Vocal Tune Studio AUv3 and Standalone User Manual

Introduction and instructions

Vocal Tune Studio Time only mode allows you to set anchor/stretch points and then time stretch those specific parts of your audio without changing their pitch.

Unlike Pitch and Time mode which can only be used for monophonic (one note at a time) sound sources and preferably a monophonic audio recording (one audio channel only), Time only mode can be used with any audio file (please note, though, that the screenshots below show a monophonic audio clip loaded - if a stereo clip were loaded, the waveforms of both the left and right channels would be represented in the display).

NOTE. Real time time stretching like this is a very CPU intensive task and, for that reason and because of the enormous number of varied devices Vocal Tune Studio needs to be able to run on, the time stretching factor in Vocal Tune Studio has been limited to between 0.33x and 3.0x of the original duration. This should be adequate for most needs but, if not, a possible workaround could be to apply the maximum/minimum stretching limit, render the clip to audio file and then reload that rendered audio to open in Vocal Tune Studio again where the required part could be stretched within the limits again. The current stretch factor used for each section to the right of an anchor/stretch point is displayed next to the anchor/stretch points at the top of the display.

When you launch Vocal Tune Studio Standalone/AUv3 you will first see the following dialog (unless you have Always start in Pitch and Time correction mode selected in the Options available via the Three Dot Button - if so, open Vocal Tune Studio in Pitch and Time mode and deselect that option before opening the app or plug-in again).

This allows you to select which mode Vocal Tune Studio will open your audio in. Select Time correction only and tap Ok.

If this is the first time you have opened Vocal Tune Studio in Time correction only mode you will be shown a brief First Time Use Quick Help text to introduce the mode and its functionality. It is recommended that you take the time to read this text.

As with Pitch and Time correction mode, Vocal Tune Studio Time correction only mode will initially be empty and you will be required to capture or import your audio into it. The process for doing this is the same as with Pitch and Time correction mode.

In standalone mode, you can press the Record button and record audio live using the device microphone or connected audio device. You can also import audio files and paste audio from the iOS clipboard (if present) via the Three Dot Button options.

In AUv3 plug-in mode, load Vocal Tune Studio as an insert effect on an audio track or channel containing an audio clip in your host app and follow the instructions described here, and specifically for popular AUv3 host apps here, to capture audio into Time correction only mode by pressing Record in the Vocal Tune Studio AUv3 plug-in and Play (not Record) in the host app. Stop audio capture by pressing Record again in Vocal Tune Studio.

NOTE. Though it is possible to directly import audio into the AUv3 plug-in version of Vocal Tune Studio, it is not recommended that you do so for the reasons detailed here. It is advised to capture/record audio present on the host track into Vocal Tune Studio AUv3 as stated above to ensure there is a proper relationship between the host app and the plug-in.

The screenshot below shows the clip used in the tutorial later imported into Vocal Tune Studio Standalone in Time only mode. As you can see, the audio waveform is shown in light gray across the center of the timeline display. A full guide to the user interface can be found here.

NOTE. Since this is the clip used in the tutorial opened in standalone mode, you will notice if you look carefully at the screenshot below that the bar lines are placed at different points from the way they are seen in the tutorial screenshots. This is because standalone mode doesn't allow you to enter a time signature. The tutorial recording is of a piece in 3/4 time but in standalone mode it is shown on a grid with bar lines representing 4/4 time (though ,functionally, this makes no difference to the end result). The screenshots for the tutorial, however, show the Vocal Tune Studio AUv3 plug-in, where the  plug-in displays the time signature and tempo as set in the host application and therefore the bar lines are in the correct position for the piece's 3/4 time. 

The key to using Vocal Tune Studio's Time only mode is the placement of anchor/stretch points. Anchors and stretch points are essentially the same thing, the difference being that the stretch point is between two anchor points and can therefore be used to initiate a stretch from that point whilst the overall stretching is constrained between the anchor points. Add another anchor beyond one of the two existing anchors and the original anchor point closest to it can then be used as a stretch point itself, using the original stretch point as its anchor on the other side. As such, these markers can be simultaneously anchors and stretch points depending on whether they exist between two other anchors/stretch points or not and how they are then interacted with. 

