In this installment of Obscure Audio Software, we’ll be taking a look at a freeware program called SPEAR, an acronym for “Sinusoidal Partial Editing Analysis and Resynthesis”. In a nutshell, it allows you to view and edit a sound as a visual representation of its individual frequencies (partials), and then resynthesize the sound. The resynthesis isn’t exactly identical to the original sound if you just load something and press play (and the website mentions this up front), but is very close. I don’t really consider that an issue though, since I’m usually using this to mess with a sound anyway. It apparently hasn’t been updated since 2009 (ed. note: the program has received an update as of Sept. 22, 2018), and the website says it is unfinished feature-wise, but I’ve never had any stability issues or bugs that I’ve noticed. There is, however, at least one menu item (“Select by rule”) that pops up a message about that feature not being implemented yet. The program is very usable in its current state though, so don’t let that stop you from checking it out.
SPEAR can do relatively obvious things for a program like this, such as pitch shifting and timestretching, but takes these things further by allowing you to do them to individual partials, or multiple selected partials (or sections thereof). There are tools to select regions by time or frequency region, as well as rectangle and lasso selct tools that work like their counterparts in image editing software. You can also select all partials below a specified amplitude or duration. The familiar editing actions like cut, copy, and paste are present, as well as some other fun stuff like frequency flipping.
SPEAR has a few other tricks up its sleeve as well, like the ability to subtract two sound files from each other, and a scrub mode for playback that can be fun to play with.
Grab your SPEAR
Overall, though SPEAR is based on a fairly technical concept, I think it does a good job of making that concept easy and fun to work with. For most people, it probably isn’t going to see daily use, but I think it would make a great addition to anyone’s arsenal of audio tricks.