up in volume. Following is a description of how to do this trick in REAPER and more details on what kinds of delay settings I think sound good.
This delay trick will require three tracks in your home recording software, though only one of the tracks will have an audio clip on it.
- Create a track folder
The first of the three tracks will be the main track for the mix. REAPER calls this a folder track and you create it by clicking the folder button on the track (circled above on the organ track). When you click this folder button all tracks after it are inside the folder. Click the folder button on another track to make it the last track in the folder (circled on the keys delay track above).
- Configure the track routing
Click the io button on the main audio track to bring up the Routing dialog for the keys track. Add a new send by choosing the keys delay track from the dropdown list of tracks. Set the send to be Post-FX (other options are Pre-FX and Post-Fader). If the send were post fader, we would not be able to pan the two tracks independantly. If you keep it post fx, then you can add eq, compression or any other effects to the main track and the sound will also be corrected on the delay track.
- Pan the tracks
The two tracks inside the folder should be panned a bit to opposite sides. In my example the main track is 28% to the right while the delay track is 31% to the left.
- Add the delay effect
Add your favorite delay plugin to the delay track and you are ready to configure the effect!
Delay effect settings
The ideal delay time is in the range 30-65ms. On the shorter end of the scale you have to listen for phase cancellation and comb filtering in your signal. At the longer delay times you have to be careful of a slapback type of sound. Do what is right for your mix, but in my example I have set the delay time to 45ms.
Delay feedback controls how many echoes are produced. We don’t want a typical echoing sound so set the delay to produce zero echoes. This means putting the feedback at zero.
We want the mix on our delay plugin to be 100% wet since we already have a dry track. If your delay has a mix control, set it to be fully wet. Delay plugins with independent wet and dry levels should have their dry level set to all off and wet level set to unity gain. Whatever your delay effect calls it, just make sure you are hearing the delayed signal only.
Play back your mix and you should hear the keyboard track has opened up a bit and moved out of the center even though it still seems to be imaged center. Here are some audio clips to demonstrate the sound I got with my settings.
Here are some ideas if you want to get more experimental with your implementation of this delay technique.
- Panning positions
You can create subtle variations on the stereo imaging by altering the pan positions of your two tracks. Changing the panning of the dry track will alter the left-right position of the track in the mix while changing the panning of the delay track will alter the sonic quality of the stereo image.
- Pan to one side
An interesting effect can be created by panning the original track and delay track to the same side. Try panning the delay hard left and the dry track only 25-50% left. When panning to the same side, the key is to remember to keep some spatial separation between the two tracks. You can pan them the same amount to the same side but what you will have then is a mono sound that is imaged off center instead of a stereo sound.
- Change the levels
You will typically keep both tracks at the same volume level but try experimenting here. You can make the delay track a few dB quieter than the dry track. For a less natural sound you can even make the delay track a few dB louder than the dry track.
- Pseudo-reverse delay
This is the least natural sounding application of this technique but can be used to create some interesting sounds. If you have a 45ms delay on the wet track, try moving the audio clip forward by 45ms. This would make all the keyboard notes hit 45ms early which will sound terrible alone, but the delay track will be playing in perfect time. Make the dry track 3-6dB quieter but keep the delay track at the normal volume. This is similar to the reverse reverb trick but without any actual reversing.
Your home studio is your playground, have fun!