Anchor placement in Time only mode is the same as the Pitch and Time mode's 'None' option for auto placement (except there are no notes to be snapped to). As such, all anchor/stretch points must be manually created by the user by double tapping at the desired position within the waveform display area. This being the case, it is especially important to remember to place anchors on either side of your desired stretch point to ensure that you only time stretch the part of your audio you want to rather than stretching everything using the start and end of the clip as de facto anchor points (unless that's what you want to do). Remember that the Undo option is always there if you place an anchor/stretch point in the wrong place, that you can double tap on existing anchor/stretch points to remove them and there is also the Remove all stretch points option available via the Three Dot Button should you want to reset and start again. The Remove time correction option, also available via the Three Dot Button, will remove all effects of Vocal Tune Studio Time only mode from your audio.

The screenshot above shows the audio clip opened in Time only mode but has yet to have any anchor/stretch points placed to be used for time stretching. Let's resize the display by pinch/pulling with two fingers to zoom into part of the audio present and place some anchor/stretch points.

Anchor/stretch points are placed by double tapping at the points at which you want them to be created. Zooming into your audio gives you much more control of this process. If you place one in the wrong place, simply use the Undo button immediately or double tap on it again at any time to remove it.

Anchor/stretch points are represented by triangular orange markers at the top and bottom of the waveform display area with a dotted yellow line running between them to indicate their position throughout the display.

In the screenshot above, three anchor/stretch points have been placed. Number 1 at the beginning of a section of audio represented in light gray; number 2 at the end of that section of audio and number 3 at the beginning of the next peak in the audio waveform. 

As mentioned above, anchors and stretch points are essentially the same thing, the difference being that the stretch point is between two anchor points and can therefore be used to initiate a stretch from that point whilst the overall stretching is constrained between the two anchor points. A such, in the screenshot above, you can see how - 

Number 1 is an anchor for number 2.

Number 1 is a stretch point using the beginning of the audio clip and number 2 as anchors.

Number 2 is an anchor for numbers 1 and 3.

Number 2 is a stretch point using numbers 1 and 3 as anchors.

Number 3 is an anchor for number 2.

Number 3 is a stretch point using number 2 and the end of the audio clip as anchors.

After you have placed some anchor/stretch points you can begin to time stretch your audio as seen in the next screenshot.

To use a stretch point, simply long press on it until its dotted vertical line becomes a solid orange line and continue to hold as you slide left or right to shrink/stretch the audio between the anchor points from the position of the stretch point. 

In the screenshot above, anchor/stretch point number 2 has been slid to the left, shortening the duration of the audio between 1 and 2 and increasing the duration of the very quiet section of audio between 2 and 3.

At this point it is worth reiterating the note above. Real time time stretching is a very CPU intensive process so the stretch factor in Vocal Tune Studio is limited to between 0.33x and 3.0x the original duration. The current stretch factor used for each section to the right of an anchor/stretch point is displayed next to the anchor/stretch points at the top of the display.

The result of sliding anchor/stretch point number 2 to the right can be seen below.

In the screenshot above, anchor/stretch point number 2 has been long pressed until its vertical line has become a solid orange line and, whilst continuing to hold, slid to the right. This has increased the duration of the audio between anchor/stretch points 1 and 2 and shortened the duration of the very quiet audio between 2 and 3.

You can add as many anchor/stretch points and apply as many stretches as as you require to achieve your goals within your audio clip. Remember you can remove individual anchor/stretch points by immediately using the Undo function or by double tapping on them again. As stated above, you can reset your audio and remove all anchors without leaving Vocal Tune Studio using the Remove all stretch points option available via the Three Dot Button . This option cannot be undone so please use with caution.