PreSonus Blog

Why Overlap Correction is Totally Cool

 

Studio One’s Overlap Correction feature for Note data isn’t new, but it can save you hours of boring work. The basic principle is that if Note data overlaps so that the end of one note extends long enough to overlap the beginning of the next note, selecting them both, and then applying overlap correction, moves the overlapping note’s end earlier so that it no longer overlaps with the next note.

My main use is with keyboard bass. Although I play electric bass, I often prefer keyboard bass because of the sonic consistency, and being able to choose from various sampled basses as well as synth bass sounds. However, it’s important to avoid overlapping notes with keyboard bass for two main reasons:

  • Two non-consonant bass notes playing at the same time muddies the low end, because the beat frequencies associated with such low frequencies are slow and disruptive.
  • The sound is more realistic. Most bass parts are single-note lines, and with electric bass, there’s usually a finite amount of time between notes due to fingering the fret, and then plucking the string.

One option for fixing this is to zoom in on a bass part’s note data, check every note to make sure there aren’t overlaps, and shorten notes as needed. However, Overlap Correction is much easier. Simply:

 

  1. Select All Note data in the Edit View.
  2. Choose Action > Length, and then click the Overlap Correction radio button.
  3. Set overlap to -00.00.01.
  4. Click OK.

Normally I’m reluctant to Select All and do an editing function, but any notes that don’t overlap are left alone, and I haven’t yet run into any problems with single-note lines. Fig. 1 shows a before-and-after of the note data.

Figure 1: The notes circled in white have overlaps; the lower copy of the notes fixes the overlaps with the Length menu’s Overlap Correction feature.

Problem solved! The reason for setting overlap to -00.00.01 instead of 00.00.00 is because with older hardware synthesizers or congested data streams, that very slight pause ensures a note-off before the next note-on appears. This prevents the previous note from “hanging” (i.e., never turning off). You can specify a larger number for a longer pause—or live dangerously, and specify no pause by entering 0.

Also, although I referenced using this with keyboard bass, it’s useful for any single-note lines such as brass, woodwind, single-note MIDI guitar solos, etc. It can also help with hardware instruments, including electronic drums, that have a limited number of voices. By removing overlaps, it’s less likely that the instrument will run out polyphony.

There’s some intelligence built into the overlap correction function. If a note extends past another note, there won’t be any correction. It also seems to be able to recognize pedal points (Fig. 2).

 

Figure 2: Overlap Correction is careful about applying correction with polyphonic lines.

Selecting all notes in the top group of notes and selecting Overlap Correction didn’t make any changes. As shown in the bottom group of notes, preventing the pedal point from overlapping the final chord requires selecting the pedal point, and any of the notes in the last chord with which the pedal point overlaps.

It’s easy to overlook this gem of a feature, but it can really help with instrumental parts—particularly with keyboard bass and solo brass parts.

  • I’d always done these fixes manually until I stumbled on this. I often wonder what other things are in Studio One that would be really useful, but I just haven’t found them yet…!

  • Boomer Rube

    Needed this, Craig. I been doing this manually as I detected the odd undetectable a note here & there. Thanks.

  • Thanks for your feedback, glad you like it!

  • Wzrd Wizitch

    Ok that’s extremely handy to know! Thanks so much for sharing.