Steinberg Wavelab Elements 8 Manual

							Loops
About Refining Loops
271
If the automatic search for loop points is not successful, you can 
process the waveform to allow for smoother loops by crossfading areas 
of the waveform close to the loop start and end points.
To use the Loop Tweaker, you must first define a loop using a pair of 
loop markers.
Loop Points Adjustment Tab
Use the Loop Points Adjustments tab in the Loop Tweaker dialog to 
manually refine a loop selection by dragging on the waveform left/right 
or by using the automatic search buttons to find the nearest good loop 
point. The aim is to align the waveforms so that they meet at a 
zero-crossing point where the waveforms match as closely as possible. 
When you adjust your loop start and end points within the dialog, the 
start and end loop markers in the main waveform window adjust 
accordingly. Note that this movement may or may not be visible 
depending on how much you move the markers and on the zoom factor 
that you have selected.
It may be helpful to loop the transport during playback so that you can 
hear the difference when you adjust the loop markers within the dialog. 
Note that if you are not using a crossfade or post-crossfade, you do not 
need to click Apply when tweaking loop points. You can also leave this 
dialog window open and manually adjust the position of the markers in 
the main waveform windows.
Crossfade Tab
This tab allows you to apply a crossfade of the end of a loop with a copy 
of the beginning of the loop. This can be useful to smooth the transition 
between the end of a loop and its beginning, especially when you use 
material that does not naturally loop. Use the envelope drag points or 
value sliders to adjust the crossfade envelope. Click Apply to process 
the crossfade.
Post-Crossfade Tab
This tab allows you to cross fade the loop back into the audio behind the 
end of the loop by mixing a copy of the loop back into the audio. Use the 
envelope drag points or value sliders to adjust the crossfade envelope. 
Click Apply to process the post crossfade. 
						

							Loops
About Refining Loops
272
Refining Loops
You can refine loops using the Loop Tweaker tool.
PREREQUISITE 
Set up a basic loop.
PROCEDURE
1. In the Audio Files workspace, select the loop that you want to 
refine by clicking between its loop start and loop end marker.
2. Select Process > Loop Tweaker.
3. Refine your loop using the settings in the Loop Tweaker tool.
4. Click Apply.
Moving Loop Points Manually
If your loop still has glitches or bumps at the turning points, you can use 
the Loop Tweaker tool to move the points in small steps to remove the 
glitch.
This is similar to moving the loop points in the wave display, but with a 
visual feedback to facilitate finding good loop points.
There are two ways of moving the loop points manually on the Loop 
points adjustment tab in the Loop Tweaker dialog:
• Drag the waveform to the left and right.
• Use the green arrows below the waveform to nudge the audio to 
the left and right. Each click moves the loop point by a single 
sample.
The following applies when moving the loop points manually:
• To move the end point to a later or earlier position, move the left 
part of the display.
• To move the start point to a later or earlier position, move the right 
part of the display.
• To move the start and end points simultaneously, activate Link 
start and end points. This way, when adjusting a loop point, the 
length of the loop stays the same, but the entire loop is moved.
• You can also adjust the loop markers in the wave window. 
						

							Loops
About Refining Loops
273
Automatically Detect Good Loop Points
The Loop Tweaker tool can automatically search for good loop points.
PROCEDURE
1.In the Audio Files workspace, select the loop that you want to 
refine by clicking between its loop start and loop end marker.
2. Select Process > Loop Tweaker.
3. On the Loop points adjustment tab, make sure that Link start 
and end points is deactivated.
4. In the Automatic search section, specify the Aimed 
correspondence and the Search accuracy.
5. Click the yellow arrow buttons to start the automatic search for a 
good loop point.
WaveLab Elements scans from the current point forwards or backwards, 
until it finds a point that matches. You can stop at any time by clicking the 
right mouse button. The program then jumps back to the best found 
match.
6. Check the loop by playing it back.
7. Optional: If you think there might be a better loop point, continue 
with the search.
Temporarily Storing Loop Points
Temporarily saving and restoring loop points allows you to quickly 
compare different loop settings.
PREREQUISITE 
Set up a basic loop and open the Loop Tweaker tool.
NOTE
There are five slots for temporarily saving loop point settings per wave 
window and montage window, not one per set of loop points. This 
means that if you have several sets of loops in your file, you must be 
careful to not recall the wrong set.
NOTE
Only loop positions are temporarily saved. 
						

