white noise test ??? (1 Viewer)

[JoeyS]

the white or pink noise test from my sony 945 receiver sounds "different" between my 2 fronts and my centre channel,they are different speakers (vegas for the fronts and axioms for the center) is this normal?

even more odd is the two rear speakers sound like a different tones from the right and the left and they are both identical speakers (axiom q8's) is this normal?, could they be defective they sound great when they are on !!!

 

[John Garcia]

Yes, I would say with the difference in the speaker designs and driver materials, that it is "normal" for them to sound different.

The rears should sound identical, so I would suspect something is wrong. Listen closely to the speakers with the volume down, with music, to see if the tweeter is damaged on one or the other. Also try swapping them to see if the different sound follows one of the speakers. If you cranked them up to the point of distortion, it is very easy to destroy a tweeter, especially with an underpowered receiver.

 

[Bob McElfresh]

First, I doubt your speakers are broken.

Have you level-adjusted the rear volume with an SPL meter? That's what the test-tones are for - simple volume adjustment. The 'difference' in sound you hear could be just volume. You really need to use the $40 Radio Shack SPL meter first to check for equal volume at your listening position.

Check the angle the 2 rear speakers are using. If one is pointed differently, this can cause an apparent difference. A cheap laser-pointer is a nice tool to "see" where the speaker is pointing.

Does one of your rear speakers have a wall/furniture near it that is not symetrical with the other? Reflections from nearby surfaces can cause this.

Hope this helps.

 

[ColinM]

I also have identical surrounds, placed in very different ways. One is wall mounted and firing out of a corner, the other is placed on a bar counter, basically in free space, no walls.

The one in the corner is -4db from the other to be balanced, and pink noise does sound different.

 

[Blake R]

I get a better timbre match between my AR mains and my infinity rears than I do between my AR mains and my AR center channel from the same line. Speakers, as they say in engineering, are funky.

 

[Bob McElfresh]

the other is placed on a bar counter, basically in free space, no walls.

Well this explains it.

Your speakers really do radiate sound out the back/sides. On the corner-mounted speaker you get lots of quick reflections from the nearby walls. On the bar-mounted speaker you get none.

If the bar speaker is pushed back, the shelf in front is also reflecting some of the sound upwards causing a bit of distortion. My guess is that the bar speaker is vibrating a bit while the corner-mounted unit is firmly attached/dampened.

While you have 2 identical rear speakers, you have 2 very different mountings/surfaces. This is a lot like having 2 different speakers.

Unless you can symetrically install the rear speakers with respect to your listening position - they are going to sound different.

Is this a major problem? No.

The rear speakers mainly carry effects. Not dialog, not critical music. So you can get away with it. And many modern movies send different sounds to each rear speaker. So it's fine to have them be a bit different. (If these were the L/R speakers in a music system - different story). As long as you have volume adjusted the rears with a SPL meter you should still get a great HT experience.

Hope this helps.

 

[ColinM]

I'm not the one with the problem... Although it may sound like an issue, it's just rear fx, no biggie to me. And I have no other alternative so I don't even think about it.
I just wanted him to know he's not alone.
And I use tack on anything standing on a surface - highly recommended.