Centre channel speaker sounds off-centre???

[s162216]

Hi,

After using my HT yesterday I noticed that the sound coming from the centre speaker didn't seem quite right. It seems to be focused more towards the left of the speaker than in the centre and and upon listening carefully when playing several sources through it, the left mid driver sounds (to me) a bit louder than the right. I've not even moved any of my speakers or altered any settings on my receiver (apart from volume) for at least the past 3 weeks and its been fine so does anyone have any suggestions as to whats suddenly causing the problem?

I'm connecting using coax for my DVD player and optical with my PVR and both of them seem to have the same issue even if sending a mono source to all speakers. Could one of the drivers suddenly started failing or something? (Hope not, already had an LCD TV backlight and a DVD player fail completely without warning this year)

 

[Pyrrho]

Yes, it could be that one of the drivers has failed, or it could be a bad connection to one of the drivers. You would still get sound from it in the cabinet even if it is not actually working, as the back pressure from the other woofer would cause it to move back and forth, even if it were disconnected completely. If it is not in warranty anymore, and if you are handy, you might want to remove the right woofer and hook it up directly to your receiver, and see if you get sound from it. (If either it is in warranty, or you are not handy, do not remove the woofer, and just take the center speaker to an authorized service center.)

Obviously, when connecting or disconnecting anything, the power should be off to it all, and with the woofer out on its own, the volume should be kept low.

If you don't get any sound out of it, but do with another speaker (either whole or just an individual driver), then your driver is bad and should be replaced. If you do get sound from it, reinstall it in its cabinet, and make sure all the connections are good. If you still have the problem at that point, remove both woofers and switch which one is on the right and which is on the left. If the problem switches sides, then there is a problem with the woofer, though it is still functioning (you replaced it with a new one if it did not work when out on its own). If the problem does not switch sides, there is a problem in the crossover, most likely a bad connection.

But before going on, let us know what the results are of this testing and examination so far.

 

[s162216]

Theres only one way of getting Tannoy stuff serviced in the UK, through them and unfortunately the speaker is now out of warranty as they give 5 years for passive parts and a year for electronics (assuming that includes the driver as well?). To send it to them would cost quite a bit as it weighs about 5kg.

Usually I would be able to take it to bits and do all the testing etc on the driver but I'm at university so I don't have my tools, soldering iron, meter, oscilloscope etc with me. I assume the driver would be within 8 - 16 ohms with them wired in parallel as my receiver only accepts speakers within those impedances.

Its really annoying as I've spent ages getting everything precisely right in my HT and then this happens. My HT sounds no where near as good with the centre at the moment and only a bit better without it as I'm so used to it.

Not so sure what to do now, I've been able to find new replacements for it but their about twice the price that I originally paid for mine.

EDIT: Just noticed a barely used one on ebay ending in a couple of day with no bids so far so I might be able to get that but the postage is a fortune (£20!)

 

[TLS Guy]

Theres only one way of getting Tannoy stuff serviced in the UK, through them and unfortunately the speaker is now out of warranty as they give 5 years for passive parts and a year for electronics (assuming that includes the driver as well?). To send it to them would cost quite a bit as it weighs about 5kg.

Usually I would be able to take it to bits and do all the testing etc on the driver but I'm at university so I don't have my tools, soldering iron, meter, oscilloscope etc with me. I assume the driver would be within 8 - 16 ohms with them wired in parallel as my receiver only accepts speakers within those impedances.

Its really annoying as I've spent ages getting everything precisely right in my HT and then this happens. My HT sounds no where near as good with the centre at the moment and only a bit better without it as I'm so used to it.

Not so sure what to do now, I've been able to find new replacements for it but their about twice the price that I originally paid for mine.

EDIT: Just noticed a barely used one on ebay ending in a couple of day with no bids so far so I might be able to get that but the postage is a fortune (£20!)

It's more likely to be your receiver than the speakers. Switch the left and right speakers, and see if the problem switches to the other side. If does not it is the speaker, if it does it is the receiver.

 

[Pyrrho]

Theres only one way of getting Tannoy stuff serviced in the UK, through them and unfortunately the speaker is now out of warranty as they give 5 years for passive parts and a year for electronics (assuming that includes the driver as well?). To send it to them would cost quite a bit as it weighs about 5kg.

Usually I would be able to take it to bits and do all the testing etc on the driver but I'm at university so I don't have my tools, soldering iron, meter, oscilloscope etc with me. I assume the driver would be within 8 - 16 ohms with them wired in parallel as my receiver only accepts speakers within those impedances.

Its really annoying as I've spent ages getting everything precisely right in my HT and then this happens. My HT sounds no where near as good with the centre at the moment and only a bit better without it as I'm so used to it.

Not so sure what to do now, I've been able to find new replacements for it but their about twice the price that I originally paid for mine.

EDIT: Just noticed a barely used one on ebay ending in a couple of day with no bids so far so I might be able to get that but the postage is a fortune (£20!)

