Source-destination Editing With ReaClassical

Here’s ReaClassical in a simple horizontal‑workflow guise. Just three tracks, and three takes of the same material. On the right an ‘assembly line edit’ is being put together using the best moments from the takes: note the specialised Source and Dest (Destination) markers in the ruler.

We explore a clever set of donationware scripts that transform the popular Reaper DAW software into a source‑destination editing powerhouse.

Reaper is a DAW that’s famous for its unparalleled scope for customisation, and there’s a very active community of developers who write scripts to take advantage of that. A select few, though, take the script‑writing further than others, to turn this DAW into something quite different. One such project is ReaClassical — a set of open‑source scripts that transforms Reaper into an amazingly capable source‑destination audio editor that has specialist features to support your sessions from recording right through to mixing, mastering and album authoring. I suppose I could conceivably have written this article as a review, but it would have taken way too many pages to do it justice. Instead, I thought it might be a good idea to demonstrate some of the possibilities by taking you through a few useful examples of how and why you might want to use it.

Source‑destination Editing

So, what’s ‘source‑destination editing’, exactly? Still uncommon in audio circles, it’s a standard approach in the video world that comes into its own when dealing with mostly acoustic musical styles, where performances are played and recorded naturally rather than performed to a click track, and overdubbing isn’t typically used. Which is to say classical music, many types of folk/world music, and jazz. For such styles it’s normal, in a recording session, for the recordist/producer to gather multiple takes (the ‘source’) of the same pieces, with a view to piecing together a ‘best bits’ edit (the ‘destination’) in post‑production, cutting between takes to cover musical glitches, possibly assisted by notes made by a producer during the sessions.

It isn’t impossible to do this using Reaper in its standard form, of course, or indeed most DAW software. But for this job, a source‑destination (S‑D) system is faster and more flexible. It supports gathering material on the recording session, with really robust track and item grouping. Editing then happens on slick and fast ripple‑edit principles, so you can build edits without laborious cutting and pasting. Crossfading also plays a big part, knitting together edited material with quite different facilities from those offered by the vast majority of DAWs. In ReaClassical, keyboard shortcuts drive every aspect of this: the user is rarely required to use any modifier‑key combinations, and the shortcuts are grouped tightly and logically on your computer keyboard — all of which is intended to facilitate ease and speed of use.

This isn’t the only S‑D‑capable DAW, but virtually all of the others that are currently available are Windows‑only affairs, and they’re often quite expensive too: Sequoia, Pyramix and SADiE, for example. ReaClassical will run in macOS and various flavours of Linux, as well as Windows, and it’s donationware. Given that Reaper is also inexpensive, this makes it a much more accessible system than most.

On The Session

To use ReaClassical on a recording session, after booting up the portable Reaper install, pressing F7 is a good first step. A Horizontal Workflow dialogue box (we’ll return to that terminology) asks how many tracks are required, and the answer should equate to how many stereo or mono mic sources you’re intending to use. Hit OK, and ReaClassical creates enough track lanes, with track (and item) linking already set up. Next steps are to name the tracks (double‑click fields in the Track Control Panel in the usual way) and configure track inputs (right‑click in the nearby level meter, or use the Routing Matrix).

You can set up tracks as you please, but it’s a good practice to choose your main stereo pair of mics for the parent track, track 1: this ensures that a healthy, representative waveform is visible even when the track group is closed. When you’ve done this, press F7 again to ‘sync’ tracks and mixer channel names, and build some behind‑the‑scenes routings. Finally, save your new project.

To start recording, F9 is your friend. A first press record‑arms all your tracks. Press again to start recording, and once more to stop. You may notice immediately the way ReaClassical names your recorded media items in the track lanes: along with the track’s number and name, they’re given a ‘T’ suffix that gives them a unique ‘take’ identification. This numbering is the key to tallying up recorded material with a producer’s notes made on a session about what went well and what might need attention. ReaClassical keeps incrementing this number as you make more recording passes, and it keeps this harmonised between tracks even if you add new tracks (using the Shift+T shortcut) some way into a session.

The floating Take Number window is a wonderfully clear reference during a recording session, and Find Takes is a real time‑saver for quickly locating Source material, especially if you’ve recorded hours of it, and hundreds of takes.

