To kick off this column, I want to talk about one of the most fundamental concepts to remixing: time-stretching. It''s a critical technical process to understand when doing a remix, and changing the tempo is one of the quickest ways to get your version to sound different from the original. It''s usually necessary to time-stretch to get the vocals into the right tempo range for the genre your mix is targeting. I mainly produce club/dance remixes, which have typical BPM ranges in the upper 120s.
ALL ROADS LEAD HOME
Time-stretching capabilities are not new to DAWs, and today most of the major programs let you go beyond the basics, allowing you to warp, bend, flex, and follow any tempo change. No matter what software you choose, it is always best to take a bit of time at the beginning to find the original mix''s tempo and line up all of the original tracks or stems that you have for the project.
If you have a choice, request the vocal tracks in as separated a format as possible, with the lead, harmony, and any ad-lib tracks as individual stems. This will make time-stretching easier and usually give you better results. When there are FX tails on a track or multiple voices mixed together, the stretching algorithms can sometimes get confused and the result can be digital artifacts in the stretched file. When everything is separated, you will get cleaner results and have more creative control to rearrange sections and come up with some completely new vocal parts.
FIG. 1: This shows the original mix with the a cappella vocal track lined up underneath.
It''s also useful to have the full stereo mix of the original song lined up in your session for reference (see Fig. 1). It will make it easier to find the tempo and key if necessary, and you can line up the a cappella vocal files in time against it. This makes it a lot easier to identify a downbeat, which is critical for lining it up at the new tempo. If you have access to the original project''s DAW file, then everything is already lined up and the tempo is right in front of you. If I am not planning to change the tempo that much, then I will also time-stretch the original mix, which can sometimes lead to interesting new parts and loops that you can process and further edit to sound different.
Once you have the original tempo figured out and everything is lined up, you can then start to think about how far you need to stretch things to get them in the desired tempo range. For example, let''s say you are doing a dance/club mix and you want the tempo to be around 128bpm. If the original song is 115bpm or above, then you can be pretty sure you will have no problems. If the tempo is a ballad, let''s say 70bpm, the chances of stretching the files up to 128bpm and having it sound decent are slim.
However, you can slow the tempo of the vocal files down to, say, 64bpm and have them play at half-time against your 128bpm musical bed. However, songs whose original BPM is in the mid 90s end up in what I call no-man''s land for dance remixes. It is usually too much of a stretch to go up to the 120s or down to the 60s for half-time. This is especially true if it''s a spoken word or a rap vocal. In these cases, I will take it as high as I can—either I''ll get it to sound good in the lower 120s or have to switch gears a bit, creatively.
TRUST YOUR EARS
By taking some time at the start of a remix to organize the files, find the tempo, and line up and stretch the vocals, you will set yourself up to stay in the creative flow. And the most important thing to remember is to trust your ears—not only when it comes to time-stretching, but with all aspects of your musical creation process. Θ
Vincent di Pasquale is a producer/remixer who works out of his project studio (vcdstudios.com). He has remixed songs for One Republic, Madonna, Nelly Furtado, and many others; and is the author of The Art of the Remix, a comprehensive interactive remixing course available now at faderpro.com.