Axiom Home Page Forums General Discussion Home Theater Sibilance

Gentlemen,

I've had my Axiom setup for a few years now (Epic 60-500), mated with Outlaw equipment (990/7125), Oppo DVD player and a Motorola 6412 cable box (Shaw Cable). Over this time I've thoroughly enjoyed my system, primarily watching cable television and movies, with some occasional music.

However, for some time now, I've come to notice quite a bit of sibilance from dialog, particularly watching cable television. I recognize that cable recordings aren't always great but it seems that I notice the sibilance on a wide variety of cable programming and also notice it when watching DVDs. I notice it less with music (which I listen to in Dolby Prologic II, utilizing my center channel).

Are there any methods by which I can try and reduce or eliminate some of this sibilance? I'm starting to fixate on it, particulary watching cable, and it is becoming somewhat annoying.

My receiver does have a 'Theater Compensation' setting which basically rolls off the high frequency range. I have tried this and it does help somewhat, but it tends to deaden the overall sound quality which I don't prefer. I do prefer the detail that my system provides but I'd like to reduce the sibilance. The sshhs and ttthhhs are driving me a bit nuts!

Any thoughts or advice? Any help is appreciated.

Thanks!

Bryan

I find msny TV shows, especially old or cheaply produced ones, are poorly recorded and come with a lot of sibilance built into them. Your M60s are extremely accurate so if there is sibilance in the soundtrack, it will 'accurately' reporduce it for your ears. Newer shows, especially big budget and HD shows are getting better. Kind of like when you buy your first big screen, HD TV expecting a better picture for all but it's size actually makes old or poorly produced shows look worse than your old cheap 22 incher. Like a big screen HD TV, it only shines when it receives a quality source and can be much less forgiving to crappy sources.

If some shows and DVDs are not producing any sibilance at all, it is very likely that it is just the speakers doing what they do best. Bringing out every detail of a sound track, accurately.

Of course this doesn't answer your question on how to reduce it, irregardless of where it comes from. I'm afraid I don't have much advice there. Playing with tone controls and other settings may help but the only consistant way to remove sibilance on a quality, working system is to not feed it any in the first place.

Others may have better advice on compensating for what is already there.

Hi icehawk21,

That does seem odd that you are noticing the sibilance mainly on TV and DVDs. While the M60s are detailed speakers, they do not have an exaggerated upper midrange or peak in that region that would emphasize sibilance. I hate the latter, and Lord knows, it's all too common on lots of CDs, partly because some recording engineers use a "presence" boost in that region so vocals will seem clearer when broadcast on radio (FM or AM) or heard on other media where losses occur. There are plenty of microphones that have a switchable "presence" emphasis that some singers and engineers like. When you hear those reproduced on an accurate linear system, the sibilance can drive you crazy.

When I do listening tests for Axiom, I'm especially sensitized to any trace of excessive siblilance that I believe to be inherent in the speaker. Some of the CDs we use do have traces of built-in EQ'd sibilance, for example, the highly praised live concert CD of the Eagles, "Hell Freezes Over" has a trace of vocal sibilance on the recording, which I allow for. So do some of Holly Cole's CDs and those of the BareNaked Ladies. For myself, I use some vocals that have no trace of artificial sibilance, so if I hear any, I know it's the result of a frequency response aberration in the speaker.

In your case, my suspicions are on the Shaw Cable feed via the Motorola box. As cable operators try and shove more and more HD and SD programming, Video on demand, internet and telephone services down the cable line, they are using more and more compression in order to lessen the bandwidth demands of the combined services. One of the side effects of too much compression can be an edgy sibilance on vocals and dialog.

You might try contacting the chief engineer of the Shaw system locally and find out if any of the compression algorithms might cause this.

As you discovered, the Theater Compensation setting isn't a great fix; you also try reducing the treble control a bit, but it's almost impossible to lessen the frequency range where sibilance occurs without also reducing the detail, which you like.

How are you feeding the audio from the Motorola cable box to your system? You might try the analogleft and right audio connections from the cable box (if it has them) to see if there is any reduction of sibilance in the TV programming.

I'd also turn off any auto-EQ like Audyssey that you might be using. Those tend to be error-prone and might be applying a boost in the dialog presence region.

Regards,

Alan

See by flaunting my lack of knowledge, it creates a bat signal for Alan to come to the rescue.

You can thank me later.

My AVR has the option to roll off the highs as well (which I do not use either). However if you find this helps for those sources where sibilance is an issue, can you save different presets in your AVR? That way you can just flip to the desired preset depending on the source material. More of a bandaid than a solution I'll admit, but that's all I can think of.

You could just try the old fashion method... whack your speakers a few times and see if that helps.

Murph, much of what you said is totally accurate.

Alan

Hi Icehawk21,

I can't help but ask if you run TV in stereo mode as these guys believe you are with M60s. I personally would assume you run Pro Logic/II on TV material so you are using the VP150 center for dialog correct? Interesting, they would seem to be playing dumb talking about your M60s when the problem is the VP150.

Here is a question for you Alan. Considering your extensive experience and testing of the Axiom product, have you not noticed "sibilance" on dialog with the VP150? I'm also curious why you'd go on to talk about the M60s when he's clearly talking about the VP150...

Solid-State

PS IMHO the driver layout for the VP150 makes it great for very near-field listening (2-4 feet)) or if your way back 15 plus feet. If your at the distance as is typical for home theater your a victim of all kinds of combing and off horizontal axis artifacts and these manifest as sshhs and ttthhhs. Alan have you not noticed this in your extensive listening tests?

By the way icehawk I have the EXACT SAME EXPERIENCE and it also was driving my uncle and me nuts. The solution was to use phantom center temporarily and replace the VP150. The better solution would be for Ian and the others from Axiom to actually design a new center. Heck outside of the outdoor speakers and that, no comment, dual sub woofer monstrosity, you guys haven't designed a new speaker for almost a decade!

Perhaps it's time to accept the design flaws on the VP150 and go back to the drawing board ehh!

Solid-State

I thought he said he was finally going away.