Are You Leading or Following?

How to make useful tempo maps for recording sessions, Part 2

Click tracks are often used in music recording, keeping ensembles playing tightly together and helping ensure that specific musical events happen exactly when they need to, as when scoring to picture. As discussed in part 1, a good tempo map will generate an audio click track that leads musicians easily and musically through performing a piece of music.

Your DAW session midi might STILL not be good enough

Recently, I was recording and mixing a project that was scored to picture. The composer did a wonderful mock-up in Logic, but as it was a tango we decided to replace all the programmed instruments with live players.

The composer (who really did a killer job on the piece) made some quick adjustments to the tempo map in Logic to create printed parts for guitar, violin and cello, saving him the time of transcribing what he had played. Unfortunately, this resulted in a click track that reacted to, rather than predicted, all the tempo changes and a printed score with phrases broken up unmusically across measures of frequent meter change. This rendered the click and the printed score unusable as it put the player’s focus on counting through tricky measures rather than playing the written lines as musically as possible.

You can imagine how hard it would be to come up with a guitar performance like the mock-up if all you had was this click track.

Better, Stronger, Faster (and sometimes Slower)
To solve this problem I loaded the composer’s audio files and tempo map into a new Protools session and had a listen to it. I made a sketch of the piece (starting with the main instrument, guitar) in what I felt was the most constant meter, 4/4. Once I had a road map it was then easy to create a new tempo map in Protools [note that the new tempo map still hit all visual cues identically to the original map] that the guitar player could listen to and re-create the midi part.

Lock and re-load

The mechanics of creating and adjusting tempo maps are specific to each DAW system, but there are important things to know before you begin on any platform.

When you make changes to your tempo map or conductor track, it will make changes to any tempo or tick based (unlocked) midi tracks in that session. So always make safety copies of your session before making any tempo edits (of course, you do that already.)

The simplest way to remap a piece without worry is to work from audio rather than midi files. Again, be sure to set all audio tracks to timecode base and disable any elastic audio or flex-time. This way your composition is locked in and changes to the tempo map will have no effect on what you are mapping to, keeping you from chasing your tail! If you need to maintain your current tempo map (as you might if you are still choosing sounds or still editing your composition), you can always make rough audio files of your composition in it’s current state and open them in a new DAW session that you can then use for re-mapping and recording your live instruments in. Later you can move your newly recorded audio back into the original session if need be.

Of course, these methods do not help if you are planning to generate a printed score part from the DAW. To do this you’ll be re-mapping a session with midi information in it, so you’ll need to freeze or lock all midi tracks before you re-map. If you don’t, any changes to the tempo map will effect the timing of your midi, changing playback.

Check the user manual for your DAW for the specifics on locking or freezing midi (freezing midi as midi information is different than freezing it as audio, be sure to do the former.) In Protools this can be done by changing each midi track to sample based rather than tick based timing. If you want midi events in Logic to keep their positions regardless of tempo, you can lock them to SMPTE time.

Now you can manipulate the tempo map manually or using tap tempo (tapping along with your piece is often a quick way to get a smooth, musical map). When mapping manually, going measure by measure can result in an unsteady, jumpy click so try to go the longest amounts of time you can before making subtle adjustments to tempo, and then use significant beats to adjust to. Be sure to have a click to listen to while making all tempo map adjustments. If the click sounds annoying or hard to follow you’ll want to change it. NOTE: for the purpose of this article, I am ignoring beat detection, auto beat mapping, etc, but most of these tools do work with a bit of tweaking.

Make your print music match your map

Though vastly improved these days, printing a playable score from a DAW is still tricky and does depend greatly on a carefully crafted tempo and meter map. Often it is simpler to export your midi to a notation program (like Finale or Sibelius) or even to write parts out by hand (many times, hiring a skilled copyist can be the most effective solution). Regardless of how you create your playable score, you’ll need to be sure that it matches your click track in meter, number of measures and tempo events.

If your music is one solid tempo, simply note the tempo, click subdivision and meter at the top of your chart and off you go. If, however, you have varying tempi and meter you’ll need to go through and mark all accels, rits, ralls, etc.

Tempo changes should be marked over the staff and specifically over the section of the measure where the change begins. If a rit. begins on beat 3 of a measure, try to place the marking over the middle of the bar if possible.

Subdividing the click further during big tempo changes can be helpful, but be sure to mark any changes to click subdivision where they occur.

Coda

The more useful information you include in your printed music, the better your chances of running a pleasant, professional and cost effective recording session.