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Zplane Vielklang 2

Pitch-correction & Harmony-generation Software [Mac OS & Windows] By John Walden
Published July 2014

The latest version of Zplane's Vielklang will not only generate harmonies from your vocals, but put them in tune first!

Hooks: we all want them, and pretty much every hit song has them. And, unless that song is a specialist instrumental dance track or novelty Christmas tune, the odds are pretty short that its biggest hooks will come from some killer vocals. If you need a little help in that department, there are plenty of vocal processing options available and, in the main, these come with some combination of three intentions: to improve the vocal sound, to improve vocal pitch and to generate harmony parts.

In the last of these processing niches, Zplane's Vielklang Instant Harmony 2 — VK2 for short — is the latest contender to step up to the mic. Dave Stewart was suitably impressed with the harmony-generation skills of VK1 when he reviewed the original release back in December 2008 (/sos/dec08/articles/vielklang.htm), and the new version 2 represents a significant update.

Parallel Lines

Like the original version of Vielklang, and some other market-leading tools such as Celemony's Melodyne, VK2 is not a real-time processor; you have to load your audio into VK2, let the software process it (which doesn't take long) and then audition the results. As a consequence, this is a program for studio use rather than live performance. However, this offline approach means no compromises in terms of the processing power that can be brought to bear, so the end results should be as good as current algorithms can make them.

Dave's original review noted that some user input was required to get the playback of the generated harmony parts to synchronise with the host project, and that there were some limitations on the ways in which individual notes could be edited. Thankfully, VK2 brings considerable improvements in both areas, and there are also other significant changes too. First, as well as performing harmony generation, VK2 is now also a full-on pitch-correction tool, offering a level of control that is, on paper at least, very impressive. Second, VK2 retails at about half the price of the original version. For recording musicians who are not made of money (that's most of us, then), this is bound to make VK2 a more attractive proposition.

Download (83MB) and installation of VK2 proved unproblematic, while authorisation of the software simply requires an unlock code obtained when registering. The plug-in is available for both Windows and Mac OS X, with RTAS, VST (32/64) and AU (32/64) versions available.


I did the bulk of my own testing via Cubase 7.5 running under OS X. In this context, rather than being placed as an insert effect on the audio track to be pitch-corrected and/or harmonised, VK2 is loaded as a VST Instrument. This makes sense, as it allows the plug-in to accept MIDI data both to trigger playback and also to create chords or notes to form the basis of the harmonies. Before any processing can be done, you have to import the required audio into VK2. This can be done from the plug-in's File menu option or by drag-and-drop, which worked fine from within Cubase. Stereo audio files are supported, but the material needs to be monophonic.

Once imported, VK2 performs its initial analysis and prompts the user to confirm the key, scale and tempo. During my own testing, I never had any reason to question VK2's suggestions, so there is clearly plenty of musical intelligence working away in the background here. The audio then appears in a fashion that's familiar from most pitch-correction software as waveform 'blobs' on a piano-key-style pitch grid, with a more detailed pitch curve shown in white through the various blobs. In addition, VK2 places a series of chord selections at the top of the timeline strip that it believes reflect the key/scale/melody in the most sensible musical fashion. You can edit these chords in a number of ways if required.

When you first bring audio into VK2, it analyses the pitch data to identify the key and scale used.The restyled interface in VK2 adds Arranger and Hybrid tabs alongside the piano-roll display. The Hybrid view offers the same pitch-editing tools as the piano-roll view but does it via a notation-based display rather than a piano roll. In the Arranger view, you can see the audio clip placed on a bar-grid timeline. If you need to reposition the clip — for example, to correct for any timing differences between VK2 and the host — you can do so here. However, as the drag-and-drop process placed audio into VK2 exactly at the position of the Cubase timeline cursor, I never needed to resort to this. In addition, you can add multiple clips to VK2's timeline (as long as they don't overlap, in which case the new clip replaces the old one). If my experience with VK2 in Cubase 7.5 is typical, ensuring sync between host and plug-in seems to be very straightforward — more so than in the original.

Perfectly Correct?

