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Is there any science to back up these little feet

Compliant suspension is proven technology, it's why your teeth don't fall out when you drive your car over the countless potholes in Manchester.
 
Yes they do. Anything on rubber feet will vibrate less. See also BluTak, a sandbag, a bicycle inner tube, springs, marshmallows, carefully arranged fish fingers or anything else.
Does this affect the sound of the article resting on them? This is what you don't know.
 
Rega used a similar substance on their planet 2000 player i owned, the reason being the player has no error correction circuitry so needed special rubber feet to prevent vibration so I suppose there must be something to these feet but as you say, how can this effect the sound.

I have read differing views on this subject, some go for absorbing vibration as with these while others go for removing energy through a cone , to drain energy away from the item rather than have it be stored underneath it.
 
Interesting. Vibrations can be absorbed, certainly. Does it make an audible difference, tricky.
Other than my turntable where vibrations matter, I'm skeptical it makes much different to solid state devices.
Although in no way can I see it being of any harm either.
So like ensuring you have good cables, there's an argument here to say all these little measures do help ensure there is an absence of issues that inadvertent circumstance (faulty component for example) could otherwise be sensitive to.
So, it's a difficult one, but it's interesting all the same. If it's not costing a lot I suppose no harm to take these measures as precautionary. I've not done this myself, as-yet.
I wouldn't rush out to spend a load of £££ on these sort of measures though, myself.
 
Rega used a similar substance on their planet 2000 player i owned, the reason being the player has no error correction circuitry so needed special rubber feet to prevent vibration so I suppose there must be something to these feet but as you say, how can this effect the sound.
Slight correction, the Rega players do have EC but rigidly fixed the disc carrier (and therefore the sensitive laser focus servo) to the cast casework, then suspended the whole thing - using the mass of the whole player - on squishy feet to get a lower resonance (give the focus servo less to do) than laser mechs usually do mounted directly on the tiny grommets most use. Simple, cost effective, typically Rega alternative approach (- but might skip if you tap the player)
 
Relatively recently moved to sonic design pads (£20) under my floor standing speakers. Still can't find any coherent science to support spiking speakers to suspended wooden floors unless you want to get the floor singing along.
 
These aren't Nordost Pulsar Points or other foo - they are made to go under washing machines - hence the non-audiophile price tag - you wouldn't be asking if they "worked" if you were sticking them under your washing machine, you'd just do it.
 
http://www.mains-cables-r-us.co.uk/hi-fi-equipment-supports/278-deflex-polipods-isolation-feet.html

Is anyone aware of any science to back up that these little rubber feet actually absorb energy from vibration, I suppose it's claimed it turns it into heat but can anyone actually provide written evidence of this or is it more a case of changing the sound rather than anything scientific.
Their blurb is not quite right.

Good vibration isolation simply requires a soft spring to give a resonance of the device on the rubber feet well below the lowest frequency you wish to isolate. The presence of significant damping will degrade the performance. If the resonant frequency of the device on it's feet lies within the frequency range you want to isolate the device from then it will obviously make things significantly worse around this frequency. High vibration isolation does not absorb energy.

Damping is beneficial at resonance where the forces due to inertia and stiffness cancel leaving only the forces due to damping to oppose the motion. So a high damping coefficient is good in this respect but, unfortunately, it would need to be in the form of a sheet stuck to the surface of the device in order to pickup and oppose the vibrating motion of the device. Damping does dissipate energy.

So the stiffness of the feet in combination with the mass of the device will have almost certainly too high a resonant frequency to isolate the lowest frequencies, it will make the vibrations worse at frequencies around the resonance but would have isolated the higher frequencies to a good degree if it didn't have high damping. Which it claims to have. It seems to be humorously poor for the task.
 
Their blurb is not quite right.

Good vibration isolation simply requires a soft spring to give a resonance of the device on the rubber feet well below the lowest frequency you wish to isolate. The presence of significant damping will degrade the performance. If the resonant frequency of the device on it's feet lies within the frequency range you want to isolate the device from then it will obviously make things significantly worse around this frequency. High vibration isolation does not absorb energy.

Damping is beneficial at resonance where the forces due to inertia and stiffness cancel leaving only the forces due to damping to oppose the motion. So a high damping coefficient is good in this respect but, unfortunately, it would need to be in the form of a sheet stuck to the surface of the device in order to pickup and oppose the vibrating motion of the device. Damping does dissipate energy.

So the stiffness of the feet in combination with the mass of the device will have almost certainly too high a resonant frequency to isolate the lowest frequencies, it will make the vibrations worse at frequencies around the resonance but would have isolated the higher frequencies to a good degree if it didn't have high damping. Which it claims to have. It seems to be humorously poor for the task.
So in your opinion what are customers "hearing" with these feet under the cd player for example, they claim the sound improves but few say how.

Feet etc.. must have some effect on sound because if I place my cd player on my carpet & compare it o when it sits on my shelf, the sound changes quite dramatically. The squidgy feet probably have some effect but have doubts about the write up on the packaging, I feel more the sound is just changing due to being housed on a different surface.
 
If you have vibrations inherent inside the component or speaker, rubbery feet do little to help them escape.
 
If the servo circuit thSt controls laser focus and tracking is poorly isolated from the rest of the power supply in the cd player it could modulate the power going to the rest of the player. There's a whole slew of viable noise mechanisms in cd players.
 
I tried squashy feet under my power amps it sounded terrible so I put the hard ones back on, I don't know it it was the amps (135 clones) that didn't like the feet, or the frame with every thing else on didn't like the way it was being affected by the soft feet on the amps.
So one simple change could affect other components.

Pete
 
If the servo circuit thSt controls laser focus and tracking is poorly isolated from the rest of the power supply in the cd player it could modulate the power going to the rest of the player. There's a whole slew of viable noise mechanisms in cd players.

It would have to be spectacularly poorly designed for this have an effect.
 
http://www.mains-cables-r-us.co.uk/hi-fi-equipment-supports/278-deflex-polipods-isolation-feet.html

Is anyone aware of any science to back up that these little rubber feet actually absorb energy from vibration, I suppose it's claimed it turns it into heat but can anyone actually provide written evidence of this or is it more a case of changing the sound rather than anything scientific.

You have to divide this question into two (at least)
1) do the little rubber feet absorb energy from vibration
2) does vibration make any difference to the electrical output of solid state components

This is still very vague and misses out many points eg
what vibration? (airborne or from the floor) at one end
and
difference for the better? at the other end

This was pretty much some to death in an earlier thread. But if you don't at least make this distinction then you are just not going to get off the ground.
 


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