I have had to replace four amplifiers in my subwoofer because of audible distortion at the area around speech. Changing the crossover would make the distortion from the subwoofers change slightly but I never measured or got an idea what that did. Since changing out the amps the audible distortion did not sound like a digital mess any longer, and I have been able to enjoy movies most of the time. The problem I seem to be having comes and goes, and I am having a difficult time finding if it is related to my room, maybe a subwoofer box that needs damping, distortion, setup, or even the movie I'm watching. It is a very directional sound from the left side of my room. In my waterfall plots, the decay in the left seat does not show any ringing that would lead me to think it is related to the subwoofer being near the corner. When I stand over the subwoofer in my left corner however I can hear that the subwoofer is making noise that is sounding similar to the problem I hear, and I am unable to hear it standing over the other three subwoofers that are near my front wall. One of my subwoofers has carpet in it in place of the damping material because I used this to cover other to cover areas in subwoofer boxes that had slight gaps. If this is the subwoofer that has some carpet in it I am unsure, but the sound problem seems around the area of the ports. To make things more confussing, this is also an area in my room with bass build up, but I was not aware this might cause sound directly next to a subwoofer to sound boomy. Would that be a possibilty? Then there is the only other thing that I could think that might cause it which is distortion. There seems to be some higher levels of distortion around my crossover area when I measure sine waves on a CD I made. Do these graphs bellow look like it might be something loud enough that is audible? When I measured them my meter began to clip at 80Hz until around 84Hz, and measured as high as 89dB in REW, but I did not have the meter calibrated. I had taken sweeps that were at -1dB FS and reduced the level by around -20 or -33 in Audacity. Sorry that I forget which one but I think it was -33. I measured with my subwoofers and the right speaker.
The problem I hear while watching movies is really strange. For example in the begining of Saving Private Ryan it sounds fine for the first few moments, then when they get closer to explosions, the sounds of them sound very localizable on the left side of the room when they are very long sounding. Then the problem seemingly is gone when they are off the beach throwing granades etc. After the get orders and are off on the mission there is then some more localizable bass there in the scene that is also like the menu of the DVD where they walk against the background of explosions. After that it seems like there are not much more problems there. I was watching a different movie last night and something similar happened. There was a moment when there was very strong localized bass from the left corner that was a very long amount of time. It almost seemed to come from the front wall also. Then later there was the same sounding frequency that was much louder and it was not localizable at all and sounded very undistorted. That sound seemed to be almost as long sounding so I can't tell if it's bass build up. :gah: Could it be that very subtile difference that I hear when I improve the sound of the subwoofers by adding more power? If that were true than why would I hear it only in the corner? I'm not sure how else to address the issue and it does not seem related to other side of the wall. The problem corner is at the left front corner next to my partition wall, and the other walls (including ceiling which also has steel) all have the concrete foundation. There is a good amount of room treatments in the room. If you have questions about the treatments or equipment let me know. I will try experementing with the room treatments around this area and see what difference I can make, but I would like to know if this might be something to do with the crossover again. I do not hear this problem with music. If this is a crossover issue I'm not sure how to deal with it. Sorry for the long post. :sad2::unbelievable::bigsmile::scratch::help:
The problem I hear while watching movies is really strange. For example in the begining of Saving Private Ryan it sounds fine for the first few moments, then when they get closer to explosions, the sounds of them sound very localizable on the left side of the room when they are very long sounding. Then the problem seemingly is gone when they are off the beach throwing granades etc. After the get orders and are off on the mission there is then some more localizable bass there in the scene that is also like the menu of the DVD where they walk against the background of explosions. After that it seems like there are not much more problems there. I was watching a different movie last night and something similar happened. There was a moment when there was very strong localized bass from the left corner that was a very long amount of time. It almost seemed to come from the front wall also. Then later there was the same sounding frequency that was much louder and it was not localizable at all and sounded very undistorted. That sound seemed to be almost as long sounding so I can't tell if it's bass build up. :gah: Could it be that very subtile difference that I hear when I improve the sound of the subwoofers by adding more power? If that were true than why would I hear it only in the corner? I'm not sure how else to address the issue and it does not seem related to other side of the wall. The problem corner is at the left front corner next to my partition wall, and the other walls (including ceiling which also has steel) all have the concrete foundation. There is a good amount of room treatments in the room. If you have questions about the treatments or equipment let me know. I will try experementing with the room treatments around this area and see what difference I can make, but I would like to know if this might be something to do with the crossover again. I do not hear this problem with music. If this is a crossover issue I'm not sure how to deal with it. Sorry for the long post. :sad2::unbelievable::bigsmile::scratch::help:


