I bought these for solving a specific problem in my vocal booth. This space was already quite well treated with heavier traps, but on louder singers my more sensitive condenser mics picked up some slight mid/hi reflections that, although mixable, started getting under my skin and also ended up posing a real problem for a specific vocal session where a shouty vocalist was very prominently featured against a sparse, delicately instrumented track. It turned out good in the end, but required far more "fixing it in the mix" than I prefer.
After this session, I ordered both these wedge styled ones as well a couple of pyramid panels, and they did indeed quickly solve my problem. A bunch of panels, a couple of bags of industrial velcro, some super glue, and the next vocal session got me the results I was hoping for.
As a side note, they also work as an excellent companion to a more seriously bass-trapped control room, giving the engineer more control of the mids and above if needed. I recently helped a friend and colleague set up his professional post-production room (5.1 monitoring, sub reaching down to 19 Hz) and when the major bass control work was done, along with some strategically placed diffusor panels, we added a whole bunch of these wedge and pyramid foam panels to "seal the deal" at certain areas where there was still too much flutter and reflections going on. This room now sounds amazing, and it's a pleasure to work from there. I will definitely be adding some of these to my own smaller control room in the future, which already features plenty of heavy bass traps.
In conclusion, these wedge styled panels do exactly what these kind of panels are supposed to do; controlling bass waves they will most certainly not, but for early upper frequency reflections they are pretty much perfect.
