Fixing Detuned or Clicking EP-40 Multisamples
Two problems spoil more EP-40 multisamples than anything else: notes that play out of tune, and clicks in sustained sounds. Both have simple causes and quick fixes. Here's how to track each one down.
You've built a multisample, sent it to the EP-40, and something's off. A run of notes plays sharp, or sustained sounds have a click in them. Annoying, but almost always an easy fix. Here are the two usual suspects, what causes them, and how to sort each one.
Notes that play out of tune
If a stretch of the keyboard plays consistently sharp or flat, the cause is nearly always the root note.
The root note tells the EP-40 the pitch a sample was recorded at, so it knows how far to shift every other key. Get it wrong, say a sample recorded at E is told its root is C, and every note in that zone shifts by the wrong amount. The zone plays in tune with itself, but sits at the wrong pitch overall.
How to spot it: play the root note of the suspect zone. If the sample doesn't sound at its natural, unshifted pitch there, the root note is wrong.
The fix is to set the correct root note so it matches the sample's actual pitch. If you're not sure of the pitch, re-run auto zone mapping and let it assign roots from your samples.
A subtler version: drift at the edges of a zone
Sometimes only the ends of a zone sound slightly off, even with the right root note. That's pitch-shift drift. The further a sample is stretched from its root, the less natural it sounds. The fix isn't the root note this time, it's to add more zones so each sample covers a narrower range and gets stretched less. Keep zones especially narrow in the low end, where shifting up is least forgiving. There's more on this in Root Notes and Key Zones Explained.
Clicks and pops in sustained notes
A click usually means the waveform has a sudden jump where it should be smooth. There are two places it happens.
At the start of the note: if a sample begins partway through the waveform rather than at a zero point, you'll hear a tick as it triggers. Trim the sample start to a clean point so it begins from silence.
At the loop seam: for sustained sounds that loop, like pads, organ or held notes, a click on every repeat means the loop start and end don't line up. The waveform jumps from one level to another at the seam, and you hear it. Let EP-PatchStudio's automatic loop-point detection find sensible points first. If you still hear a click, nudge the loop start or end so both sit at a zero crossing, a point where the waveform passes through the centre line. When both ends meet there, the loop joins smoothly.
While you're at it: distortion or clipping
If a sound is harsh or breaking up rather than clicking, the level is probably too hot. The EP-40's amplitude is global (there's no per-zone volume), so even out your loud and quiet samples before you import them. Normalising the batch first keeps the whole multisample at a sensible level.
Quick checklist
- A whole zone out of tune: wrong root note.
- Only the edges of a zone off: add more zones.
- Click at the note start: trim to a clean start.
- Click on every loop repeat: move the loop points to a zero crossing.
- Harsh or clipping: normalise levels before import.
Building your first one? Start with How to Make Multisamples for the EP-40 Riddim.
Get started
EP-PatchStudio is free to download, with multisample creation included.