As mentioned earlier, while VK1 did allow some modifications of pitch to be made, perhaps the most significant addition to VK2 is that it now performs pitch correction as well as harmony generation. The bottom strip of the display contains four tabs labelled Mixer, Voice Control, Harmony Settings and Snapshots, and pitch correction is set up using the Voice Control tab. The Tune and Drift parameters influence how hard the pitch correction is applied and how much variation in pitch is allowed within a note. You can keep it natural or push it into classic 'pitch-correction effect' territory if you wish. The Timing control applies a little pull or push quantising. Finally, the Shape control allows you to shift the vocal formants up or down. This sounds natural in small amounts but, at extremes, you can also do Barry White or Mickey Mouse; the choice is yours.

For more hands-on pitch correction, editing can be done in either of two modes: Simple Edit (the default) and Advanced Edit. In Simple Mode, you get four editing options depending upon where you place the mouse pointer over a blob (or blobs — edits can be applied to multiple notes once they are selected). Notes can be moved vertically to change their pitch and shifted in time along the timeline, while grabbing them at the ends lets you adjust the start or end position, thus changing the length of the note. With any of these last three operations, adjacent notes are automatically adjusted also to ensure there are no overlapping notes. If you hold the Alt key while dragging, this behaviour is modified and adjacent notes can become detached, although they are still not allowed to overlap. Holding Alt while adjusting the pitch overrides the automatic lock to the nearest semitone for finer pitch control.

VK2 now features sophisticated pitch-correction features.The toolbar section located at the top right of the VK2 window contains buttons to engage both Advanced Edit mode and additional elements within that for editing vibrato and tremolo. You can adjust the pitch variation within a note (drift) and the steepness of the pitch curve at the start and end of a note. You can also alter the volume of a note, apply a fade-in/fade-out and change its formant shift.

If you use the Advanced-mode controls to remove the note drift, and thereby remove any natural vibrato, the vibrato/tremolo option allows you to add artificial vibrato, specify the start/end points of the vibrato, specify the vibrato amplitude at the start and finish point (so it varies with time) and add an element of tremolo that synchronises with the vibrato. I'd hesitate to say that VK2's pitch correction was in quite the same class as that of Melodyne — and, of course, it only works for monophonic performances — but it is undoubtedly very good indeed.

Usefully, the VK2 interface includes both undo and redo buttons, so you can unpick your edits one step at a time if needs be. However, I couldn't find an option to reset individual notes, which would scrap any edits you had made for the selected note(s) and start again. Unless I've just missed something here, this would be a very useful addition.

Parting Shots

Once you've chosen the appropriate blobs, hitting the Harmonize button will, by default, generate a three-part harmony consisting of your lead vocal plus two harmony parts. This works very much as described by Dave Stewart in his December 2008 review; it's 'intelligent', basing its results on the key/scale/chord combinations the algorithm has detected from the main vocal rather than simply paralleling the pitch changes in the lead, and produces very 'human' musical harmonies. You can hit Harmonize repeatedly, making different selections each time, and the new selections are added to the existing harmonies.

Advanced-mode pitch editing provides detailed control of pitch, pitch drift, amplitude, formants and vibrato on a per-note basis.The Harmony Settings tab at the base of the screen allows you to customise the number of voices and the style of harmony. There are plenty of options to experiment with, catering for a wide range of musical styles. Each voice is colour-coded in the display, with the original voice appearing orange; the rightmost panel of the Harmony Settings tab allows you to reposition the orange lead vocal relative to the other voices, controlling whether the harmonies are above or below the lead and their pitch spread relative to the lead. The level of control is very good indeed and, once you have the required harmonies, flipping to the Mixer tab allows you to set their individual levels and pan positions. Rather wonderfully, all the pitch-correction tools described above can be applied to each of the harmony voices also.

Stretching The Boundaries

In use within my Cubase host, I have to say I was very impressed with the pitch correction offered by VK2 and the level of editing detail it provides. It perhaps doesn't make audio quite as elastic as Melodyne, but it is a broadly similar experience and the results are very good indeed. Equally, the process of generating harmony parts is both efficient and creative. While a little music knowledge can help in narrowing down the choices you might explore, almost anyone could conjure some suitable harmony vocal parts with a bit of experimentation. And, in terms of the audio quality that can be achieved, providing your original lead vocal provides a clean starting point, the results can be very convincing.

