Axiom Home Page Forums General Discussion Stereo sibilance

It was worth a shot. Sorry it didn't help.

Hi asher770,

"Sibilance"--exaggerated "sss" and "ttt" sound--is often heard on FM broadcasts, the result of microphones that have a peaked "presence" effect in the upper midrange, for intelligibility of the announcer's voice heard on lower-fidelity gear (car systems, tiny radios, boomboxes, etc.). The upper-midrange peak is inherent in the microphone design, or sometimes added with a touch of EQ by the radio station engineer. Linear speakers like the M80s, M60s, etc. will reveal sibilance in the source material, whether it's FM or CDs.

You would never hear it on AR speakers, which historically have had very depressed upper midrange and treble. In tests of AR speakers, including models I owned (AR3s, AR2ax's), the treble and upper octave response was down by 10 dB! That's equivalent to turning a treble tone control fully down (counter clockwise).

Many pop and rock recordings (some classical and jazz) are also EQ'd in the mids (again for radio airplay), so they may be sibilant played on linear speakers. As an example of this, I once spoke to a Canadian jazz singer, Holly Cole, about the microphone she used for live performances (and a similar one for some of her recordings). It had a pronounced midrange presence peak that made her concerts really irritating, with sss and tt sounds that could take your ears off. At a Toronto reception after a concert, I politely mentioned the subject, and she seemed to appreciate my comments. Whether she changed mikes for later concerts I don't know. Some of her later CDs do not have the sibilance that earlier discs had, so perhaps my remarks influenced her.

Anyway, use your tone controls to tame annoying FM broadcasts or CDs that have excessive inherent siblilance. Often a 2-or 3-dB reduction in the treble will make it quite listenable.

As to "depth," lots of rock or pop recordings don't have any. They are entirely artificial studio creations so you will get a flat soundstage. They are multi-miked and digital reverberance is sometimes added to make them a little less dry-sounding.

On the other hand, if you play some recordings that are simply miked (concert classical or jazz done in a live venue), the M80s should reproduce that sense of depth quite realistically.

Regars,

Sibilant or not, Holly Cole has an excellent voice.

Hi alan, Regarding the AR9 speakers that I used in my test for sibilance,they are not the vintage AR9's.They are one of the last speakers AR produced before going defunct a year ago.Their published frequency response is 32hz-22khz +-2db's.Listening to them I find that they are not as detailed (bright) as the m80's but they are certainly not lacking in highs.I to used to own the AR2ax speakers so I understand where your coming from , however the AR9 is a different breed.

Hi asher,

Were those the tall towers with side-firing woofers? I'd have to dig into some of my files. I know that long after the original AR folks left (Ed Villchur, Henry Kloss, Roy Allison), AR did hire some new designers and produced serveral speakers that were not the like old ARs, with the depressed mid and treble response. One of those engineers, Ken Kantor, went on to found his own company, NHT. I do recall hearing a very good AR speaker that he'd designed but I can't recall the model. It was floorstanding and tall.

Regards,

Hi Alan, Yes they are the ones with the side firing woofers.They happen to be fantastic sounding speakers but highly underrated by the high end crowd for reasons beyond my comrehension.I prefer the m80's because of the grearer detail,but thats a matter of personal taste.I am very reluctant to get rid of them,but am getting to much flack from my better half and will have to do so. Best regards. Asher

P.S. to the above .The AR9 as well as the m80 happen to be much better speakers then the some of the "high end" junk being peddled at exhorbetent prices to some gullible people out there.I really think that most reviewers in the so called high end publications are either deaf or on the payroll of some of the "high end" companies.

I had a pair of ARs in the early 80s but cant remember which ones they were. After a long web search last night I still cant find them.
Does anyone know of an AR data base?
Just curious.

I found them. They were AR58bxi. First good speakers I ever owned.

I haven't seen any discussion about trying to use felt for reducing brightness so I'd like to bring it up. First an intro:

Setup:
I have experience with the M60's for about half a year now. My listening setup is for stereo only. The integrated amp is a Musical Fidelity A308, and the source is a Sony CDP-CX455 changer. It's setup in a loft-style apartment with high ceiling and bare hardwood floors (rather reflective conditions). I’ve experimented with placement and the best results seem to be with the speakers about 7' apart, 1' from the rear wall, no toe-in. Listening position is about 8' from speakers.

A bit too bright:
Although I like the lively, dynamic and detailed presentation of the M60's, they sound a bit too bright causing ear fatigue after half hour or so. I only use original CD's (no burned cds, mp3's, ...) and the music is mostly rock, not at very high volumes. The sibilance is noticeable with the 'sssss'. For example, I consider Morrissey's 'You are the quarry' a well mixed album but still the s’ can have a metallic shrill to them. On my other setup using Mission 773e speakers there is no hint of sibilance (they have silk dome tweeters, granted).

Resistors:
I read on this board about using resistors to try and tame the highs so I called Joe and was promptly sent a 2.7 Ohm pair. After having them for a month or so they had to come out. It did tame the highs but the sound lost too much of it’s sparkle, and although it reduced, did not completely remove the bright/metallic s’. The problem is that the resistors equally lower the entire frequency range of the tweeter, thus reducing upper midrange clarity which I’m sure the folks at Axiom worked hard to achieve. After another month, I again couldn’t deal with the brightness and thought that a lower resistor value was more appropriate. I went to Fry’s and bought a pair of 10 W, 1.5 Ohm resistors for $1 or so, similar looking to the ones I got from Axiom. I have an LCR meter at work and tested them, and they were well matched to less than 1%. For the M60’s, the 1.5 Ohm value is a lot more appropriate than the 2.7 Ohm in terms of balancing reduction of tweeter glare and not muting too much the upper mids. Still, the ‘ssss’ can be fatigue-inducing at times. I wish there was a way to tone down the sibilance without muting the upper mids. Probably a better CD player and adding a carpet would help, but it’s not an option at this point. As a side-note, I read on another thread that Axiom started charging $30 for the resistors?! I hope that it’s not the case. They can be bought for far less and even if you include the price of the sliding contacts and shipping, I could understand $5, but $30? Axiom’s supposed to provide good value, right? Not wanting to sound negative, I do have to say that the presence of this forum as well as the excellent customer service speaks highly of Axiom.

Felt:
I recently came across an interesting board discussion about using felt around the tweeter to reduce the dispersion effects around the tweeter and was wondering if anyone’s tried it for their M60/80’s as a way to smooth the highs. Here’s the link:
http://www.soundandvisionmag.com/idealbb/view.asp?mode=viewtopic&topicID=31143&num=20&pageNo=1
This is very different from what some people on this board have tried:
http://www.axiomaudio.com/boards/showthreaded.php?Cat=&Board=HT&Number=70377&page=&view=&sb=&o=
I’d be curious to hear if anyone’s tried both the resistor and felt and how they feel about one vs. the other.