Two really specialised features build on this take functionality, and they’re worth their weight in gold. The first is a current take number display: Ctrl+Return or Ctrl+Enter (Command on macOS, as always) opens it. This is a simple floating window with a nice clear number: when not recording it shows in green the number of the next take, but during recording the number of the current take, in red. It brings so much clarity to a session, especially hours in! The second feature is closely related. When not recording, pressing Return or Enter opens a Find Take dialogue box. Type in a number (and hit Enter or Return), and ReaClassical relocates the play cursor to the start of that take, reading the metadata in the audio items, with not a marker in sight.

There’s one more thing to mention here: playback, which is often required in a session to check balance, and for foldbacks for musicians. You can click the playback position in the time ruler or use Find Takes, and both work really well, but there’s another option. Hit the keyboard shortcut A (for ‘audition’), and playback will start from the mouse pointer position, when it’s placed over a track lane. Point at an item in the parent track and it plays the whole mix. Point at an item in a child track, and it effectively solos that track. Its fundamental strength is its speed: you can find musical sections simply by repeatedly pressing A as you move your mouse over one or many items. Audition is used elsewhere too, as we’ll see.

In The Edit

So far, we’ve only dealt with ‘source’ material: audio captured in the session. But the key to a source‑destination editing system is taking that and building a separate edit from it. So let’s look at that now.

For simple, shorter jobs, continuing with a ‘horizontal’ setup can work fine. Thinking about those first principles of source‑destination editing again, what we can do now is grab the best bits from our various session/source takes, and start splicing them together to form a better composite whole. A typical first step is an ‘assembly line edit’, working through a piece from start to finish. Here’s how it might go.

Using Find Takes and Audition, find a take that represents the best start to the piece of music you’ve recorded. It may go awry some way in, and that’s OK — it’s what this style of editing is all about, in fact. We want to mark just the ‘good bit’, and for this we use two specialised ReaClassical marker types: Source In and Source Out, placed with keyboard shortcuts 3 and 4, respectively. These can be placed during playback or when playback has stopped, and the markers can be dragged manually if necessary; the locations need to be roughly right, musically speaking, but needn’t be laser accurate.

Next, click in the time ruler above an empty spot in the timeline, probably after the session takes run out. Press 1. This places a Dest In marker (short for ‘destination in’), which marks the spot at which the edit will start to be built. (You should now have three points marked.) Then press F3, the shortcut for ‘Assembly Line edit’, to copy the marked source region to the destination marker location — without the several extra steps involved in a traditional select, copy, paste process. What’s more, the Dest In marker automatically moves along, so it’s perfectly placed to receive the next source material.

It’s now a case of working through the music, choosing good sections within takes and marking them with 3 and 4, each time pressing F3 to add to the rough edit. You might have to do this a few times or a few dozen, depending on the length of the music and how good the performance was, and potentially swap backwards and forwards between source takes. But in the end you should have something that represents an entire piece or movement. Put the mouse pointer over the beginning of this new edit and press A to hear it. It should be complete, but the transitions from take to take are likely to be clunky, despite being equipped by default with short crossfades. Which is why ReaClassical has its own dedicated Crossfade Editor...

ReaClassical’s fade editor works differently, with vastly better clarity and flexibility, courtesy of a dedicated two‑lane fade editor.

Fading Up

Any good DAW, including Reaper in its standard form, can make crossfades between abutting or overlapping sections of audio. But a problem is that you’re forced to work in a single track lane, with the waveforms of the audio involved overlapping and thus potentially being obscured. While that’s fine for a single fade on one track, it’s not very useful for multitrack work that positively relies on crossfading, and might include hundreds them, all of which need to be perfect to the point of complete inaudibility! ReaClassical’s fade editor works differently, with vastly better clarity and flexibility, courtesy of a dedicated two‑lane fade editor. It’ll show the end of one audio region and the beginning of the next separately (ie. either side of the potential crossfade). Next up, then, I’ll take you through the basics of this, which may seem unfamiliar to begin with but will, I promise, soon become second nature.

