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Troubleshooting a ‘Strange Sounding’ Speaker

Al Griffin  |  Apr 7, 2016

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Q I’m wondering if my center speaker is damaged. When I watch movies with 5.1 soundtracks, voices sometimes sound strange, as if the actor is speaking with a lisp. I seem to hear it most with movies streamed from Netflix, and occasionally on cable movie channels like HBO. Do you know of any test DVDs or other material I can use to evaluate my system and speaker set up? —Craig A. Childress / Lake Charles, LA

A You can find a few calibration DVDs with audio tests for $10 or less at Amazon.com, including Disney Wow: World of Wonder and Digital Video Essentials. If you own a Blu-ray player, you can find Blu-ray versions, along with the AIX Audio Calibration Blu-ray for $24.99 at oppodigital.com. Each of these discs provides test tones to ID speaker assignments in a multichannel system, plus phase tests to confirm that the positive and negative terminals on each speaker are wired correctly. In addition, many THX-certified DVDs and Blu-rays include a THX Optimizer supplement with similar content that allows you to perform the same tests.

I should add that while the above discs can verify that your center speaker is both active and in phase with the left/right channels, the test suites they provide aren’t comprehensive enough to confirm that it’s in perfect working order. Short of sending the speaker out for repair, your best bet will be to watch a DVD with a dialogue-heavy soundtrack. If voices coming out of the center channel sound muffled or distorted, the problem is likely to be with the speaker and not with your streaming and cable TV services. I’d also recommend temporarily swapping the left and center speakers. If the problem moves, the speaker is defective. If the problem stays in the center location, the speakers are probably fine and there are other issues.

COMMENTS
mikem's picture
Submitted by mikem on April 7, 2016 - 12:06pm

The other culprit in this could be poor streaming. Also, I've viewed plenty of BD's and the sound design was pitiful, especially the center channel. I'd suggest playing some music heavy on vocals. For testing I'd also suggest some DTS-MA either 7.1 or 5.1. You can find lots of these on ebay. Lastly, I had a poor sounding LS surround that was bugging the heck out of me. I would have bet the house that I had hooked all speakers up correctly - but lo and behold the LS was hooked up incorrectly. I dreaded having to pull my receiver out, but since I knew it was the connection I simply unscrewed the speakers out and switched the polarity that way. One other thing does the center channel give you problems with un-streamed tv?

Ednmod's picture
Submitted by Ednmod on April 16, 2016 - 6:59am

I had a similiar problem, I have the PSB Image line and whether it was watching a blu-ray, live sports, or music in 5.1 the voice sounded unclear with no highs to it and muffled from the center channel speaker. I realized I had a damaged tweeter. This could be tested by removing the tweeter from the speaker and connect the 2 electodes to a AA battery. When you make the connection you should here a clicking noise. When I did it the noise was very soft so I bought another tweeter for my Image center channel speaker(PSB still had my tweeter even though the set is about 13 or 14 years old). It made all the difference in the world, everything was clear, with the high sounds back.

Hope this helps,

Ed

KINGTED's picture
Submitted by KINGTED on April 21, 2016 - 3:50am

Does it sound like sibilant distortion coming from (mostly) the center speaker? I had a similar issue with Netflix 5.1, and I use phantom center channel. After experimenting with multiple sources and some online research I found that my Denon receiver had an issue decoding Dolby Digital Plus, which Netflix uses for 5.1 and I believe HBO Go does too.

If you have a receiver that has upgradable firmware, try that. Your other options are to force Netflix into 2 channel mode and use Dolby Pro Logic or a similar surround processing, or add another processor into your system. My receiver was older and lacked upgradable firmware so ultimately I added a separate preamp that I already had laying around into the mix. It isnt ideal but I am looking to move to a third option, upgrade to a Atmos/DTS-X systems in the not too distant future.

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