							Loops
About Refining Loops
274
PROCEDURE
1. On the Loop points adjustment tab, in the Temporary 
memories section, select M.
2. Select one of the five memory slots.
About Crossfades in Loops
Crossfading is useful to smooth the transition between the end of a loop 
and its beginning, especially when using material that does not naturally 
loop.
Sometimes it is impossible to find a loop that does not cause any 
glitches. This is especially true for stereo material, where you might be 
able to find a perfect candidate for only one channel.
In this case crossfading smears the material around the end loop point 
so that it loops perfectly. This is achieved by mixing material from before 
the loop start with material that is located before the loop end.
Note that this technique alters the waveform and therefore changes the 
sound. However, normally you can find settings that minimize this 
problem.
Creating a Crossfade
PROCEDURE
1.In the Audio Files workspace, create a good a loop as you can.
2. Select Process > Loop Tweaker.
3. Decide if you want to create a crossfade or a post-crossfade:
• If you want to create a crossfade, click the Crossfade tab.
• If you want to create a post-crossfade, click the Post-Crossfade 
tab.
4. Make sure that Crossfade audio at end of loop with audio 
before loop (Crossfade tab) or Crossfade audio after loop with 
audio of loop start (Post-Crossfade tab) is activated.
5. Decide on a length for the crossfade either by dragging the length 
handle or by adjusting the Length value below the graph.
6. Decide on a crossfade shape by dragging the shape handle or by 
adjusting the Shape (from equal gain to equal power) value. 
						

							Loops
About Refining Loops
275
7. Click Apply.
The sound is processed. Each time that you click Apply, the previous 
loop process is automatically undone. This allows you to try out many 
settings quickly.
NOTE
Do not move the loop points after you have performed a crossfade. The 
waveform has been processed specifically for the current loop settings.
AFTER COMPLETING THIS TASK: 
• You can check the crossfade visually by opening the Loop points 
adjustment tab and activating Display processed audio. When 
this is activated, the display shows a preview of the crossfaded 
waveform. When the option is deactivated, the display shows the 
waveform original. Switching back and forth allows you to compare 
the two.
About Post-Crossfades
Post-crossfading means crossfading the loop back into the audio after 
the end of the loop so that there is not glitch when playback continues 
after the loop. This is done by mixing a copy of the loop back into the 
audio.
The post-crossfade can be set up on the Post-Crossfade tab of the 
Loop Tweaker dialog.
The post-crossfade analyzes the part of the waveform that occurs just 
after the loop start and processes a certain area that begins at the end 
of the loop. The length parameter adjusts the size of this area. Everything 
else is identical with regular crossfading.
Loop Tweaker Dialog
This dialog allows you to adjust the loop start and end points, and 
crossfade the loop boundaries.
In the Audio Files workspace, select Process > Loop Tweaker. 
						

							Loops
About Refining Loops
276
The Loop Tweaker dialog consists of the following tabs:
Loop Points Adjustment Tab
The top of this dialog shows the beginning and the end of the waveform 
between the loop markers. The bottom of this dialog offers the following 
options:
Loop End - Green Arrows
Move the loop end points to the left/right.
Loop End - Yellow Arrows
Invokes an automatic search for the nearest good loop point to the 
left/right of the loop end point and moves the end point to that 
position.
Loop Start - Green Arrows
Moves the loop start points to the left/right.
Loop Start - Yellow Arrows
Invokes an automatic search for the nearest good loop point to the 
left/right of the loop start point, and moves the start point to that 
position.
Stereo merge
If this option is activated for a stereo file, the two waveforms are 
overlayed, otherwise they are shown in two separate sections. 
						

