All:
I have been trying out the Eighth Nerve Response Controllers for corners, and have finally listened enough to give a decent review.
I got 4 of the corner controllers. I really wanted to compare them to the Michael Green Pressure Zone Controllers that I was using. I had been concerned with the Michael Green controllers because they don't seem to eliminate that horn loading effect in the corners. They are much better than nothing, and actually work pretty well, but they way they are designed, they don't fit all the way into the corner, so there is still some space where sound pressure can build.
Anyway, tonight I actually did some listening. First I did it with no treatment. I listened to Bill Frisell's Blues Dream, which is a fantastic album with lots of etheral guitar, and horns. This disc sounds really good, and it was hard to tell that there were really faults with no room treatments. Things seemed to ring longer than with treatments, and the sound took on a bit of a harsh characteristic. That's strange b/c I have an all tube system with a tube DAC.
I installed the Pressure Zone Controllers next. Everything got smooth again, and things stopped echoing as much. This introduced just the right amount of room ambience, and nothing more. These devices are successful at absorbing the frequencies that make the sound harsh, and it also minimizes the impact of that pressure area in the corners.
The sound was much more natural, and smooth with PZC's. I noticed that things were clearer, and crisper. You could hear more of the natural decay of the instruments, which was smeared before.
Overall I was pleased with the PZC. They have been a mainstay in my system for a long time.
I was anxious to try the Eighth Nerve controllers just because I no longer needed a ton of treatment to correct my room anomalies. I took out the vast majority of the PZC's I did have, and sold them. I noticed that they were extremely effective in my old raggedy room, but in the new room, they absorbed a huge amount of sound! They took more than they brought to the table.
So I wanted to try these b/c they do cover the entire corner, and don't let any sound get back there like the PZC.
Anyhow, I took down the PZC's, and I put up the Response Controllers in the corners. They are ivory in color. Immediately upon starting the Frisell disc, I noticed that there was more music present. But it didn't go back to the strangeness of NOT having treatments. Things really cleaned up quite a bit, and I noticed an immediacy to the music that was not there before. There was a nice increase in attack on the double bass, and also there was more decay.
I noticed a more 3-D soundstage than I had before. I suspect this is due to the horn loading of the corner being virtually eliminated. These don't seem to absorb as much of the music as the PZC's. I felt a more complete sonic picture had been presented to me.
I will say that I am anxious to get a few more of these for other parts of my room. I think that with PZC's, 4 was enough, and 5 was overkill. These seem to be less harmful, and maybe a few more would be just right.
Nevertheless, if you have not treated your room in any way, I would encourage you to do so. These seem to be the most reasonably priced treatments that do the least harm to the music. When you start talking about foam, and all that, I get scared b/c I know the absorption of those materials is incredible, and that is just no good for music.
If you want to listen in an anechoic chamber, I can see placing foam all over your walls, but treating a reproduction room is a delicate balance between chaos, and sonic murder. You don't want the sound waves to have free reign, but you don't want to kill them either.
In summary, these are the best products I have tried for treating the corners in a listening room. They will add many things to your sound by taking away the smearing, and collision of sound waves in the corners.
Highly recommended.
B