What is vibration isolation for?

Tom.

We are not fighting mother nature, we are fighting one man made invention with another. If we could hear human powered music exclusively and not have to deal with electronics, the vibrations would be fun.

First they put springs under a turntable and claim success. Next they'll be putting springs under automobile suspensions, claiming it makes the ride smoother.

What next?

Pbb, I am coming into this discussion a bit late, but do I understand you are saying that any device placed under amps or other electronics have no audible affect?

If so, you have either never conducted an experiment or your system is in dire need of improvement. There is no question as to the benefit of isolation.

Certainly some equipment benefits more than others, and there are a few rare pieces that are best left alone. But to say that ALL equipment is NEVER improved with ANY isolation device is just wrong.

Neither is cost the controlling factor in this truth. There are devices that cost $6.00 which offer tremendous benefit, and some which cost $200.00 that are great benefit.

Your suggestion that money somehow attaches the user to the device has completely failed in my case. My preamp retails for more than $10,000.00 and is isolated by $10.00 devices.

My $30,000.00 speakers work best with $55.00 isolation devices, yet my stock Sony SACD player has Symposium Roller blocks which cost several hundred dollars.

Each device chosen for it performance benefit, dismissing cost all together as a factor.

Neubilder, things under the chassis are isolation if they help reduce the effect of outside forces effecting performance.

A rubber foot under a preamp can alter the resonant frequency of both the preamp and the shelf it is resting on. The shelf and preamp may both be vibrated by the same bass pounding (your description), but as long as the foot reduces or alters the frequency of the vibration, there will (likely) be a change in sound.

I will not argue that all changes are good. Some rooms, shelves, equipment chassis (etc.) benefit from a certain isolation device or foot, and not another.

There are other ways to effect or isolate the equipment, such as shelf materials that block magnetic energy or RF. There are damping sheets that may be applied directly to the chassis, inside or out that reduce the ring of the materials it is attached to.

Some prefer the sound of equipment with a weight applied to the chassis. There are many ways to pull that off, some expensive and some for free. Again, this changes the resonance of the chassis and or the material it is sitting on.

My point is that there is a change, and all of the ways I have listed may make a sonic difference. Some will be perceived as good, some trade off and some as bad. The whole point of discussing tweaks like these are so others may experiment and find what works for them. I never dismiss any idea until I have put it to the test.

Vibrations come from the speakers and particularly the bass, as was already stated. That energy shakes the audio chassis, the floor, the equipment stand and everything in the room to one degree or another.

A reviewer friend at Absolute Sound is so picky about this that he refuses to have his turntable and phono stage in the room with the speakers. He begins the track and walks back into the listening room and settles down for that side of the LP.

This stuff is very difficult to explain and probably even more difficult to measure. The easy way to see if there is a gain to be had is put aftermarket feet under equipment X and listen. The stock feet need not be removed to make the test unless they are so big that the aftermarket feet fail to touch the resting surface.

This is really very simple to do, costs almost nothing and will allow you to hear what the effect is. As I said before, you may have performance gain or loss depending on the many variables involved.

If you have no feet to try, I could ship you my spare Mod Squad Soft Shoes. They are my all time favorite low bucks device. They are successful on more types of equipment than any other foot I have tested.

I use more Squad feet in my system than other device, but still employ six other brands in one spot or another to get the desired results.

While your post is not aimed at me specifically, I am going to take it on. Your comments are copied and pasted below.

"I will trot out the usual question-to-end-it-all (and will probably get the usual stock answer): why would the manufacturers of ultra-high-end transistor amps sold for kilo bucks not build the best isolated chassis possible if this is such a concern?

My response:

First, your question begs the same answer as the previous posts that question why high end manufacturers do not include audiophile power cords with their products. I will answer BOTH of these issues, because they can both be answered by the same response.

First, there ARE manufacturers that in order to keep the performance to price ratio in line for their place in the market, choose NOT to include these additional cost items.

However, there ARE manufacturers that charge enough for their superior performing products THAT DO include these.

Examples are manufacturers such as Walker Audio, who include two very high end aftermarket power cords with his best turntable. One goes from the wall outlet to the motor controller and one from the motor controller to the turntable motor. This is an example of two power cords improving a rotating motor, turning a belt, driving a 70 pound platter. Not only is it audible, it is necessary to the performance of the product.

Second, there are manufacturers that DO use special damping, copper cladding and / or high grade machined chassis's to improve isolation.

A quick look on the internet will allow you to view examples from Pioneer who use honeycomb embossed low resonance chassis for their high end products, many of which are clad in copper.

Machined aluminum billet construction is employed by Rowland for their transistor amps. By CTC in their Blow Torch transistor preamp, and Rockport in their isolated transistor motor drive for their turntable. These are a fraction of the companies that believe in this technology and use it in their production.

Third, there ARE companies that manufacture their products with SPECIAL ISOLATION FEET as part of normal product production. Prime examples are the Number Cruncher D to A manufactured by Entec which is equipped with the Vibrapod aftermarket isolation foot as standard issue.

McCormack Audio supplied Soft Shoes (Trade Mark) as an OEM part. They were sold by the thousands and installed as the standard issue isolation foot on many audio products.

This is not alchemy or fiction, many of these product's were inspired from Military and or NASA space research programs.

Audio products benefit from trickle down technology from better funded sources that are working to solve isolation and vibration problems. These are real problems and the solutions wind up helping those of us that care about making things the best they can be.

Audiogon is a site that is frequented by audiophiles who concern themselves with the passion for music and the tools necessary to make it the best it can possibly be.

There are visitors who are content with bedside radio, and those who will pay any amount to retrieve the last bit of realism from their music systems.

No crazier than musicians who seek vintage Genelex KT88 tubes in order to achieve vintage sound from their electric guitars.

The passion for "getting it right" is not new, even if in conflict with your idea as to what constitutes good value.

You may dismiss these advancements, call them frivolous and doubt those who seek to make the experience better, but until you become open minded enough to listen to these products work their magic in a direct listening session, you will never understand.

Audiofile9, it appears you and I posted answers to the Pbb posting at the same time.

Our responses from similar positions, hoping to explain what should be obvious.

This continuing discussion reminds me of the story of the big game hunter stalking the grizzly bear.

The hunter drawing near the beast, levels his weapon to fire but is suddenly overpowered and sexually abused.

Returning to the same spot the next day, the bear again gets the jump on the hunter and is sexually abused again.

The third time the hunter returns he is startled when the grizzly suddenly rises up from the bushes, getting the jump on him once more.

Just before the bear begins to take advantage again he asks, "You don't really come here to hunt do you?"