Out of Phase Speakers and AVIA question... [Archive] - Audio & Video Forums

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MCF
04-04-2005, 06:05 AM
I ran my AVIA DVD yesterday and was doing all the tests...when I ran the test for FL and FR to determine if they are in phase, according to the AVIA DVD, the speakers are not in phase (at least as far as I could tell by listening to the test). I double checked all the +/- connections and the speakers and receiver and they are connected correctly. Should I ignore the test or actually reverse the connections on one of the speakers as recommended by the AVIA DVD...sounds odd....

kexodusc
04-04-2005, 06:41 AM
Whoah, MCF....I have a real problem with the audio tests on AVIA and DVE and most other test programs...I think they assume too much for someone to just jump right in there, it's not as simple as just listening to any setup and saying "yup, their out of phase". If your system isn't well setup from the beginning, you might be expecting the system to pass the test with flying colors when it's just not possible.
First, are your delays and levels matched properly, is toe-in the same for FR and FL, and are the speakers placed reasonably away from walls and corners?
If not, any of these variables can contribute could cause you to believe the speakers are out of phase going by those test DVD's...
What receiver do you have? Does it have an auto-setup feature that checks for phase?
How do your speakers sound? weak in the bass, no center image, and very delocalized or are they fine for music?
Since you've checked the connections thoroughly, I'm tempted to think that there's something else going on here.
It is possible that a wire got reversed inside the speaker, but this would be an exceptional circumstance.

MCF
04-04-2005, 06:56 AM
Whoah, MCF....I have a real problem with the audio tests on AVIA and DVE and most other test programs...I think they assume too much for someone to just jump right in there, it's not as simple as just listening to any setup and saying "yup, their out of phase". If your system isn't well setup from the beginning, you might be expecting the system to pass the test with flying colors when it's just not possible.
First, are your delays and levels matched properly, is toe-in the same for FR and FL, and are the speakers placed reasonably away from walls and corners?
If not, any of these variables can contribute could cause you to believe the speakers are out of phase going by those test DVD's...
What receiver do you have? Does it have an auto-setup feature that checks for phase?
How do your speakers sound? weak in the bass, no center image, and very delocalized or are they fine for music?
Since you've checked the connections thoroughly, I'm tempted to think that there's something else going on here.
It is possible that a wire got reversed inside the speaker, but this would be an exceptional circumstance.

The system sounds fine...the FR and FL and toed in about the same and are at the same elevation. They are Klipsch RB-25's. The FR is closer to a wall because of installation limitations. I have an HK AVR-635. No check for phase.

kexodusc
04-04-2005, 07:23 AM
I've always noticed a large bass suckout when speakers are wired out of phase...I'm guessing that the AVIA test (if it's anything like others I've seen), doesn't do the greatest job here...Typically these test discs do a sharp focused left, center, and right image, and then do a delocalized sound up front for you to compare to...you should hear the sharp image when the disc says so, and vice-versa...The problem is every room, system, etc, is different so it's not that easy...
If you have an SPL meter, I suggest you double check the levels so that they are matched...this can affect the sound quite a bit, even if only 1 or 2 dB off. Also double check the levels.

I haven't seen the AVIA sound tests yet, so if they are considerably different than others I've seen, then I apologize, but I find it hard to believe you have a phase problem.

MCF
04-04-2005, 08:27 AM
What you describe is how it is tested....I am going to leave everything the way it is since I am happy with the way it sounds...except the little cheap 8" JBL sub....waiting for my PB Plus/2 sub...that should complete my setup...

