When I received my review copy of the fourth edition of Synchro Arts Revoice Pro I must confess I thought I’d be testing a straightforward vocal tuning application. Instead what I found was a hub of time and pitch manipulation for both spoken and sung vocal recordings… along with any other monophonic instrumental sources you choose to throw at it.

In the broadest terms, Revoice Pro is an editing and processing multi-track program in which mono and stereo audio tracks are either processed (Dub and Warp tracks), act as analytical sources for control parameters (Guides), or are output as the product of one of these processes. Many tracks will end up being used for dual functions, with some producing new tracks that then act as guides or dubs for another generation of outputs. Alternate audio segments can even be archived in playlists of up to four layers to allow further experimentation. Things can get pretty complicated, if you let them.

STANDING ALONE

PreSonus Studio One, Logic Pro X 10.4 and now Cubase 10 users presently have the joy of using the integrated ARA 2 (Audio Random Access) plug-in version of Revoice Pro. The rest will simply experience it as a standalone application. On occasion you may run Revoice on its own during an editing session, but in musical applications it’s more common to run it synchronised alongside your preferred DAW.

In standalone mode, Add audio file and Export modes perform as you would expect, along with the ability to save Revoice sessions with associated files. This is particularly convenient for later tweaks. In my case, I used the Revoice Pro Link and Pro Monitor plug-ins to transfer audio from my DAW into the multi-track layout of Revoice, then back again. While not quite automatic, configuring this connection was straightforward and worked as expected.

Once a link is enabled, Revoice slaves its playback to the transport of the linked DAW, with a mix of all active tracks fed back to an auxiliary return channel in your main project. Despite the smooth setup I must confess to finding it tedious constantly switching between application windows. Of particular frustration was my instinctive use of the spacebar to stop the track while the Revoice window was in focus. On these frequent occasions the Revoice transport stopped while the rest of the project continued. A dual monitor setup may have helped but a mapped MIDI transport would have been ideal.

If you’re prone to combining dense vocal arrangements with a desire for constant edit-ability, it’s worth noting that you’ll soon find yourself with two parallel mixes, running in synced applications. For those of us who fall short of the Chess grandmaster mind state, I’d recommend muting processed channels in Revoice, for necessary revisits, while dragging/exporting files back into your DAW track playlists. You’ll, of course, need to name your Revoice tracks accordingly to keep everything in order.

A SHIFT IN FOCUS

If your idea of musical nirvana is a bluegrass quartet huddled around a single microphone then I may have lost you at ‘Hello’, but I think Revoice Pro 4 offers some musical options that should appeal to even the most traditional of recordists. Its function revolves around three primary ‘Processes’, launched for configuration by a quick press of B on your keyboard. As an aside here, fluent use of Revoice demands an engagement with its keyboard shortcuts; you simply won’t develop a smooth workflow without them. Once you’ve added/transported audio into your tracks you begin by selecting either the Audio Performance Transfer (APT), Double or Warp process and configuring the desired source and output tracks. What follows is a further settings dialogue for that specific processing instance. These settings configure either the algorithms used to analyse the pitch and timing of audio, in the case of Warp, or define the processing settings for APT and Double. All can be opened and tweaked at any time. Preset settings can be saved for different applications and shared with other users. While the factory settings were a good starting point, I preferred to refine and store my own settings.

In the case of Warp particularly, much of the manual editing workload is defined by how well the algorithm analyses your audio, so it’s worth understanding how these settings are applied. Many of these adjustments result in immediate process updates and in a few cases a resultant lag in fader response was produced on all test systems. While this was described by the incredibly attentive support staff as a known trade off rather than a bug, I think it warrants further attention.

The Warp process is where all of your manually applied vocal tuning will be managed. It allows for shifts in both pitch and timing, time stretching and compression, the exclusion of silence, spill and sibilant moments from processing — elements that often produce artefacts in automated processes — and more nuanced adjustment of pitch expression through note transitions, note range and tilt, and the management of vibrato regions; maintaining a singer’s natural pitch modulation in stretched audio.

As a long term user of the more basic Melodyne packages I thought Warp sounded great. I did experience a significant learning curve though, and the necessity of shortcuts and key modifiers didn’t ease this transition. There’s no question that it’s these pitch and time correction processes that will most benefit from ARA 2 plug-in implementation within a wider selection of DAWs. Notwithstanding, for those who’ve only used blunt force automatic vocal tuning options I sincerely endorse the more refined control afforded by Revoice Pro. The ability to manipulate and even redraw the curves of note transitions is at times a revelation and reminds you that often what we value is not necessarily perfect pitch, but rather increased control.

Back in the day, VocAlign was bundled by Digidesign in its DV Toolkit option. It was my first exposure to SynchroArts, which had another massive hit in the post world called Titan (for syncing up location sound after the picture had been cut). Vocalign was pretty good at syncing a dub take to an original take, adjusting syllables and transients to match timing between performances. Revoice Pro takes that concept to a whole new level, matching not just timing, but also pitch and inflection, vibrato and emphasis. It promises a lot!

PLUG-INS LEAVING THE NEST

One of the hurdles I face with software like iZotope RX4 and Revoice Pro 3 is that in my mind they started life as plug-ins inside my favourite DAW and now they’re all grown up and want to be applications, linked to my DAW. They are forcing me to change the way I work. In the case of RX4 I haven’t looked back. On OS X, switching apps with ‘spaces’ and having RX’s output monitored through my PT HD hardware via a plug-in has proven to be a much faster way to work. I was expecting a similar experience with Revoice Pro, but instead found that its monitor plug-in not only piped audio into my HD session but also linked the transport between the apps — a bit like Rewire.

I can see how for many users this may be a benefit, but in my case, being used to a similar but slightly different workflow I found it maddening. I’d fix my clip in Revoice Pro, audition sync in Revoice Pro, and then spot it into my Pro Tools session to hit play and find two versions playing back simultaneously; the version in my mix running through my dialogue plug-in chain, alongside the fixed, but raw, take playing back from Revoice Pro. Revoice Pro’s work had been done, and it was just a distraction by that point. A simple fix was to key a gate off my output, so when transport in PT was engaged, it muted the Revoice Pro monitor return, but it would be nice if this workflow was enabled by a preference or tick box in Revoice Pro.

TARGETED WORKFLOW

Revoice Pro is supported by all the main Mac and PC DAWs, but I was using it with Pro Tools HD, so I’ll be referring to that workflow. With the Revoice Pro app open and the monitor plug-in inserted on an aux, you can now find an audio region to fix, select it and open the Revoice Pro Connect Audiosuite plug-in. The ‘Send’ button transports the audio to a chosen track inside the Revoice Pro application.

You can have multiple tracks inside Revoice Pro because you often need to compare two or more pieces of audio; like your source and a target track to time align it to, for instance. If you’re processing backing vocals you may want to work with a whole stack of tracks inside Revoice Pro. So, when sending audio from your host DAW, you need to assign it to an appropriate track in Revoice Pro from the pull down in the Audiosuite plug-in. Once your source and target audio are in Revoice Pro, the fun starts!