2. speakers
  3. 189459-13640

ribbons vs domes and sibilance

I came upon a thread from the DiyAudio site titled "Can you have sparkling treble but without sibilance?" from 2011. The discussion is very technical and as such, completely over my head but one participant asserted that ribbons are far less prone to sibilance than domes. 

Here's an excerpt for the technically minded: :

... the middle of the dome basically flops about doing it's own thing at high frequencies as it's only very loosely coupled to the edge because of it's own less than infinite stiffness. Thus any distortion or resonances that occur due to the middle of the dome bending and moving in non-piston ways are not reflected back to the amplifier via back EMF... when the ribbon is only 8mm wide compared to a 25mm dome, there is far less narrowing of dispersion with increasing frequency than a dome. The directivity control is achieved with a wave-guide instead. This is why a wave-guide loaded ribbon can achieve an almost constant 90 degree horizontal dispersion from 2Khz right up to 20Khz - the ribbon element itself is far less directional horizontally at high frequencies than a dome, with the wave-guide then adding in a constant directivity control.

I'm wondering whether any forum members have compared speakers with domes and ribbons in regard to sibilance and arrived at any conclusions. 

stuartk
mike_in_nc
1,122 posts
 

A lot, IMO, depends on the implementation. I have used speakers with ribbon tweeters and currently use speakers with electrostatic tweeters and feel that ribbons and electrostats typically have very clean treble, which makes them less prone to exaggerate sibilance. However, I would imagine a well engineered dome tweeter in a well engineered speaker also could be good.

To my mind, the frequent causes of sibilance are frequency anomalies from 8 kHz to 10 kHz. They may be caused by microphones that have peaky response or speakers that likewise have peaky response. (Many audiophile speakers have peaks around 10 kHz.) Also, any part of the reproduction chain that adds distortion to high frequencies will likewise cause sound that is similar or identical to sibilance. Finally, poor room acoustics if untreated will compound the problem.

 

stuartk OP
2,371 posts
 

@mike_in_nc 

Thanks for your comments.

erik_squires
15,737 posts
 

Like with any driver, implementation matters.  Modern dome tweeters are far far better than described there, and some ribbons are notoriously splashy.  That is, have a lot of distortion which makes them sound extra airy.  Also, not sure how many ribbons out there have wave-guides to begin with, most of the ribbons I can think of do not.  Among the most expensive, RAAL, for instance, I can't remember seeing one wiht a waveguide.

If that's what you are looking for I encourage you to look at the top-end Mundorf capacitors as IMHO they stand out because of this kind of coloration.

Also, a GOOD AMT beats them both for high frequency extension, low distortion, and power handling.  The Beyma horn loaded AMT is particularly interesting for wide dispersion.

More to discover