[gary]

This is my first official review, and it's a pretty good one so I'd thought I'd post a link here.

http://www.positive-feedback.com/Issue13/pandafeet.htm

Gary

[byteme]

This is my first official review, and it's a pretty good one so I'd thought I'd post a link here.

http://www.positive-feedback.com/Issue13/pandafeet.htm

Gary

Pretty good?  I'd say damn good!  Well done Gary, good for you!

[Hantra]

Gary:

Weren't you thinking of building little plexiglass speaker cable elevators?

Or am I losing my mind?  <---  likely. .  

B

[gary]

Pretty good?  I'd say damn good!  Well done Gary, good for you!

Thanks, byteme. An overly positive review like that kind of scares me though, I'm afraid of unrealistic expectations from customers who want the world from a $20 tweak. We'll see how it goes I guess.

Hantra-

I did have an idea for acrylic cable elevators, and there's actually been a bit of interest in them lately (even though I pulled the page from my site months ago). I'm probably going to contact the supplier I had my original quote from, and so long as he will do it for the same price I'll have a batch made. If he won't or if he's out of business, then I doubt it'll happen because everyone else I talked to was around 3 to 10 times the price and that would make them unreasonably expensive. I'll keep you posted either way.

Gary

[Hantra]

Thanks man!  

I sure could use some.  The ones I have now are the only remnants I have from my gayer audio days.  LOL!

[martyj]

This is my first official review, and it's a pretty good one so I'd thought I'd post a link here.

http://www.positive-feedback.com/Issue13/pandafeet.htm

Gary

Gary,  

Congratulations..great review.  I know my system has never sounded better since I picked up my panda feet from you.  Great isolation, excellent sound.  Great customer service and helpful, friendly guy.

martyj

[gary]

Thanks marty

Mind if I quote you on that?

Gary

[martyj]

Thanks marty

Mind if I quote you on that?

Gary

Please quote me all you want.    

Marty

[martyj]

Thanks marty

Mind if I quote you on that?

Gary

Please quote me all you want.    

Marty

[mcgsxr]

Congrats Gary, nice to see that your combination of quality products, and friendly service is being recognized a little more broadly now.

Good for you,

Mark

[DSK]

Hi everyone,
Let me make it clear at the outset that this post is not intended to have a go at John Zurek (the reviewer), Gary, Panda Feet or anyone else ...I'm even considering giving them a try to be honest ...

However, there are some things in the review that puzzle me. I'm certainly no expert on isolation and damping. I've done lots of reading etc in order to help me get on the right path as far as the concepts and strategies involved so that I am better placed to choose products to try, but have done limited testing so far.

John says that he used the Panda Feet with the Vibrapods still in place. Unless I am misreading what he is trying to say, it seems that he would be totally destroying the intended load ratings of both products by using both of them under the turntable at once. It seems most unlikely that improvement would result from the resultant chaos, at least not all of the improvement possible by using them correctly.

He also talks of thumping his turntable as a test of the Panda Feet isolation. Although I guess the compliance of the Panda Feet would help against airborne vibrations, surely it is a more apt test to thump the rack instead. After all, primarily we are trying to isolate the components from the floorborne noise coming up through the rack (that is why the feet sit between the component and the shelf). The squishy feet between the component and the shelf act to minimise the vibration transfer between the two. This means that resonance in the component caused by airborne vibrations or self-generated resonance (motors, transports etc) is now trapped within the component and should be treated with damping products on and/or within the component itself (eg. rope caulk, dynamat etc).

Also, he goes on to say that he will try an additional set of Panda Feet between the rack and the shelf. This would give him two identical but separate isolation layers between the rack and the component. Everything I have read from people with qualifications/experience in this area indicates that this is NOT the way to do isolation.

I have no problem accepting that John heard what he heard. However, it seems to me that he has little idea of how isolation actually works and any improvements achieved will be due to accident rather than science. Even an accidental improvement is good, but without understanding why there was improvement it is much more difficult to optimise the improvements.

Again, not trying to discredit John, but perhaps it is worth noting that we should not blindly accept a reviewer's writings as fact or even knowledgeable, IMHO.

As I said, I'm also not suggesting that PandaFeet don't work. I actually do agree with the principle of load ratings on compliant products for isolation and may try them. Indeed this concept is used in industry with heavy machinery. If they work well, they are certainly a nice change from the way overpriced "audiophile" products like the Symposium RollerBalls that I currently use (they work very well but are ridiculously expensive).

IMHO it would be better to use Panda Feet between the rack (preferably light and rigid in order to raise the resonant frequency and enable the isolation product to work better) and a well damped (perhaps constrained layer) shelf, with rigid coupling between the component and the shelf. This would minimise the floorborne vibrations reaching the component and would enable the component's self generated vibrations, and those caused by airborne vibrations, to drain (via the rigid coupling) to the non-resonant shelf and be damped. Of course, until I try the Panda Feet this is in theory and only actual testing and listening will determine whether it translates into more effective resonance control and more lifelike music. But, at least it is more solidly based on the principles of isolation and damping than adhoc guesswork.

I appreciate reviewers' efforts to lead confused audiophiles down the path to sonic nirvana. However, when they are reviewing products based on principles that they don't understand, I feel that it is their duty (having taken on the responsibility of the role of a reviewer) to clearly state this up front and to report only on what they hear. Making wrong assumptions or recommendations based on wrong assumptions may lead readers down the wrong path, leading to less than optimal results and wasted time and dollars.