My only negative comments would relate to a coupleThe Snapshots feature provides an excellent means of auditioning different harmony settings and, via MIDI, can also be used to trigger the snapshots in real time. of gremlins I experienced. First, within Cubase, the plug-in's outer frame disappeared on a regular basis and I had to close the window and then reopen it to get it back. More drastically, but thankfully less often, VK2 did cause my generally rock-solid Cubase system to go belly up on two occasions. I recovered fine with no loss of work, but obviously this is not ideal. Hopefully, these issues will be dealt with promptly through minor updates.


I'm thoroughly impressed with VK2. The occasional glitch aside, it did its job with a minimum of fuss. The graphical changes and the workflow improvements make for a slicker experience, and the addition of comprehensive pitch correction is a significant plus. It really is very well implemented, and the fact that these pitch tools can also be applied to the vocal harmony parts is very useful.

As with the first version, VK2 makes the creation of automated vocal harmonies rather too easy for comfort. What's more, it does it in a musically intelligent fashion while still offering the user control over the process should they need it. And providing you start with a well-recorded lead vocal part, the quality of the harmonies generated will sit very comfortably within a mix, without their 'fake' nature becoming too obvious.

It is worth emphasising the price, too: at just over £100, Vielklang Instant Harmony 2 represents very good value for money. There is a 'lite' LE version available, which doesn't include features such as the Advanced Edit mode for pitch correction, the Snapshot system or MIDI input harmonisation, but given the modest price of the full version, I'd suggest it's worth making the stretch. If you are looking for some serious pitch correction and vocal harmony generation but don't have the budget to reach for some of the established competition, you really should download the trial version of VK2 and road-test it on your own system. For what is obviously a niche application, this is a lot of software for a very modest price.  


There are a number of possible alternatives to VK2 but nothing that matches the exact combination of harmony generation, pitch correction and price. For example, Antares' Harmony Engine EVO also provides intelligent automatic four-part harmonies. While it doesn't offer the same level of pitch correction (you need Auto-Tune for that), it works in real time, and perhaps packs in more options than VK2 in terms of harmony control, but it also packs a bigger price. For an 'all-in-one' vocal processing suite, including pitch correction and harmony generation, there is also iZotope's excellent Nectar 2 Production Suite. Of course, if you are happy to hand-craft the occasional harmony line but want some absolute audio magic in terms of pitch manipulation, then Celemony's Melodyne Editor is the choice; not cheap but jaw-droppingly brilliant.

Mindful Of MIDI

As mentioned in the main text, Vielklang Instant Harmony 2 behaves in some ways like a virtual instrument rather than an audio effect and, as such, it can employ incoming MIDI data in several ways. First, many of the parameters can, if required, be automated. In addition, if you don't approve of one of the chords VK2 has chosen, you can simply place the timeline cursor over that chord and then play your preferred choice using a MIDI keyboard. The display, and any harmonies generated, will update to match.

One further neat feature of the plug-in is Snapshots. In the Snapshots tab, you can create a series of snapshots based upon the current settings and harmonies. These snapshots can be assigned to MIDI notes on the virtual keyboard and, if you engage MIDI trigger mode using the MIDI icon located at top right, you can switch between snapshots from a MIDI keyboard. These triggers are made in real time so, in this mode, sync to your project is controlled by the timing of the trigger note.

Finally, you can select the MIDI harmony mode and play chords in as playback is under way. VK2 will generate harmonies based upon your MIDI input. This works but, because of the processing going on, I'm not sure it is the smoothest experience VK2 offers.


  • Excellent pitch-correction tools now included.
  • Super-simple auto-harmony generation.
  • Great value for money.


  • Occasional gremlins during testing.
  • No 'reset note' option.
  • At this price, nothing else!


Zplane's Vielklang Instant Harmony 2 has added seriously good pitch correction to its existing and impressive auto-harmony generation. It represents very good value for money.


£106.28; LE version £70.56. Prices include VAT.

$149; LE version $99.

Test Spec

  • Vielklang Instant Harmony 2.0.12 (build 720).
  • Apple iMac with 3.5GHz Intel Core i7 CPU, 32GB RAM and Focusrite Scarlett 8i6 interface, running Mac OS 10.9.2.
  • Tested with Steinberg Cubase 7.5.20.