DENON AVR- 1905 AV surround receiver centre speaker issue

[markymark2406]

I have a DENON AVR- 1905 AV surround receiver which I use to watch movie 5:1 Dolby it’s working fine with great sound but a problem exists with the centre speaker which is a YAHAHA MODEL NUMBER NS-C515 it’s really muffled as thou it’s got not treble (top) to the sound coming out.

I have altered the settings on the DENON receiver ie the bass and treble, changed volume and made sure the receiver is in cinema mode which it is.

Any help would be appreciated ??


thank you

 

[ninjacat]

Quick guess would be blown hi end speaker cone. pop the cover off the front and listen to all the cones - it appears to have two mids and a high in the centre.

Also, it can be bi wired so make sure the connections are solid at the back. There should be a link between the two positives and a link between the two negatives if running from a single amp

https://de.yamaha.com/files/download/other_assets/7/327427/NS-C515_GR_en.pdf

 

[markymark2406]

Ok I’ve just taken the cover off and first there is no sound coming through the centre speaker, that’s rated to 6ohm so will stick a meter on it tomorrow to see if it knackered. There is obviously a crossover circuit inside (pictures attached) what usually goes on these things ?

 

[markymark2406]

I guess the yellow resister or the brown cap ?

 

[Lucid]

Although it can't be ruled out, generally speaking, crossover components take a long time to fail unless the speaker has been abused in some way. There isn't the sort of heat levels inside a loudspeaker that you encounter in amps and other active devices, and so decent capacitors don't dry out as quick.

At a guess, I'd say that the centre speaker is roughly 20 years old. The big yellow component looks like a film capacitor. They last a long while. The small brown one could be an electrolytic. If so, then they that's the one that will have a shorter lifespan.

As @ninjacat suggests, check the speaker binding posts/banana plugs/HF-LF bridging links first if the speaker is bi-wired. After that, the most likely item to fail is the tweeter itself. A quick test with a 1.5v battery will tell you if the tweeter is duff. Set up a couple of wires off the battery terminals. Touch them on the speaker terminals very briefly. You'll hear a little click if the tweeter is good.