Sibilance: What Causes Harsh S Sounds and Can I De-Ess Them?

Sibilance: that harsh 's' sound that you hear when listening to music or audio. What causes it? Are there steps you can take to reduce it when you're listening to music?

Sibilance: What Causes Harsh S Sounds and Can I De-Ess Them?

We recently had an interesting question in response to one of our YouTube videos where, you know, I believe it was a customer but maybe not, asked the question about what causes these hard S's, these sharp S's and how can I get rid of it?

Now, you know, these hard sounds at high frequencies, we can say that that's, you know, it's spittiness or graininess or sometimes we'll call that sibilance which is actually a technical term that's part of speech and it's how hard our, you know, our S's, our S sounds.

Those are the things that typically people are talking about when there's hardness or edginess to S's. And this question was, you know, "How do we get rid of that or why am I getting it?" Now, a lot of times, if people change their speaker system, they'll complain that all of a sudden, you know, everything's sounding very spitty, very sibilant.

"And on my old speakers, it didn't sound that way." Well, you know, it's easy to blame the new speakers but at the end of the day, what's possibly happening is that your old speakers may be, particularly if they were quite old, they may have been out of specification at high frequencies. It happens particularly with tweeters that use ferrofluid.

After 10 or, you know, 20 years of use, that fluid tends to dry up a little bit and it'll gum up the motion of the tweeter which will drop its output level. So it's all a lot of...you know, it's a memory and understanding of what you've been living with and what you're used to and any time something changes, the way that you perceive things, the way that you hear things also will change until you, you know, get accustomed to the new sound.

So it's actually, in many cases, your new speakers, if you're finding them hard or harsh in the high frequencies, it could be simply that the new speaker's flatter and more neutral than your previous speakers. Now, one other thing. We love to blame equipment, we love to blame amplifiers and speakers and, you know, CD versus vinyl for sibilance or spittiness and hard S's.

But you know what? In my experience, 90 odd percent of the time, maybe even higher, when you hear those sorts of hardness, that sharpness in a piece of music, it's actually detrimental in the recording. It's, you know, either you're listening to a compressed mp3 which doesn't do those S sounds any favors at all, or just that the mastering was done, you know, with all the levels pumped up, with high compression and you get more energy in those S's.

There's more signal level actually compacted into that range if we compress the signal. And, you know, engineers happily equalize things as well. I mean, we want things to sound, you know, more punchy over ear buds, for instance, which a lot of people are listening on these days.

So they boost the treble. So there's all kinds of things that can be going on. So number one thing to check. Play a variety of music. If you put one song or one recording on and you say, "Oh, that's really sounding harsh." Try a couple of other recordings, a couple of other artists and see do you notice that same effect all the time on everything?

And I'm going to bet that in most cases, it's only certain cuts, or certain tracks, or certain albums where you're getting that hard S or that sibilant sound. Now, if that's not the case, if you actually are hearing that on the majority of music or even dialog that you're playing back on your system, there are a number of things that you can simply go through and check to try and see is something set up wrong or there are some placement things you can do with the speakers to mitigate that a little bit.

So the first thing is to check, absolutely check to see if you're using a home theater receiver or an AVR that if you've got auto EQ set, whether it's Odyssey or any of these other systems, try turning that off because in many cases, those auto EQ systems will actually mess up a good loudspeaker's amplitude response.

So it'll boost and cut in areas where that measurement microphone that you've placed around the room is telling the system that it should boost or cut, and in reality, maybe that that's not right. Maybe letting the speaker unequalize is going to give you better performance in your system. So try that. Look at that for a second.

 

 

If you've got an old-school integrated amplifier or receiver with tone controls, make sure that they're all set to the flat setting. Make sure, you know, somebody hasn't come in and turned everything up. I see that all the time, people with the bass and treble controls maxed out. That's definitely not going to help your hard S sounds and sibilance. The final thing regards placement.

If you're finding that, you know, those high frequencies are a little accentuated in your system and you have the speakers toed in so that they're pointing right at the listening position, try toeing them out a little bit. You may even find that having the two front left-right speakers firing straight ahead, even though, you know, it's counter intuitive, don't you want them firing at you?

Firing straight ahead the direct signal to where your listening position is is going to be reduced a little bit in high frequencies because you're a little bit off access or off to the side of the tweeter position. The other position that you can do is play with the overall balance. If you have a pair of bookshelf speakers and they're on stands, for instance, try moving them a little bit closer to the back wall.

That will bring up the mid-bass balance and sometimes, it's actually just a balancing act. There's not too much high frequency that's causing these hard S's, it's there's not enough low frequency and you want to balance them out. So sometimes, placement can help with that. But again, at the end of the day, 9 times out of 10, it's that the recording or the mastering just wasn't good.

And for sure, if you're listening to a compressed mp3, try to get an uncompressed version of the same album. In many, many cases, you'll see that that hard S sound and those sibilance that are driving you nuts are gone. Thanks a lot for reading or watching and thank you for continuing to comment on our videos and blogs.



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