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Causes of "harsh" sound in speakers (and tweeter material)

thanossapiens

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One of my biggest issues when listening to different speakers is that a lot sound unbearably harsh(sibilant?) to me, even if they measure flat-ish on the treble. Sometimes its hard or impossible to EQ away for some reason, even if I know where the peak is. This made me think it might be some sort of sibilance, but looking at spectral decay plots (i dont know if these are the most relevant ones but im a newbie at this), while not perfect, a lot seem to be ok.
I noticed that the worst offenders are usually hard domes like diamond or beryllium tweeters. I'm not sure why, but I dont think its placebo since most of the time I got to hear super expensive stuff from B&W or Focal,etc I was thinking "I bet this is gonna sound amazing" and not the opposite.
Perhaps most recordings, even "audiophile" staples like Dire Straits are kinda bad and it shows more on good speakers?
I'd love to hear your thoughts if you have any, thanks
 
Sibilance is sometimes induced during the recording process. So with some songs you may get more or less and the speakers may not be to blame. Diamond or beryllium tweeters are not prone to sibilance unless the tuning of the speaker includes sibilance.
 
Not to kick off the whole B&W thing again, but the latest ones have some odd peaks in the treble.
 
I noticed that the worst offenders are usually hard domes like diamond or beryllium tweeters. I'm not sure why, but I dont think its placebo since most of the time I got to hear super expensive stuff from B&W or Focal,etc I was thinking "I bet this is gonna sound amazing" and not the opposite.
This is not very surprising. Expensive != good. B&W is known to be bright, here a diamond tweetered one:
1699297864022.jpeg

Focal usually does better, but of them those big expensive speakers also suffer from showroom sound: standout in the showroom, but once at home, it’s not very accurate.
 
Something else I have thought of is that maybe these tweeters can handle power a lot easier than their woofers, so at higher volumes there is elevated treble? I have no idea if that's a thing generally though.
On that note I also want to ask if "trails" in spectral decay plots imply sibilant sound or something else.
Uhm...those aren't necessarily examples of excellence.
Yeah I know, but seeing 6 figure price tags does have an effect I guess
 
Yeah I know, but seeing 6 figure price tags does have an effect I guess
On me it makes me demand measurements. It's a world of snake oil marketing. See graph above.
 
This is not very surprising. Expensive != good. B&W is known to be bright, here a diamond tweetered one:
I have the Yamaha NS-1000, and I can hear some harshness from them but I just dont see why. A way I would describe that is as if some peaks get +10db for a split second, if that makes any sense.
https://www.hifinews.com/content/yamaha-ns-1000m-loudspeakers-lab-report
On me it makes me demand measurements. It's a world of snake oil marketing. See graph above.
At this point thats what I think too. I remember being incredibly disappointed when I first went to a hi-fi show, I thought the giga bucks sets would sound wayyyy better than what I was used to
 
Something else I have thought of is that maybe these tweeters can handle power a lot easier than their woofers, so at higher volumes there is elevated treble
Tweeters are normally less able to handle power than woofers
 
You may just be sensitive to exaggerated highs. I very carefully EQ mine flattish, no peaks and sloping downwards a bit past 6kHz.
 
Music live in a studio has much more energy at the top end than almost all recordings ever transfer. Once you've experienced, you become conscious that domestic replay of commercial music is relatively lower/middle rich, than it sounds in a studio.
 
200% agree that material in no way infuses a sonic character - quite the contrary, the idea is to get closer to "perfect linearity" under different listening conditions. And indeed there are many recordings out there that are off the chart when it comes to the mixing engineers (may their souls rot in hell) amp up bass and treble to compensate for the poor equipment they continue to assume people listen on.
 
200% agree that material in no way infuses a sonic character - quite the contrary, the idea is to get closer to "perfect linearity" under different listening conditions. And indeed there are many recordings out there that are off the chart when it comes to the mixing engineers (may their souls rot in hell) amp up bass and treble to compensate for the poor equipment they continue to assume people listen on.
To be entirely fair, the ones I've talked to say they often get marching orders, from the producer or the band.
 
At what volume? In what listening environment?

Room acoustics play a major factor in how speakers sound, arguably as much of a role as the speakers themself. Room echoes and reverb, sound bouncing off the floor, walls, ceiling, and objects in the room. The "clap test" is a good way to see how sound reverberates and bounces around in your room as the volume increases.

Positioning of the speakers also plays heavily into room acoustics. Nearer a wall or corner will have more reinforced bass, and high frequency reflections may be more pronounced. Aiming the speakers directly at the listening position (on-axis) usually has more direct high frequency energy / volume, so swiveling or aiming the speakers away from LP will reduce the amount of direct high frequency volume (look at off-axis response charts for speakers at 5~10~20~30 degrees and so on). Doing this can help speakers sound less "bright", and also changes the position of the first side wall reflection point where sound is bouncing back and arriving at the LP (absorbing or diffusing this with a panel, bookshelf, fabric chair, etc. can reduce the strength of the reflected sound).

If you notice specific sounds or frequencies for sibilance, sometimes especially on cheaper or lower quality speakers there can be resonances from the driver and/or cabinet, so anything that hits that frequency gives off a subtle harsh tone.
 
Rather than cycling through different speakers, use EQ first. Assuming it's not the speakers, listening volume level, and room acoustics at play, HF "harshness" is often an inherent quality in the recording itself.
 
