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View Full Version : speaker problem, processing problem....?


KU40
07-23-2007, 08:55 AM
I built 3-ways for the center, left, and right channels that consist of 8" Dayton Reference, 6" Dayton Reference, and 1" Dayton classic tweeter. The crossover points are 80-300 for the 8", 300-3000 for the 6", and 3000+ for the tweet. I built the 8's into 1 cube tuned to 60 hz I think and have the 6's in sealed enclosures within the whole enclosure, I forget the size though, maybe .3 cubes. I'd show pictures but my internet at home isn't working right now.

Anyways, my problem is mostly with hearing talking in movies. I use the Dolby Digital processing on my receiver (It's a pioneer something or other, like two years old) for movies, and sometimes it's just hard to hear the voices, but every other sound is fine/great. Everything else comes in great, music sounds terrific on them (though usually I use other processing for that, like Advanced Music). Some TV stations will sound ok, some have the same voice problem. Is this normal for dolby processing, or should I change up my center channel to something that has better midrange (like MTM with 5's and a tweet, for example)?

One thing that may be a problem now is that the center channel is a tad below eye level when sitting due to it's box being so heavy that I can't sit it on the TV and haven't gotten a wall-mount TV stand for it yet. It's below the TV. Could raising it up above the TV help with this? One of my roommates is moving out and I'm hoping to move this all up into his bedroom for a home theater room. The room it's in now is a rectangular living room that's got quite a few odd places (kitchen, hallway, low ceiling in half, raised ceiling in half) that aren't great for acoustics, and it's facing sideways in the raised ceiling portion.

BTW, the rest of my system consists of MTM's for the surrounds (used to be my mains, that's why they're MTMs instead of just MTs) with 7" Vifa MG's in 1 cube for both tuned to 50 hz or so and 1" Peerless soft domes. For the sub stage I have two 12" Crossfire BMF's left over from an old car install in 5 cubes tuned to 24 hz and a 500 watt plate amp from PE. the subs definitely suffer from the acoustics because if you sit in line with them you can barely hear them, just feel it, but go off-axis or down the hallway and it's insane.

doc
07-23-2007, 09:27 AM
Er, it sounds like your center channel isn't getting the proper signal... Does it make any noise running one of those 'setup' pink noise tests? If not, it either isn't plugged in (heh!) or a setting somewhere in the receiver is not correct.

If it DOES make noise, then perhaps you can increase the center channel's level on the receiver to compensate?

I only say this because what you are describing, some tv shows sounding correct and others not, would be a symptom of your receiver switching to 2-channel stereo on a non-5.1 broadcast thus using your left and right mains for all audio. A 5.1 encoded signal would attempt to use the center channel for dialouge in the same way films do, so if there is a problem with dialouge, there is a problem with the center channel. If the dialouge sounds normal when using the L and R mains (which are the same design as the center, correct?) then there is no reason speaker or driver wise it should sound any different through the center channel.

KU40
07-23-2007, 10:29 AM
ha, yeah it's plugged in. I've put my ear up to each component of the center channel to make sure, and to see if one of the speakers over another was the culprit, but couldn't distinguish a problem. and yes the front three TMW sets are all designed identically, except the L + R are in a tower setup, whereas the center channel has the woofer on the right and the tweet above the mid on the left side of the front baffle.

The center channel is in front of the mains, though. The mains are all the way against the wall but the center channel is about 1' in front of them because I had to sit it on top of the sub enclosure, which serves as a base for the TV as well, which is all the way against the wall (behind the center channel). I do have this compensated for in the receiver, however, as the mains are set to like 8' away but the center channel to only 7'.

i may need to play with it some more, maybe switch wires between the center channel and one of the mains to see if it does it there as well, which would indicate a processing problem instead of an equipment/placement/front baffle speaker arrangement problem.

95Honda
07-24-2007, 06:07 AM
I would shy away from an MTM for the center unless you can orient it vertically. The horizontal arrays are a horrible idea because of the narrow beamwidth they will throw out and were purely used for home theater for looks...

I would listen to your mains in regular 2-channel stereo. Listen to some of the same movies you were having problems with, again in 2-channel stereo, 100% of the sound from the 2 mains. If you have a drop in dialog still, I would look at possibly changing something in the loudspeakers, if not your all good.


I have had many problems in the past with dropping dialog even with well designed systems. The large theater I built in the Middle East was plauged with the same problems until massive amounts of tweaking was done. Also, the different formats that are used in different movies throw everything off, it pisses me off when you have to switch processing modes with different movies.... I hope this helps in some way...

KU40
07-24-2007, 09:12 AM
yeah it does, thanks a lot