							Loops
About Refining Loops
277
Overlap
If this option is activated, the waveforms of both halves are 
continued in the other half. This shows how the waveform looks like 
right before and after the loop.
Display processed audio
If this option is activated, the display shows a preview of the 
waveform after crossfading. If deactivated, you see what the 
waveform looks like without crossfading. This option only makes 
sense after you have set up a crossfade and clicked Apply.
Automatic vertical zooming
If this option is activated, the vertical magnification is adjusted so 
that the waveform always fills the entire display vertically.
Zoom
Sets the zoom factor.
Current correspondence
Indicates how well the waveforms near the loop points match one 
another. The left value estimates the similarity across several wave 
cycles, while the right value estimates the similarity of the few 
samples near the loop points. The higher the values, the better the 
match.
Aimed correspondence (0-1000)
Sets up the automatic search for good loop points. This defines 
how well the found section must resemble the section to which it 
is compared, in order to be considered a match. The higher the 
value, the more precise the resemblance must be. A value of 1000 
most likely fails, since it requires a 100
 % perfect match.
Search accuracy
Determines how many samples should be taken into account by 
the auto-find analysis. Higher values result in greater accuracy, but 
also in longer processing times.
Link start and end points
If this option is activated, both the start and end points move 
simultaneously when you adjust the loop points manually. That is, 
the loop length is exactly the same, but the entire loop moves.
Temporary memories
Allows you to save up to five different sets of loop points which you 
can later recall. This allows you to try out several different loop 
settings. To store a set, click this button, then on one of the buttons 
1-5. 
						

							Loops
About Refining Loops
278
Crossfade Tab
Crossfade audio at end of loop with audio before loop
To enable crossfading, activate this checkbox. The crossfade is 
applied when you click Apply.
Length
Determines the section length of the audio file to be used in the 
crossfade. Generally, you want the crossfade to be as short as 
possible, with an acceptable result:
• Using a long crossfade smoothens the loop. However, more of the 
waveform is processed, which changes its character.
• A shorter crossfade affects the sound less, but the loop is not as 
smooth.
Shape (from equal gain to equal power)
Determines the shape of the crossfade. Generally, use low values 
for simple sounds and high values for complex sounds. 
						

							Loops
About Refining Loops
279
Post-Crossfade Tab
Crossfade audio after loop with audio of loop
To enable crossfading, activate this checkbox. The crossfade is 
applied when you click Apply.
Length
Determines the section length of the audio file to be used in the 
crossfade. Generally, you want the post-crossfade to be as short 
as possible, with an acceptable result:
• Using a long post-crossfade smoothens the loop. However, more 
of the waveform is processed, which changes its character.
• A shorter post-crossfade affects the sound less, but the loop is not 
as smooth.
Shape (from equal gain to equal power)
Determines the shape of the post-crossfade. Generally, use low 
values for simple sounds and high values for complex sounds. 
						

							Loops
About Looping Seemingly Unloopable Audio
280
About Looping Seemingly Unloopable 
Audio
Sounds that constantly decay in level or continuously change in timbre 
are difficult to loop. The Loop Tone Uniformizer allows you to create 
loops from sounds that seem unloopable.
The Loop Tone Uniformizer applies processing to the sound that 
evens out changes in level and timbral characteristics in order for a 
sound to loop properly. For example, this is useful for creating looped 
samples for a softsynth or hardware sampler.
The Loop Tone Uniformizer includes a crossfade facility so that the 
original sound fades into the processed sections as playback 
approaches the loop start.
To use the Loop Tone Uniformizer, you must have a loop defined using 
a pair of loop markers. The original length of the loop is not changed.
Looping Seemingly Unloopable Audio
PROCEDURE
1.In the Audio Files workspace, set up a basic loop.
2. Select Process > Loop Tone Uniformizer.
3. Make sure that either Slice mixing or Chorus smoothing is 
activated and make the settings.
4. Optional: Open the Pre-Crossfade tab, and set up a crossfade.
5. Click Apply.
The sound is processed. Each time that you click Apply, the previous 
loop process is automatically undone. This allows you to try out many 
settings quickly.
NOTE
Do not move the loop points after you have performed a crossfade. The 
waveform has been processed specifically for the current loop settings.
AFTER COMPLETING THIS TASK: 
After using the Loop Tone Uniformizer, the transition from the end of 
the loop to the end of the file is in many cases not very natural. This can 
be fixed by creating a post-crossfade using the Loop tweaker.