One of my biggest issues when listening to different speakers is that a lot sound unbearably harsh(sibilant?) to me, even if they measure flat-ish on the treble. Sometimes its hard or impossible to EQ away for some reason, even if I know where the peak is.
I noticed that the worst offenders are usually hard domes like diamond or beryllium tweeters.

1. The first point is that the cone material itself does not affect the sound (there is no "ultra fast" material). So if you equalize different tweeters in the free field to an identical frequency and phase response, they will sound identical.
There is a master's thesis from Germany that investigates exactly this. I have discussed this work in detail here.

2. However, different materials have different radiation characteristics with identical tweeter designs, as the break-up behavior is different. A silk dome tweeter breaks up very early but in a controlled manner, a beryllium dome tweeter breaks up very late and often in an uncontrolled manner, but the tweeter shows almost ideal piston behavior up to high frequencies - a silk dome does not.
You can find more details here and following posts.
As an example, here is an identically constructed tweeter with the cone materials silk, berylium and diamant. The FRs are normalized to the on-axis FR. Each diagram show the measured FR for different angles compared to an ideal piston like behaving tweeter:
1699300456223.png 1699300476049.png 1699300580148.png

3. Even small changes (small offset or tiny "waveguide") on the front plate of the tweeter lead to changes in the radiation. You can find more details here.

4. The overall radiation of a loudspeaker plays a major role (apart from direct sound) in how the sound is perceived - especially when the SPL increases.
Speakers with identical on-axis frequency response can sound completely different. Therefore, complete measurements as required by the CTA-2034-A standard are essential to identify potential problems.

For me personally, for example, in the frequency range around 2-4kHz in the sound power, early reflection and PIR, there should be no hump at all (small dip is okay, but can sound "lame", too laid back). Otherwise I perceive the speaker as harsh and aggressive.
1699301935274.png
Since SP, ER and PIR are all "averaged" curves, even the smallest changes can have a major impact on the sound.

A flat on-axis FR (and LW) is usually not enough for a good speaker sound in a normal listening room - except the speaker has perfect radiation, then yes (near field listening in heavy dampened studio is another matter).

Update:
hard or impossible to EQ away
A speaker with design flaws, like below with such radiation can never be fixed by EQ - it will never sound correct. Therefore one needs full measurements of a speaker.

1699303128237.png 1699303147513.png
 
Last edited:
Not to kick off the whole B&W thing again, but the latest ones have some odd peaks in the treble.
Not just the latest ones, to my ears. Most of the B&W loudspeakers I've heard have been ear-gougers -- the more expensive ones tended to be worse in that regard than the less more expensive ones. :(
 
1. The first point is that the cone material itself does not affect the sound (there is no "ultra fast" material). So if you equalize different tweeters in the free field to an identical frequency and phase response, they will sound identical.
There is a master's thesis from Germany that investigates exactly this. I have discussed this work in detail here.

2. However, different materials have different radiation characteristics with identical tweeter designs, as the break-up behavior is different. A silk dome tweeter breaks up very early but in a controlled manner, a beryllium dome tweeter breaks up very late and often in an uncontrolled manner, but the tweeter shows almost ideal piston behavior up to high frequencies - a silk dome does not.
You can find more details here and following posts.
As an example, here is an identically constructed tweeter with the cone materials silk, berylium and diamant. The FRs are normalized to the on-axis FR. Each diagram show the measured FR for different angles compared to an ideal piston like behaving tweeter:
View attachment 324506 View attachment 324507 View attachment 324508

3. Even small changes (small offset or tiny "waveguide") on the front plate of the tweeter lead to changes in the radiation. You can find more details here.

4. The overall radiation of a loudspeaker plays a major role (apart from direct sound) in how the sound is perceived - especially when the SPL increases.
Speakers with identical on-axis frequency response can sound completely different. Therefore, complete measurements as required by the CTA-2034-A standard are essential to identify potential problems.

For me personally, for example, in the frequency range around 2-4kHz in the sound power, early reflection and PIR, there should be no hump at all (small dip is okay, but can sound "lame", too laid back). Otherwise I perceive the speaker as harsh and aggressive.
View attachment 324515
Since SP, ER and PIR are all "averaged" curves, even the smallest changes can have a major impact on the sound.

A flat on-axis FR (and LW) is usually not enough for a good speaker sound in a normal listening room - except the speaker has perfect radiation, then yes (near field listening in heavy dampened studio is another matter).

Update:

A speaker with design flaws, like below with such radiation can never be fixed by EQ - it will never sound correct. Therefore one needs full measurements of a speaker.

View attachment 324518 View attachment 324519
Doesn't a differing breakup behavior also indicate different levels of THD, even if the FR is equal? In which case silk / paper / aluminum differences might be audible if the first breakup mode was low enough?
 
Doesn't a differing breakup behavior also indicate different levels of THD, even if the FR is equal? In which case silk / paper / aluminum differences might be audible if the first breakup mode was low enough?

With a good dome and surround design, the drive motor of the tweeter should be decisive. In post#18 I used three Bliesma tweeters with identical drive motor and front plate but different dome as an example - you can find the reviews here.

The measurement of the harmonic distortion (about 90dB@1m) is almost identical in the intended operating range above 2kHz and at least in this example practically without influence:
1699318770582.png 1699318793324.png 1699318806512.png
Source

In addition, harmonic distortion is extremely difficult to hear due to masking effects.
 
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