ReaClassical’s Crossfade Editor literally opens up the business of crossfading, showing either side of an edit in separate lanes. It effortlessly takes care of multitrack groups, and ripples subsequent material to maintain timing. Here a crossfade point has been marked just before a transient, with item waveforms extended to help reveal it.

In your clunky assembly edit, scroll back to the start and select its first item. Press F to open the Crossfade Editor. The normal track group display is now replaced with two lanes: the red item is the one you’re going to fade from; and the green item is the one you’ll fade to. What’s needed now is information: you need to hear the edit as it stands, to gauge how near or far it is from being correct. It might be close or, very likely, there may be a beat or two missing or duplicated.

The best way to check this is, once again, to use the A (audition) keystroke. Put the mouse pointer over empty space in the lane above or below the red item (I say that because the item could itself appear in either lane), and press A ReaClassical plays across the edit to a mirror point on the other side. If you’d moused over the red item directly you’d get playback from your pointer up to the edit, and if over the green item, from the edit to your pointer.

Assuming it’s not already perfect (possible, but unlikely!), point again into an empty lane area and press Z. This extends the waveforms of both items so that they overlap, the idea being that this’ll help you spot the matching shapes of matching musical material. Transient peaks and spikes are particularly useful for this. Assuming you can see some correlation, as in the screenshot, then the next steps are easy.

Click in the red item where you want the crossfade to occur; just before a transient is always a good candidate. A cursor is placed as a clear visual guide. Click and drag the green item left or right to line up its matching transient vertically and, finally, press X to re‑trim the items and write the new crossfade — which you’ll immediately need to audition again to see how successful it was.

No good? Listen more, press Z again, try a different crossfade point or timing, and then X to make another new version. Like it? Good. In this case, we want to move along to the next edit whose crossfade needs polishing. Having to locate that manually would be a drag but, without leaving the Crossfade Editor, pressing W takes you straight to the next edit — then you can work on that one just as you did the last. In fact, W is actually part of a pair of shortcuts, together with Q, that go left and right between edits (and items generally), so you can fix all fades in an assembly edit in no time. And when that’s done, pressing F once again leaves the Crossfade Editor.

Second Sight

In an ideal world, our assembly edit and fade work (what might be termed a ‘first edit’) would result in a perfect musical product. In reality, it’ll probably need more polish: anything from repairs of individual notes to replacing longer sections. This is the moment we utilise true ‘four‑point’ S‑D editing. Compared with our assembly edit (which was technically a ‘three‑point’ edit), there’s one difference: we mark both IN and OUT points for the source material and the destination within the existing edit.

A four‑point edit is where you specify in and out locations in both the Source material and the Destination ‘best bits’ composite — it lets you carve into an existing edit to make later improvements, maintaining all other edit points and crossfades around it. Here a four‑point edit is about to replace an existing edited section that includes a crossfade.

Imagine an edit you’ve made that needs just one tweak: a new, alternative section to be dropped in, in one place. Use the audition action (A) over your edit to find out where the section in question starts and finishes. Mark it with Dest In and Out markers (keystrokes 1 and 2) and then go back to your source material and audition that to find a better alternative. Mark that with Source In and Out (3 and 4). Then, pressing 5 executes a ‘make S‑D edit’: it lifts the source material, drops it to the destination, and ripples everything that follows along the timeline, including any fades you’ve previously worked on. ReaClassical also helpfully scrolls to the location and places the play cursor at the end. Remember, though, that this new region will likely need fade work to transition in and out of it, so select the item before it, enter the Fade Editor, fix the ‘in’ crossfade, and press W to move to the ‘out’. Fix that, and you’re free to leave the editor.

Next Steps?

As this is an introduction to ReaClassical, I’ve kept things fairly high level, and only run through some of its most potent core editing functionality. But while there should already be plenty here to get your teeth into, its abilities extend further — much further, in fact. You can perform S‑D editing with time‑stretching, for example, and there’s flexible signal and effects routing in the mixer, support for reference tracks and ‘room tone’ (recorded silence, used to pad transitions between tracks), snapshot‑style automation, some great mastering‑style plug‑ins, and even CD authoring and DDP file creation. The developer (chmaha) also tells me that there’s much more on the horizon. So there’s lots more to explore here if I’ve piqued your interest!