This is extremely useful information when performing precision sample-accurate file slicing and post slice editing while maintaining sample-accurate zero-crossing points.

In the Sample Editor, select the Hand Tool and click hold the selected area to display not only the Start and Length (Count) in Samples but also the all important End point value in Samples.

Fig 1. Sample Editor Help Tag showing Start value, End value and Length (Count).

Now you can be sure to match exactly a region start point having edited the preceding region’s end point. A common scenario when adjusting regions to have boundaries on zero-crossing points.

Further Info…

Having easy access to File Start, End and Length information will seriously increase your sample editing accuracy when editing and re-editing.

The Sample (Selection) End point is omitted from the Logic Sample Editor info display (Fig.2) and also from the Help Tag when clicking a region in the Arrange Pane (Fig.3). Having quick access to adjusted End Point information of Region [A] ensures quick and confident Start Point editing of Region [B] to be consistent with the Region [A] End Point.

Fig 2. Sample Editor info Display showing Start Point and Length.

Fig 3. Audio Region Help tag in the Arrange pane showing Start Point and Length.

When editing complex material such as bounced mixes, the waveform display can become difficult to gauge with respect to matching cut points of one region’s start point to be consistent with that of the previous region’s end point after updating that region’s start or end point. A common task when preparing loops and libraries.

Fatigue from repetitive editing can easily play a part in performing inaccurate cuts and splices. These characteristics will often only become obvious upon triggered playback and sequencing of regions, particularly in a phrase loop situation.

A common problem arises when exporting cut loops from Logic to an external unit such as an Akai MPC, where inconsistencies between tempo analysis that exist between the two platforms result in problematic and less than smooth playback.

Often, the ‘fix’ involves one of the following:

1. entering  subtle tempo change values as part of the midi sequence playback data to accommodate smooth transitions between loops of slightly unequal length. This way the edits maintain authentic pitch and time characteristics, at the expense of inconsistent temporal playback.
2. manually, or via batch processing, applying time-stretching algorithms to scale regions to a fixed length. This can result in unwanted audio anomalies.

-MC-

Dealing with unwanted Clicks, Pops & Noise artifacts in Logic is handled by the Silencer Tool in the Sample Editor’s Factory Menu.

Spike Reduction

Set the Strength slider to the far left, Off. This turns off Noise Reduction. Only the Spike Reduction function is active.

Set the threshold at which level Spike Reduction is applied by adjusting the Sensitivity slider. High is for small spikes, Auto is for automatic threshold control, Low will identify most Peaks as Spikes.

Adjust the Method slider to select the type of processing algorithm.

• Smooth a selection with Gentle and 
• make Drastic changes with Aggressive.
• Re- stands for Rebuild. A synthesized signal is created in place of the selection based on the analysis  of audio  surrounding the selection.

Pops & Clicks can also be removed manually with the Pencil Tool in the Sample Editor. For accurate redrawing, zoom right in on the offending spike and enable Show as Sample & Hold from the view menu for Sample Accurate Editing.

Click the Process Button to apply and audition your settings. Undo a process if it’s not quite right and make necessary adjustments.

Noise Reduction

Enable Noise Reduction by adjusting the Sensitivity slider to the far left (Off).

Adjust the Strength slider accordingly.

Click the Process Button to apply and audition your settings. Undo a process if it’s not quite right and make necessary adjustments.

Mixed Spike & Noise 

The Silencer Settings in Figs 1.0 and 2.0 tackle a slice of audio that exhibits a mixed problem of 2 or more subsequent glitch characteristics, veiled in an region of predominantly fuller frequency audio. Fig 1.0 has a more drastic effect and significantly attenuates the overall Gain of the selected audio. Fig 2.0 maintains acceptable Gain while softening the offending characteristics.

Fig 1.0

Fig 2.0

When selecting Audio Regions in the Audio Window or Audio Bin, it would be very useful to display the start point of a selected region in Sample values in the context of the overall audio file.

Scenario

A typical example is rendering a multi-track mix to stereo or even editing a bounced file that may require further edit cuts.

Once you have cut an audio file or region a new region representing that cut is automatically created. Removing this cut from the Arrange area leaves a gap and you then fill this gap by shifting one of the regions to meet the other. 