Quagmire
04-04-2005, 09:20 AM
I ran my AVIA DVD yesterday and was doing all the tests...when I ran the test for FL and FR to determine if they are in phase, according to the AVIA DVD, the speakers are not in phase (at least as far as I could tell by listening to the test). I double checked all the +/- connections and the speakers and receiver and they are connected correctly. Should I ignore the test or actually reverse the connections on one of the speakers as recommended by the AVIA DVD...sounds odd....
MCF,
I replied to your earlier thread regarding the problems with your center channel speaker and as I recall, an out-of-phase condition is one of the things I listed as being a possible culprit for causing the problem. I also suggested that your out of balance arrangement of the front three speakers could be problematic. Has any of this changed? You state that you are now "happy" with the sound although the test disc indicates you could have a phase problem. If the front speakers are arranged in a non-typical or non-symetrical way it will be very difficult to test for propper phase. This may cause them to sound out-of-phase even though they are wired correctly. As I mentioned in my reply to your earlier post, you may try moving the speakers around (only temporarily) just to test the setup, then you can place the speakers back to meet the limitations of your installation. It's too bad you're stuck with this placement arrangment because even if everything is setup correctly the placement issues are undoubtibly causing poor system performance. Just curious as to what has actually changed since your thread about the center channel speaker?

Q

MCF
04-05-2005, 07:44 AM
I ran better speaker wire to the center and front right...they were using cheap pre-run wires. I also lowered the front left and front right speakers down a bookshelf level (about a foot) and also moved the front left in about a foot to reduce the difference between the front left and center and center and front right (still about a 5 ft larger space between center and FL and center and FR). I confirmed that EVERYTHING is connected appropriately to the reciever and double checked all speaker leads making sure there was good contact. I also used an SPL meter to set all speakers to 85dbA using AVIA; however, nothing dramatic came out of this...all speakers are set to within +/-2db on the setup menu of the reciever to get them all to 85dBa with master volume at 0. I also increased the treble to +8 to increase audible level of dialogue. I am still not 100% happy, but much happier now. I am planning on getting a large rug for the hardwoods and hanging a tapesty on the back wall to 'soften' up the room some. I think this will make the biggest difference overall.

Quagmire
04-05-2005, 10:25 PM
I ran better speaker wire to the center and front right...they were using cheap pre-run wires. I also lowered the front left and front right speakers down a bookshelf level (about a foot) and also moved the front left in about a foot to reduce the difference between the front left and center and center and front right (still about a 5 ft larger space between center and FL and center and FR). I confirmed that EVERYTHING is connected appropriately to the reciever and double checked all speaker leads making sure there was good contact. I also used an SPL meter to set all speakers to 85dbA using AVIA; however, nothing dramatic came out of this...all speakers are set to within +/-2db on the setup menu of the reciever to get them all to 85dBa with master volume at 0. I also increased the treble to +8 to increase audible level of dialogue. I am still not 100% happy, but much happier now. I am planning on getting a large rug for the hardwoods and hanging a tapesty on the back wall to 'soften' up the room some. I think this will make the biggest difference overall.
Wow! Really sounds like you're on the right track. I'm glad you're much happier with the system. Your placement options leave you with less than an ideal setup, but you are certainly making the best of it. Kudos.

Q

kexodusc
04-07-2005, 09:37 AM
MCF: If your left speaker is 5 feet further away from the center, try shifting yourself 2-1/2 ft to the left when doing the stereo phase test...you should be perfectly centered between the 2 speakers, as Q has probably already mentioned to you...then adjust the toe-ins on both speakers appropriately.
This would probably be a better indication for you if you have a true phase problem, or if the odd speaker placement is the culprit here.

Most of us have to live with some compromises in our systems, I wouldn't worry too much about this, especialy for 5.1 playback. Sit back and enjoy!

Sir Terrence the Terrible
04-07-2005, 10:29 AM
I had this same problem when calibrating my setup. All of my wiring was correct as I checked it several times. But when I went to check the phase matching of all the speakers, I found my center was out of phase with my mains(and this is after checking the connections again). I just reverse the wires on the center, and the result was a tighter more coherent front soundfield, with excellent phantom imaging between speakers. I also got much better bass definition between channels(my center is set to large). Run the test again, if it still says your speakers are out of phase, switch the wire on the speaker that is lit up on the test. I am willing to bet that it will sound better to your ears if that is the problem.