I'm interested to hear experiences from people who have tried the Panda Feet in various setups, how they used them (details of their total setup from floor to component) and what the subjective results were. Comparisons with previous setup/products would be interesting too. I honestly feel that there is potentially more to be gained from this than from the review mentioned above. Although it could be argued that he is biased, I'm sure Gary has done more testing of the Panda Feet than anyone else and would like to hear his views and recommendations.


Just my $0.02 worth      

[Red Dragon Audio]

Hi everyone,
Let me make it clear at the outset that this post is not intended to have a go at John Zurek (the reviewer), Gary, Panda Feet or anyone else ...I'm even considering giving them a try to be honest ...

and strategies involved so that I am better placed to choose products to try, but have do ...

Hi DSK,

I ordered a few sets of PandaFeet because Gary, the designer, was extremely helpful in answering all (and I mean all) of my questions regarding his product.  His responses weren't just some generic off the shelf answers but were in-depth and specific to my exact situation.  Of all the folks I have dealt with in online businesses he ranks in my top5.

Beyond his excellent answers he offered the standard 30 return policy and even said he would cover the return shipping if I didn't like them (Yeah I know $3.85 isn't major but it's the fact I wouldn't lose a dime that counts.  I like that kind of gesture).

Anyway...I was going to say that once I get the PandaFeet and have tested them in my setup, I would be happy to send you an email about my experience with them.  I will also post my personal evaluation here as well.

 

[gary]

Hi DSK,

That was a great post, and after looking it over quickly I'd say I definitely agree with a lot of what you're saying. Unfortunately I've been travelling all weekend, and I leave tomorrow for a week in Europe. I'll try to come back with an indepth response soon, maybe I'll work on it on the plane.

Gary

[DSK]

Hi HEAVYSTARCH and Gary,
Thankyou for your replies and I look forward to hearing more thoughts from you both.

Hopefully no readers took my comments to mean that the review was worthless. Although the reviewer may not have understood the theory, the fact remains that he heard an improvement. Some of us care about the theory and some don't, but we all want improvement!  

After my post, I read the FAQ on Panda's site and saw that Gary recommends to "always use them directly under the component". This does follow the golden rule of applying isolation as close to the component as possible. I have no problem with this and indeed that is how I currently use my RollerBalls and Aurios.

The general idea is to try to raise the resonant frequency as the vibrations travel from the floor up toward the component. Large, heavy racks have a lot of mass and a low resonant frequency. Once excited, it takes a long time for this energy to dissipate. The more massive the rack, the lower the resonant frequency, the more momentum and the more difficult it is to treat. Kind of like trying to stop a semi versus stopping a car, using car brakes on both. If you live next to a train line, a passing train will cause your house and everything in it to vibrate. If you touch your finger to a resonating wine glass it will damp the resonance and stop the ringing. However, if you touch your finger to the wall, the damping properties of your body are insufficient to stop the more massive wall from vibrating.

This is why more people are adopting the "light and rigid" approach. The smaller and lighter an object is, the higher its natural resonant frequency will be. The more rigid it is, the more uniform its resonant behaviour. Isolation and damping devices are like filters that work only down to a certain frequency. This frequency is determined by the material used, its size, hardness, shape, load etc. Resonant frequencies below the effective filtering frequency of the device will get through to the component. So, the higher we can raise the resonant frequency as the resonance travels toward the component, the closer this frequency will come to the lower limits of the device and the less resonance will get by it and reach the component. Like the crossover frequency of a speaker crossover, the effective frequency limit of an isolation/damping device is not an on/off brickwall filter, there will be a tail off or overlap.

Thinner, smaller, more light weight objects will resonate or accelerate more quickly (like a small car versus a truck), but they will also decelerate (brake) more quickly due to their lower mass. They therefore require less damping (braking) than a more massive object, or will decelerate more rapidly given the same amount of damping (braking). Energy can only be dissipated in two ways ...as "work" (eg. the forced movement of roller balls) or as "heat" (eg. foams). Note too, that while we need open cell foams to effectively treat airborne vibrations, closed cell foams are more effective for structure borne vibrations.

If we adopt multiple layers of isolation within the structure, they will each be effective at different frequencies and the result can be very unpredictable. Without the benefit of expert understanding and complex calculations it seems preferable to keep things very simple and focussed. Thus my suggestion of a light but rigid rack (to raise resonant frequency), a light but rigid and well damped floating shelf (eg. constrained layer) that supports little resonance and at a higher frequency still, and an effective isolation device that ideally can isolate down to frequencies below those supported by the structure beneath (Pandas, rollerballs, inner tubes etc).

Airborne vibrations will cause the damped floating shelf to resonate somewhat, so it makes sense to place the isolation device between the component and the floating shelf (as recommended by Gary) to remove this aspect. The reason I suggested placing the isolation device between the rack and floating shelf was based on my previous experience with Vibrapods. Like the Pandas, these too were load rated for optimal performance. However, I had very mixed results with them directly under the component and generally preferred them between the rack and the floating shelf. Ultimately I found the rollerballs/Aurios to be more effective but about 20 times more expensive.

So, I would be very interested to hear the results from people who try the Pandas in both places in such a setup as I have described. I may even get around to doing this myself when I have some time.

Again I stress that I am no expert in these matters and you should take my opinions and suggestions with a grain of salt and verify everything before accepting it. As always YMMV etc etc. In an effort to convey an understanding of the principles to readers who have down little or no previous investigation in this complex area, my descriptions/analogies have been rather simplistic, but hopefully have remained correct.