Selecting any of the shifted regions in the Arrange area will display its Start Point relative to the Timeline and subsequent length in the Help Tag. There is no reference to the cut region’s start point (anchor point) in relation to the overall audio file that it originates from.

The only way to access this absolute time specific information is by selecting the region in the Audio Window (not the Audio Bin) and viewing the info display of the selected region in the Sample Editor. Selecting the same region in the Arrange Area will show a region start point and region length relative to the time-line and not the mother audio file.

Why is this important? Here’s why…

If parametric adjustments are required at the multi track stage prior to rendering (bouncing) and after having made cuts to the bounced file, it is inevitable that a fresh bounce of the multi track stage will require cuts at the exact same points as the previously edited bounce.

Having immediate visual access to sample accurate start points, relative to the overall audio file time, of a region that has been shifted left or right to bridge a cut, will enable quick application of the scissor tool or split by playhead function on the latest bounce to replicate exactly the cut points of the previously edited bounce and therefore quickly dispose of unwanted regions. 

This information would be a valuable inclusion as an optional display along side the Region Length field in the Audio Window and Audio Bin.

Only by selecting a region in the Audio Window can one access the true Region Start Point value relative to the mother audio file and even then, this information is only available via the Sample Editor info display.

To summarize, I have written to  Apple’s Logic Team to please offer a Region Start Field as well as a Region Length Field in the Audio Window.

For sample Accurate editing in the Arrange Area, set Snap: to Samples. In the Sample Editor set View to Samples to reference the correct Region Start value in the info display.

-MC-

The anchor sets a temporal reference point for an Audio Region.

When you move a region in the Arrange area, Logic Pro displays the position of the anchor in the help tag, and snaps the region’s anchor to the selected Snap menu grid division. 

It is an Orange indicator in the Sample Editor and Black in the Audio Bin Window (Command 9).

A newly created Audio FILE always has the Anchor and Region Start points at the beginning of the file.

Positioning the Anchor to lock to an obvious amplitude peak of a swell sound or attack point (Kick Drum) in a drum loop will force the region to snap to the grid of the Arrangement (as defined in Transport Bar, below the Time Signature value), using the anchor as the pivot point. These are good examples of beat / grid time reference points. Therefore, when moving an Audio region with a well-positioned anchor point, you can be confident that the Audio Region will maintain its temporal relationship to your arrangement as you move it back and forth.

Positioning the Anchor at the highest (single bit) zoom resolution will ensure tight synchronization and quantization between the Audio file and  MIDI regions. * of course offset anchor placement could lead to interesting ’humanized’ synchronization or rather more desirable ‘idiosyncratic’ playback akin to early sample based recordings such as 1980’s Hip Hop which interestingly enough, was often down to ‘badly’ looped sample editing as much as the conflicting grooves of layered sample loops.

The Help Tag displays the Anchor point rather than the Region Start point when you move an Audio Region.

• Any changes to the Anchor point will change the relative position of the audio region in the Arrangement.

To maintain the Audio Region position in the Arrangement:

In the Sample Editor Choose Edit > Compensate Region Position Ctrl C.

• When active, moving the anchor won’t change what you hear in the Arrange area.
• When inactive, moving the anchor changes the position of audio regions in the Arrange area. The region shifts in relation to the Time Axis, while the Anchor remains tied to the same bar value and is marked by a dotted line.

Anchor points can not be positioned before a Region Start Point.

Hold down Option  while moving the End Marker of an Audio Region to prevent the Anchor from moving.

-MC-

Display Bit-accurate waveform data at high magnification levels (only) for analysis and removal of glitches, clicks and pops in a recording.

In the sample editor use the Zoom Tool to draw around the problem area and repeat to achieve the required resolution. Below is a a screen shot of the left channel on maximum Horizontal and Vertical Zoom levels, as indicated by the meters in the bottom right corner. Notice how the waveform data is smooth.

To display the data as Sample Bits:  Choose View > Show as Sample & Hold.

(If your Zoom resolution is not high enough, this option will be grayed out)

Here you can see the resulting Sample Bit display of the waveform above.

Editing with the Pencil Tool is now far easier and your edits will be sample accurate.

-MC-