The Battle between Stiffness And Damping Of The Speaker Enclosures!


This is a good article I found on 6moons! 
 
Not connected with this company in any way
  

  
https://www.6moons.com/audioreview_articles/aequo3/
highend666
As is usually the case, I simply cant get through most 6 moons reviews. I will revisit later after a bit as I am very interested in this subject. Thanks for posting. 
And what will we do when we get this super stiff highly damped speaker? Put it on springs.
As the chart shows plywood has a stiffness of 8 and diamond has the highest at 1050. 

The perfect speaker would therefore be made of diamond. Why hasn't anybody done it? Or have they? 
Well you would need diamonds bigger than the Hope Diamond  but you could ask Howard Rather from Uncut Gems to get some ...Oh wait he's dead.
Some say these Volya Bouquet Loudspeakers could be one of the very best on the market right now.. 
 
I've never heard these speakers yet but a friend of mine up north replaced his big Soundlabs with these and never looked back!  These are way out of my price range though!

 

 https://www.hifipig.com/volya-bouquet-loudspeakers/
Unique.Now if they could only design some monitors that look like Venus flytraps....
"These Volya Audio Bouquet speakers present a 3D illusion that is very hard to distinguish from the REAL THING"  
 

 
 https://www.6moons.com/audioreviews2/volya/1.html
This is interesting but is very confusing.  It blurs the discussion between driver and cabinet material which I am not sure if that is intentional.   Additionally, it seems to take an intentionally simplistic view of some of these materials without considering real world applications.  

That being said, I applaud the use of advanced materials and delivering them at what appears to be prices that aren't insane.  It does highlight and illustrate why moving beyond wood and MDF makes sense.  I would love to hear these.  

Thanks for sharing
Some say these Volya Bouquet Loudspeakers could be one of the very best on the market right now..
Seems unlikely. With rated sensitivity at 86dB, and impedance of 4 ohms, when you work out the math the efficiency is 83dB. That is a speaker that needs a lot of power to play anything unless in a very small room, and will suffer from thermal compression. To give you can idea of what I'm talking about, in my room I can reach 105dB without stressing the amplifier- at that level the system still sounds relaxed and smooth. My amps only make 60 watts but my speakers are 98dB 1 watt/1meter.

If I had those speakers in the same room to reach the same sound pressure level I would need an amplifier with about 2000 watts. Plain and simply, there really aren't any amps that make that kind of power and sound like real music. IMO these speakers are criminally inefficient unless you are unconcerned about playing most music at anything approaching realistic.
Very interesting....

They are truly horrible look and now proven flawed in design....


atmasphere
  
In the 6moons review on page 4, they said they used a 300B amp with only 8 watts and it worked just fine and their room is not small.
I think it depends on the listening level highend666. 

If the gentleman at 6moons prefers listening to a peak level of 85DB, then of course the 8 watt should be sufficient. 

105DB at the listening position with those speakers is probably a pipe dream. 
In the 6moons review on page 4, they said they used a 300B amp with only 8 watts and it worked just fine and their room is not small.
If the specs are correct, then this was entirely inappropriate use of an SET, since it would have been making a lot of distortion to make significant (above conversational level) output. Because much of this distortion would have been higher ordered harmonics on the transients, I bet they were saying it sounded really dynamic. But because the ear uses the higher ordered harmonics to sense how loud a sound is, what was really going on was the distortion masquerading as dynamics.
I saw this posts and couldn’t resist to sign on and clear things up. I know it’s a complex topic but let’s try:

“And what will we do when we get this super stiff highly damped speaker? Put it on springs.”

Good question. 👍🏻The answer:If the cabinet is stiff enough to not vibrate within its walls and well damped enough to not resonate, it depends in the moving mass and positioning of the drivers if it lives and how much “spring” it needs. Hence some speaker to well with some rubber/damping in the feet while others need something solid.  Less spring (softness) means better imaging precision and efficiency. Just as important is the mass of the cabinet: lighter cabinets such as the Stilla (26kg) but with very powerful and deep lf needs all kinds of measures to keep it from starting a dance on the floor, such as can be read in this paper: https://static1.squarespace.com/static/5690c974a976af0bfc4aeaaa/t/5b14f34370a6ad083bf0a3cf/1528099675199/Stilla_development_story.pdf


“Diamond is stiffer, so better”

Diamond is very poor in damping. It will more easily ring/resonate relative to various other components. It also depends on the cvd process, dimensions, and the type of coating (enhancing damping). Not to understate the extreme costs… To understand more about new and better materials, please visit our sister company for b2b projects : www.diluvite.com “Cabinet materials and driver membranes are not the same” 

Indeed, they are certainly not. Membranes have to move and therefore need to be sufficiently lightweight for better efficiency. This also lowers structural basket/enclosure demands.  And they often handle not the full audio frequency spectrum. LF drivers need stiffness especially, to prohibit flexing under high force, whilst midrange membranes need a high level of combined stiffness and damping. Depending on frequency band/ filter type they need more stiffness (upper bass) or more damping (to lower thd in the upper pass band). For HF drivers it is more complex as in small pistonic tweeters, very high stiffness might help to push resonance far enough up to best benefit from this property. But without damping, still some unnatural crisp or sound signature might be observed. 

“Oversimplifying material physics in view of the real world practise”

This is THE abundantly occurring problem. In practice we need to consider the specifics and goals of the application including static and dynamical design. For  both cabinets and pistonic membranes we need to look not only at stiffness, damping and weight but also on damping loss vs frequency and dimensional inflicted resonance at the eigenfrequency and avoid circular and rectangular solids as well as avoiding flat walls and non-variable wall thickness. Combining (sandwich) of materials with different properties is also helpful and last but not least: tension loading (such as with bolts) have huge benefits for damping. In my attempt to explain things more easy and thoroughly, I wrote this paper to present the first Diluvite-made speaker cabinet: https://static1.squarespace.com/static/5690c974a976af0bfc4aeaaa/t/5e9d108139f0f40fc886249b/1587351700710/ADAMANTIS+Creation+of+a+Nano+Infused+Zero+Resonance+Loudspeaker.pdf

Hope this helps or some find it interesting.