Not sure what you mean, but, you can load them into a Reaper file, starting, not at 1.1, but moved over, then export a new .mid file.

Hi Marat ” src=”/wp-content/uploads/invision_emoticons/default_SA_smile.gif” /> Saw your email but I might as well reply here in case others are curious, since it’s a tricky process. Here’s how you can do it in Reaper.

Screenshots for each step and a different version of this explanation (I’m on Mac and a newer Reaper version but everything should be similar): http://imgur.com/a/PTEOk

First take the number of seconds you want to add and figure out a number of beats and a tempo that works to make up that number of seconds. This is a bit of guesswork but here’s an example of the steps:

1. Take your number of seconds, let’s say 2.5.

2. Divide this by some whole number of beats to try and fill it up. We’ll try 5 beats. So 2.5 / 5 is 0.5.

3. Take that number and divide 60 by it. So 60 / 0.5 is 120, which is the tempo in beats per minute.

4. So, you can make 2.5 seconds of space by having 5 beats at 120 beats per minute. If this tempo you ended up with is not in the range of 40 bpm to 300 bpm, you’ll need to try again from step 2 with a different number of beats. (That’s the range that Magma/RB allows.)

Got a tempo and beat count? Open a new REAPER project. Make sure the cursor is at 1.1.00, right at the start. Go to “Insert > Time signature/tempo change marker”. Set the tempo to the value you found, check “Start new measure”, and put in N / 4 for the time signature where N is the number of beats you found. After you do this, the point 2.1.00 (after one measure) should be, in seconds, the amount of time you wanted to add to the MIDI.

Then, drag in your original MIDI to the point 2.1.00. Make sure the two checkboxes “expand tracks” and “import MIDI tempo map to 2.1.00” are checked. It should make several new tracks.

Drag the left edge of those tracks to extend them back up to 1.1.00, so they start right at the start of the project. Then you’ll need to open each track and move the Track Name event to 1.1.00. Double click each track, find the Track Name event which should be at 2.1.00, and move it back to 1.1.00. Also: I believe there is a bug in Reaper’s MIDI import function where it puts an extra track name event (the one from a MIDI’s tempo track) into the first imported MIDI track. Make sure you delete this extra one, if you see 2 track name events in the top track.

Finally export the new MIDI file with “File > Export project MIDI…”. Make sure “Multitrack MIDI file” and “Embed tempo map” are selected.