just taking an idea from sonus faber lilium, it has a tuned mass damper insde the cabinet to reduce cabinet virbation
now compare to taiwan101 tower it put a mass damper on the top of the building instead using the total length of the cabinet
Which one it the proper implementation ? to me it seems the tower is the proper implemntation becasue it also take account of the horizontal and vertical virbation.
Now we put this mass damper design into a vented box, shall we creat a seperate enclousre on top of the box so we can eliminate the accoustic sound the mass damper created ?
now compare to taiwan101 tower it put a mass damper on the top of the building instead using the total length of the cabinet
Which one it the proper implementation ? to me it seems the tower is the proper implemntation becasue it also take account of the horizontal and vertical virbation.
Now we put this mass damper design into a vented box, shall we creat a seperate enclousre on top of the box so we can eliminate the accoustic sound the mass damper created ?
Uh, sure, which single frequency would be best? That's all that a "tuned" mass dampener can do, affect a single frequency. I don't think it will help all that much in a loudspeaker no matter what the flashy Sonus Faber video clip claims.
The comparison with a skyscraper tower is non-sensical because they are completely different from a mechanical perspective. The tower has a fundamental resonance that is excited by wind energy and other vibrations. This is effectively reduced using the tuned damper, when tuned to the building's fundamental resonance frequency (at which is would sway back and forth, not a vertical vibration/motion).
Fundamental resonances of large engineered structures, when poorly damped, can lead to catastrophic failure. A great example is the Tacoma Narrows suspension bridge. This is a great video on that and related engineering topics:
Also, this is a good video on tuned mass dampeners in skyscrapers and how they are used to reduce motion:
The comparison with a skyscraper tower is non-sensical because they are completely different from a mechanical perspective. The tower has a fundamental resonance that is excited by wind energy and other vibrations. This is effectively reduced using the tuned damper, when tuned to the building's fundamental resonance frequency (at which is would sway back and forth, not a vertical vibration/motion).
Fundamental resonances of large engineered structures, when poorly damped, can lead to catastrophic failure. A great example is the Tacoma Narrows suspension bridge. This is a great video on that and related engineering topics:
Also, this is a good video on tuned mass dampeners in skyscrapers and how they are used to reduce motion:
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Some info about SF damper system here
https://audio-head.com/sonus-faber-announces-a-new-flagship-aida/
https://i0.wp.com/audio-head.com/wp-content/uploads/2017/11/DSC210922.jpg?resize=1024,683&ssl=1
The real problem is first standing wave in longest (vertical) direction of the tower box. Pressure variations induce cabinet resonances/vibrations with higher frequency.
SF upper end 3.5-way speakers have a bottom-mounted subwoofer and front-facing woofers, which all have separate air volume (internal boxes).
https://audio-head.com/sonus-faber-announces-a-new-flagship-aida/
https://i0.wp.com/audio-head.com/wp-content/uploads/2017/11/DSC210922.jpg?resize=1024,683&ssl=1
The real problem is first standing wave in longest (vertical) direction of the tower box. Pressure variations induce cabinet resonances/vibrations with higher frequency.
SF upper end 3.5-way speakers have a bottom-mounted subwoofer and front-facing woofers, which all have separate air volume (internal boxes).
Mass Damper seems more of a marketing term.
Looks more like a steel rod used for basic bracing
or add pre tension.
simple test.
Find a old speaker box that has audible rattle.
Tighten a bar clamp from top to bottom.
Or side to side, the rattle stops.
Same idea, bar clamp is just hidden inside the cabinet.
Steel rod with washers and bolts to add tension
or maybe not.
cabinet can " balloon" under pressure.
pre tension would likely be effective outward
Looks more like a steel rod used for basic bracing
or add pre tension.
simple test.
Find a old speaker box that has audible rattle.
Tighten a bar clamp from top to bottom.
Or side to side, the rattle stops.
Same idea, bar clamp is just hidden inside the cabinet.
Steel rod with washers and bolts to add tension
or maybe not.
cabinet can " balloon" under pressure.
pre tension would likely be effective outward
This isn't likely to be a solid connection. From what I can see it is more likely to damp either resonance conveyed through the braces, or movement of the whole cabinet.
I was just searching around about this subject and some related stuff, and I just had to make an account to update this thread with some of my findings:
Sonus Faber Lilium is not the only speaker which uses a tuned mass damper; Focal speakers also do. They have a page about it here: https://www.focal.com/en/focal-teach/tmd-tuned-mass-damper
I think the potential for using TMDs in speakers is much more similar to how they are used in cars than how they are used in buildings. Wikipedia says that "Almost all modern cars will have one mass damper, and some may have ten or more." Some of the vibrations that page describes even sound like they could be at audio rate already.
Ultimately I think the effect will be similar to adding a filter via dsp or analog circuity.
Sonus Faber Lilium is not the only speaker which uses a tuned mass damper; Focal speakers also do. They have a page about it here: https://www.focal.com/en/focal-teach/tmd-tuned-mass-damper
I think the potential for using TMDs in speakers is much more similar to how they are used in cars than how they are used in buildings. Wikipedia says that "Almost all modern cars will have one mass damper, and some may have ten or more." Some of the vibrations that page describes even sound like they could be at audio rate already.
Ultimately I think the effect will be similar to adding a filter via dsp or analog circuity.
The best part of the Sonus Faber was the use of bubble wrap to help kill the backwave, imo.
Usually bracing and mass take care of anything in speaker cabinets.
I didn’t think the Tacoma Narrows bridge failed from harmonics outright, it was from the increased sail area provided by the solid panels used for railings. The engineers advised them not to do that, and to use typical railings for that reason, but politics won out.
Usually bracing and mass take care of anything in speaker cabinets.
I didn’t think the Tacoma Narrows bridge failed from harmonics outright, it was from the increased sail area provided by the solid panels used for railings. The engineers advised them not to do that, and to use typical railings for that reason, but politics won out.
This may actually have a little more basis in science. The data that SF shows seems to indicate it is helping to distribute one main surround resonance into 2 or more modes, each of which is lower in amplitude. So, kudos for that.
Just keep in mind that all companies need to roll out some new marketing mumbo jumbo and eye-grabbing bling periodically to try and motivate potential buyers into thinking that their product has some feature(s) that the competitor does not, and is therefore superior and a purchase should be made. This is essentially the same across all industries, and is just marketing 101. Keep a skeptical mind about such claims...