For the testing I have suggested, there is no need for special gear at all. A screwdriver (unless something other than screws holds the woofers in place) and some speaker wire are all that is required. I think that there is a very good chance that it is a poor connection, and just disconnecting and reconnecting the wires to that driver within the speaker might fix your problem. Of course, if it is the woofer itself, then you will need to get a new woofer (or have that one rebuilt, though it may be cheaper to just replace it).

 

[s162216]

The drivers are held in using screws with a hexagonal head, I've got no screwdrivers that will fit them so I'll have to get one from somewhere to fit them.

I'll have a go with swapping the speakers before I go on and take the drivers out but I don't see how the receiver could be affecting it as its just a + and - wire terminal for the centre on it and using the receiver in 2 channel mode seems to work like there is a 'phantom centre', just not quite as good the actual centre.

 

[TLS Guy]

The drivers are held in using screws with a hexagonal head, I've got no screwdrivers that will fit them so I'll have to get one from somewhere to fit them.

I'll have a go with swapping the speakers before I go on and take the drivers out but I don't see how the receiver could be affecting it as its just a + and - wire terminal for the centre on it and using the receiver in 2 channel mode seems to work like there is a 'phantom centre', just not quite as good the actual centre.

The receiver can easily cause this and most likely is.

All it takes is one bad voltage regulator, or IC and you have your problem.

Before you take one screw driver to you speakers, switch you speakers to the opposite channel, then you will know for sure if it is the receiver or speaker. From experience, my money is on the receiver being the problem.

 

[highfigh]

Before you remove anything or spend any money. look at the speaker setup. If you set the distance from the speakers to your primary listening position, the left speaker is probably more in synch with the center channel than the right speaker. This would only apply if you're playing through all three of the front speakers, though. This could also be caused by one speaker being mis-wired, so the positive wire is on the negative terminal.

If the center speaker is the only one on and it sounds more to the left and it's an MTM configuration, it may be a bad driver or a loose connection.

 

[s162216]

Using Dolby Pro Logic II Movie mode on a mono source just sends everything to the centre and nothing to the LR's so I tried that. When the sound is purely coming out of the centre it still seems to shifted more towards the left so I think that's counted out any phase issues causing the problem.

Sending the mono sound to all speakers using PLII Music and switching the centre and the left speaker channel does not seem to make any difference so it seems more likely to be the speaker than the receiver now.

 

[markw]

Try the simple stuff first.

Turn the center channel upside down and turn the front right/left speakers all the way down. Does the problem switch sides? IF so, it could be one of the two drivers in the cabinet is wonky.

 

[s162216]

No it doesn't switch sides which I find odd. The LR channels were completely turned off with just the upside down centre but the sound still seemed very focused on the left and centre rather than uniformly across the speaker.

Any other suggestions anyone? I don't understand why its suddenly doing this after it being absolutely fine for weeks with me making no adjustments.

 

[ParadigmDawg]

Try cleaning out your left ear...

 

[HexOmega]

If your center channel is a MTM design and flipping it upside down made no difference, then I have to agree that we need a new acronym for the issue.

PEBSAC = Problem exists between speaker and chair

 

[TLS Guy]

No it doesn't switch sides which I find odd. The LR channels were completely turned off with just the upside down centre but the sound still seemed very focused on the left and centre rather than uniformly across the speaker.

Any other suggestions anyone? I don't understand why its suddenly doing this after it being absolutely fine for weeks with me making no adjustments.

If only the center is playing, there has to be something wrong with your right ear. There is no other explanation.

Good luck with the NHS. (No Health Service).

 

[s162216]

I remember now that about 6 days ago I moved the TV back a bit by accident so that it was practically against the wall (not the speaker this is on top of my old CRT as the backlight failed on my LCD). The problem seems slightly better now that I've moved the TV (and centre) forward a couple of centimetres. The sound on the right actually seems much better now there seems to be much more sound between the centre and the right, previously the sound seemed like it was coming out of the TV on the left and centre and hardly at all on the right. Its not quite good as it was before but after a few more adjustments I should have it done.

I assume the problem is caused by the sound being reverberated off the walls or something.

BTW TLS Guy, don't insult the NHS, I have 2 long term medical conditions (Type 1 Diabetes and Common Variable Immunodeficiency) and all the continuing care that it gives me is of excellent quality. I would much rather that the NHS pays for and administers the intravenous immunoglobin for the CVID than I pay approximately £1350 every 3 weeks (with the NHS drugs discount its actually costs the taxpayer about £700) and prevent me from getting ill as I don't naturally produce enough/any antibodies in any of the 3 major classes.

 

[s162216]

After much tweaking and adjusting I seem to have solved the problem, the entire centre sounds right again and the sound seems like its coming out of the TV once more. It must have just been me moving the TV back a bit accidentally and caused the sound to reverberate off the wall or something and then making the problem worst by me moving the centre and changing the distance setting in the receiver to try to correct it. (either that or I lost some of my hearing in my right ear for a while! )

Thanks for all the help guys