Noob Tempo question - changing tempo without affecting recorded tracks

Tobe

Simon
New to reaper and loving it, and beginning to play with tempo.

What I want to do is record a simple guide track of vocal or whatever and use that to determine the tempo of a song. Usually I just want to get a general guide for the tempo of the whole song (and discard the guide), but it would also be nice to tap in a map for songs that may want tempo variations... but I don't want to change the rate of the recorded tracks/items or their positions in time. I want them to remain at the rates and positions (in time) they were recorded at.

However, on the default settings, if I start tapping the tempo, then everything moves about and the rates or recorded tracks/items all change to fit the new tempo generated from my "tapping". The default seems to be for people wanting to use loops etc... but I use mainly naturally recorded material and just want to set the tempo for MIDI components, not recorded components.

I hope that makes sense.
 
It's built into many sequencers = logic and cubase, for starters. Tempo maps are what they are called in cubase. It can generate them automatically if the song has strong beats it can detect, but I tend to do it be ear and eye - matching the waveform in the display to the bar grid, tweaking tempo up and down until it matches - works fine for me, although a bit labour intensive. I'm not sure if Reaper and the others have the same facility, but if you can see the waveform and the bar markers, then adding tempo changes manually as midi events was how I did it years ago, and I'm sure that's possible.

There's a good article on reaper tempo mapping on the SoS site.
 
Last edited:
Thanks Rob,

Cubase 6 (I used the "artist" cut down version) has a beat count thing that you can use on recorded material to get a guide for the tempo without affecting the recording, and you could then use that for the overall tempo and then go and adjust things. What I like about Reaper is I find it usually has more powerful tools once I figure them out.

I "feel" on using Reaper that there is probably a way to tap a map off recorded material, but I would be happy for a start just to get a ballpark tempo off the recorded material without affecting it.
 
Here's what I do - record a guitar scratch track at a set tempo (I use EZ Drummer, and just pick a simple repeating beat pattern that works for the song, but you can do it with the metronome, too) - the main verse tempo, typically. I then map out the song (verse 1, chorus1 , bridge, etc) with markers. If I want to speed up or slow down the tempo at any sections, I do so, then re-record the scratch track, make sure it works, adjust if it doesn't.
 
Thanks mjbphotos,

This is the bit I needed from the SOS article... haven't tried it yet, but it seems to be talking about what was giving me grief. My scratch takes were getting stuffed around when I played with the tempo...

The first thing you need to do is select all the Items in your project (Ctrl‑A), open the Item Properties dialogue window (press F2 and click the subsequent ‘All At Once’ button), and select ‘Time’ from the Item Timebase pull‑down menu. This prevents any Items from time stretching during the tempo‑mapping process.

Right‑click the Locking button in the main toolbar and set it up so that there are ticks in both the Enable Locking and Items (Prevent Left/Right Movement) boxes. This stops any audio shifting around while you’re extracting the tempo information. If your initial recording is in multitrack format, it also makes sense to Group all those Items together for the time being (select them all and type ‘G’). However, for the sake of simplicity I’ll assume that we’re working with a single mono/stereo audio Item.
 
alt + enter to bring up project settings
"Project Settings" tab
Set "Timebase for Items/envelopes/markers" to "time".

This will prevent changes to the tempo of the project (either master tempo or via markers) from moving or editing existing media.
 
Back
Top