Beolab 5... Inverted phase?

Hello,

I have owned the bl5 for many months already, but because the speakers have been sounding wonderfully to my ears, only recently I did try to run audyssey-pro calibration system.

By surprise, Audyssey detected and warned that one speaker is out of phase.

Does anyone know whether the beolab 5 have been designed that way?

Thank you

Maab:

I have owned the bl5 for many months already, but because the speakers have been sounding wonderfully to my ears, only recently I did try to run audyssey-pro calibration system.

By surprise, Audyssey detected and warned that one speaker is out of phase.

Does anyone know whether the beolab 5 have been designed that way?

 

Hi,

I guarantee that your two BeoLab 5's will have the same polarity, meaning that positive-going voltages at the inputs will result in matched excursion directions of the drivers.

However, the phase of the two loudspeakers at any given frequency could be different, depending on things like the distance from each speaker to your measurement microphone, different ABC filters in the two loudspeakers due to different placements in the listening room, or a host of other reasons.

If the Audyssey system is telling you that your phase responses aren't identical, this should not come as a surprise (unless you measure one loudspeaker in a location, then replace it with the other speaker and compare the results with the two speakers in identical positions in the room - and even then, this will not result in perfectly matched phase responses up to 20 kHz).

Since you're using the Audyssey system, then I assume that you don't have a fully-B&O system. Are you using the line inputs of the speakers? If yes, (and if the measurement is telling you that you have opposite polarities) then are you certain that your cables are matched? It is possible to make a line input cable that flips the polarity.

One other question: do your speakers sound like they're opposite polarity? If you're getting a stable phantom centre and no shortage of bass, then I would start by questioning the results of the measurement rather than the speakers...

Cheers

-geoff

Thank you very much for your detailed reply. 

Interestingly, as you mentioned the cables, I have two completely different cables -different brand and different length (8ft and 27ft).

I never thought about that. 

Soon as I get a matching pair I will test audyssey once more. 

As it is now they sound fine but it's hard to compare. 

I'll post back...

Thanks again.

 

Maab:

Interestingly, as you mentioned the cables, I have two completely different cables -different brand and different length (8ft and 27ft).

 

One quick option is to swap the cables and see if the "wrong phase" measurement follows the cable or stays with the speaker.

Cheers

-geoff

geoffmartin:

One quick option is to swap the cables and see if the "wrong phase" measurement follows the cable or stays with the speaker.

Cheers

-geoff

I replaced the cable and run audyssey.

But last night I got the out of phase message again, for the right speaker. When I have the chance I will swap the speakers and see what happens.

Thank you.

M

geoffmartin:

One quick option is to swap the cables and see if the "wrong phase" measurement follows the cable or stays with the speaker.

Cheers

-geoff

Geoff,

Do you by the chance know how to reset the bass calibration to factory?

Thanks again.

M

Maab:

geoffmartin:

 

One quick option is to swap the cables and see if the "wrong phase" measurement follows the cable or stays with the speaker.

 

Cheers

 

-geoff

 

 

 

Geoff,

 

Do you by the chance know how to reset the bass calibration to factory?

 

Thanks again.

 

M

1. Turn the speaker off

2. Put your hand on the top as when calibrating them, and keep it there.

3. The speaker will start calibrating for a few seconds before shutting itself off

4. When turned on again the green light will flash signalling that the speaker is not calibrated

Tompasten:

1. Turn the speaker off

2. Put your hand on the top as when calibrating them, and keep it there.

3. The speaker will start calibrating for a few seconds before shutting itself off

4. When turned on again the green light will flash signalling that the speaker is not calibrated

Thank you very very much!