Unbalanced BL8002 in Masterlinked BS9000 system

Hi,

I have a BS9000, BL8002 & BV6-26 in a master-linked system and I have an issue with the sound being unbalanced when music is played through the BS9000:

Through the TV (speaker 2), sound is balanced between the 2 speakers, but when a CD is played it is more towards the right-side speaker. My initial thought was speaker issue so I swapped the speakers round but same result, I then plugged the speakers directly into the BS9000 and sound is perfectly balanced left/right. So I'm thinking the issue must be TV based?, or a masterlink cable issue (as this is the only thing that links the TV to the stereo)?

The sound setting (via the TV) are all set at the mid-points, both speakers are set as 'wall' and are equal distance from the TV and viewing/listening position.

Has anybody had a similar issue, or ideas what the fault could be?

Many thanks

Ian

Ian,

Masterlink is distributed around the house in a Balanced Audio format. If one channel has one "leg" disconnected then that channel will pick up a signal between the good connection and earth with a 6db reduction in audio level. This will make one channel 6db (or 2x) stronger than the other.

Check continuity on the Masterlink connections.

Ron

Have a very similar issue, though mine is a little compounded by NL/ML converter in the middle.

BS9000 with BL8000 directly connected, no balance issues.

BS9000 > ML > ML//NL Converter > NL > BV11 with BL9 connected, right speaker distinctly louder than left (if on BV11 I adjust volume of left by +6db it seems balanced).

I took out my multimeter and checked the ML cable between BS9000 and ML/NL converter, all connections fine (was thinking one of the Orange/White or Orange would be a problem since it's the left channel). 

So a little stumped...  No issue with ML cable and I presume from NL/ML Converterr it's all IP? So nothing there?

Any ideas?

 

The problem appears to be with the Masterlink set up. As explained before a 6db loss in one channel can be caused by an unbalancing of the channel by one leg of the circuit becoming disconnected. It can also have the same effect if one leg is short circuit to earth. Check the faulty channel for resistance to earth of both legs, they should be the same.

Ron

Ron,

This was exactly my issue - Checked the connections in one of the junction boxes and 2 cables had broken loose, now repaired and normal balance is restored. Thank you so much for your help, much appreciated.

Ian

langleyav:

The problem appears to be with the Masterlink set up. As explained before a 6db loss in one channel can be caused by an unbalancing of the channel by one leg of the circuit becoming disconnected. It can also have the same effect if one leg is short circuit to earth. Check the faulty channel for resistance to earth of both legs, they should be the same.

Ron

Thanks Langleyav, quite frustrating - I disconnected all the Masterlink plugs (BS9000, NL/ML Converter and BL3500) and checked each one individually for a short circuit to earth (checked all circuits, left, right, data etc.) not a single indication of a short circuit / bleeding. I did the same thing at the junction box, even went as far as checking each circuit against every other circuit. Nothing whatsoever - the cabling is sound. I checked all the plugs to make sure that one of them don't have the wrong wire connected to the wrong pin etc. (thinking maybe one of the plugs the + and - got switched..) but nope.

Can it be the Masterlink connector on one of the components (BS9000, BL3500, NL/ML converter?) how would I be able to test that? I did disconnect the BL3500 and had the problem on the BV11 connected via ML/NL so I suppose I can rule out the 3500. Perhaps I should leave the NL/ML disconnected and do direct BS9000 to BL3500 and if that's fine I can conclusively say problem is with NL/ML converter or if not then it points to BL9000?

Any ideas?

Also what should the normal resistance be with the masterlinks plugged in? When I left the masterlink on the BS9000 plugged in, I could see that there was a current flowing between the left/right circuits (individually) and some of the other circuits.

berlin2010:

 Perhaps I should leave the NL/ML disconnected and do direct BS9000 to BL3500 and if that's fine I can conclusively say problem is with NL/ML converter or if not then it points to BL9000?

 

That`s exactly what I would do in the next step. If the issue still exists I`d try another ML cable...

Stefan

So, disconnected the NL/ML converter and did a direct connection between BS9000 and BL3500....  And the left channel is still softer than right. Clearly not as a obvious as with BL9's - suppose having the speakers 3 meters apart (BL9's) instead of next to each other in the same enclosure (BL3500) does add to the stereo imaging.

So now am definitely thinking it is BS9000 that is somehow faulty on the ML connection. Anyone had anything like this before?

Just a quick update - I did eventually get to the bottom of this. Turns out that two of the pins on the Masterlink Connection in the BS9000 were bent... The BS9000 is wall mounted and I can only imagine that in the fiddling behind it when I inserted the Masterlink cable (very close to wall with little space to work) i must've wedged in the Masterlink cable at an angle and so bent the pins - you can see the pins in photo below, the bent ones are the 3rd and 4th pins from the right (which so happens to be the Left Audio cables). 

 

 

Apart from being quite tough to get an "instrument" that will go into the connector given the enclosed space to work in, fixing it was a simple matter of bending the pins outwards again. All's well now