Ever have a guitar, drum, or percussion tracks that's a bit timey-wimey and loosey-goosey? Maybe your mandolin player was a bit slow on tracking day? Never fear -- MK Slicer is available in REAPER to help you get things back closer to the grid.
MK Slicer
MK Slicer is a script available for Reaper that helps us improve the timing of audio and MIDI tracks. We're covering audio here.
With MK Slicer, you can add guides to your audio. The guides can be ether based on your timing grid, or transients in the signal. The guides show up as orange lines in MK Slicer. You can either slice the audio track based on the guides, or add stretch markers based on the guides.
Then MK Slicer can quantize the audio to the grid, or you can move the slices/stretch markers manually.
If it sounds complex, it's not. The video above will take you though it.
Using MK Slicer
And here is the interface (click to enlarge).
MK Slicer Interface
MK Slicer Interface
Let's cover the relevant menu items and controls.
Grid Selection
Along the top-left, you'll see the possible grid selections. This will put little green lines in at the top of the interface window. You can select anywhere from whole notes to 64th notes. Triplets and swing feel (with plus and minus swing percentages) are also available.
How to set the grid: Set this to the fastest the part is playing. In other words, if you're fixing the timing on a guitar part that's playing 16th notes, set the grid to 1/16, so you can easily see how the playing lines up to the grid.
3rd Column From The Left (Center Bottom)
MK Slicer Middle Column Menu
In this column, you'll find one of the most important settings, that you should set right after you set the grid. You'll see either 'Guide By Transients', or 'Guide By Grid'. 'Guide By Transients' will set the orange guide markers based on detecting transients, and 'Guide By Grid' will put markers on the grid lines.
I usually use 'Guide By Transients'. If you select transients here, now to the the lower-left column and adjust those parameters until MK Slicer is detecting transients accurately. Then come back and use the menu items below.
In this center column, you'll also see 'Slice', 'Q', 'Markers', 'Q', 'Offset', 'QStrength' and XFades'.
If you want your audio sliced on the orange guides, click 'Slice'. If you want it quantized, click the 'Q' next to 'Slice'.
If you want your stretch markers placed on your audio based on the orange guides, click 'Markers'. If you want it quantized, click the 'Q' next to 'Markers'.
'Offset' will set the guides early or late by a specified number of milliseconds. It's useful if you want to have a snare drag or rush, for instance.
'XFade' controls the amount of crossfade on sliced items.
You can generally leave 'Offest' and 'XFades' alone.
'QStrength' sets the percentage you want to use when you quantize. 100% will snap every transient to the grid. 50% will move every transient that's off, 50% closer to the beat. Keep in mind that sometimes, timing imperfections add to the feel of a song.
Also, if you're stretching audio, that can mean artifacts and blips in the sound, especially with extreme corrections.
Pro Tip: You can use MK Slicer to place stretch markers on 16th notes and then manually go through the track and adjust just the areas that seem off to you.
Lower Left Column: Get Item
If you don't see a waveform come up in the interface, you can left click on on a piece of audio, and then click on the Get Item, and that will get your item.
Lower Left Column: Filters
Below 'Get Item' that are the filters, which affect transient detection, but not the audio itself. The filters work when 'Guides By Transients' is selected. Why would we use filters?
Let's suppose you have a kick drum you want to quantize. You want to have MK Slicer put a guide (orange line) in every time the drummer plays the bass drum. But there's a lot of hi-hat bleeding into the kick drum microphone. MK is detecting transients (sudden attack of sounds) from both the kick and hat, but we only want the kick.
MK Slicer Lower Left Menu
We could set the high cut filter to maybe 200Hz, and it would greatly reduce the amount of hi-hat being detected. Again, this doesn't affect the audio, only what MK Slicer sees as a transient.
How to set the filters: 90% of the time, just leave them alone. But if you've got mic bleed, or an instrument with a wide frequency range, but you only want to track the transients, you can adjust the filters to reduce the frequencies that are confusing the transient detection.
For instance, a tambourine track might have low-end information that could be picked up as a transient, but it's really the sparkly high end that spanks. You want to use the high end to guide MK as to where the transients are. Keep pushing the low cut up (left click and drag to change the filter frequency), until you see the guides being placed more accurately.
2nd Lower Left Column:
In the next column over, we have 'Threshold', 'Sensitivity', 'Retrig', and 'Reduce'.
MK Slicer 2nd Column Menu
Threshold sets the level at which MK Slicer detects a transient. As you move the threshold, you'll see to faint lines more apart/together. Anything that's got enough level to be a transient should be contained within the two lines. Anything that's not a transient should not reach the lines. This helps you visually to set the threshold to catch transients, but not other sounds.
Sensitivity controls the sensitivity of the threshold. In general you can leave it alone. But if you've finagled the threshold as best you can, and MK isn't detecting what you want, the sensitivity can help you fine tune it.
Retrig is a timing setting that helps MK Slicer know how often you want a transient to be detected. Retrig tells MK Slicer not to detect another transient for a specified number of milliseconds. If the audio is meant to be at 16th notes, and MK Slicer is detecting transients in between 16th notes, you can try setting 'Retrig' for somewhere in between the duration of a 32nd note and a 16th note (this depends on your tempo, of course).
Reduce just reduces the number of guides MK Slicer Places on the audio. Have too may? You can try 'Reduce'.
When Not To Use MK Slicer
If the audio you're working with is not very long, it's probably better just to go in a place stretch markers or slices manually -- and adjust them manually. It's faster. If you have a 5 minute long track, that's a lot of work.
You can also use MK Slicer just to place stretch markers or slices. You don't need to use the quantize function. You can manually go through the track and adjust only the areas that seem off to you. This is a good way to go if you have a philosophy of minimal processing, but don't want to spend all day manually placing markers or slices on every 16th note of a 5 minute track.
About MK Slicer
More MK Slicer Resources in the REAPER Forum
Who Made MK Slicer?
According to the good people over on the REAPER forum, users cool, eugen2777, MPL, MyDaw, and Archie were involved in creating MK Slicer. Thanks to all!
