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Millercarbon's Mega Vibration Control Journey

Vibration control is such a huge, and hugely important, topic it deserves a thread of its own. There was a time I thought it nuts to say such a thing. In fact I wrote a letter to the editor excoriating them for wasting my time on the goofy idea that clamping components between shelves could have any effect on sound at all, let alone be worth spending good money on a rack designed to do just that. This was the Michael Green rack, and thanks to my closed mind and dismissive attitude I never did bother to try and find out for myself if there was anything to it.  

Important Lesson Number One: Don't be so quick to dismiss things just because you can't understand how they could work. 

Couple years later unpacking a McCormack DNA1 amp the Owner's Manual says the included spike can be used to improve sound quality. Well now. As crazy as it still sounded this time its Steve McCormack, and he's already given me the spike, so what do I have to lose? Much to my surprise it did indeed improve the sound. Not a lot. But definitely more detail, clarity.  

This is very early 1990's. There is no internet. I know precisely zero audiophiles. Until stumbling upon this one guy at work who says oh yeah and put your CDP on a phone book, and another one on top. Which sounded even crazier but the guy was serious and this being the 90's we all had phone books laying around so I gave it a shot. This time it was only the most barely perceptible improvement, but it was there. If you really listened for it. So not much. Then again, free. Wrapped some fabric around it, ran the CDP like this for quite some time. 

Around this time I'm shopping for components for my new listening room when this guy is more excited about something called Black Diamond Racing Cones than the amp or whatever he was trying to sell me. So I get 3 of these things and they're so much better than the phone book its hard to believe! Well, okay, it was a phone book. Got to compare against something, right? 

These Cones are so good I take them to this Seattle audiophile club and show them around all excited and.... nobody cares. Except this one guy who goes on and on about how he has tried phone books, tennis balls, racquet balls, styrofoam, cones, spikes, on and on everything under the sun, he's tried it all there's just no way he's gonna be impressed- he makes this very clear to me- but okay you're the new guy let me borrow em why not. But they're not gonna work. No way. 

Next day this guy calls me up gushing going on and on how great these are what are they again where did you find em how many can I get? I actually wind up becoming the Washington State distributor for Black Diamond Racing selling Cones, Shelf, all of it. This guy winds up like me, pretty much everything on BDR.  https://systems.audiogon.com/systems/8367  

A lot of what I knew about vibration control back then was based on my own experience with BDR, and learning from owner DJ Casser. This resulted in what became my guiding principles of vibration control: Mass, Stiffness, and Damping.
128x128millercarbon
oldhvymec
5,101 posts
 

turnbowm242 posts11-06-2020 6:48am@millercarbon - You never answered my question regarding SR, but I think the answer is rather clear.
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If you read he did  answered you, the one time he will. You got your shot across the bow, and he sunk your row boat... :-) 

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Vibration / resonance are two different things.. Most speakers made with single and double layer 3/4 MDF, just won’t cut it.. HDF and panel breaks to control and tune the enclosure. You can’t have a thin light box. I found the more the enclosures sound like green concrete, laying on the ground, the easier it is to make the enclosure GO AWAY.. I’m not kidding at least 50 lb a foot for the enclosure. THEN vibration is not as big an issue, for the speakers drivers. Think about the enclosure shaking and a Voice coil trying to move smoothly through a very tight cylinder... Vibration is a driver killer in the long run... 

Vibration due to VIBRATION. BASS, making stuff shake... OK simple answers. I studied the mass loading thing. Interesting indeed!! It still has the same effect as a making the cabinet (enclosure) out of a better dampened cabinet material to begin with.. Aluminum, will ring like a bell, but cast the stuff, add fluff.. one great sounding material...Add 1 layer of rubber (silicone) between 3 layers of 3/4 mdf...Works good...

For my TT stuff you have to have good isolation from the sound in the room and from the vibration it is making... BOTH help a lot for, my CD players too. I try to keep tube amps, isolated pretty much.. SS not near as much. I find less distortion, clearity, and longevity increased for the actual valves..

I lift cables because it’s easier to clean.. really, I lift and separate cables though, I won’t let cables touch AT ALL, if they have to cross, 90 degree.

If I had it my way.. an Ampa style music room, no top, no sides, and carved out of a mountain side.... There would be NO vibration... Bring your own seat cushion, its gonna be a tough set without one...

I set up and listen, for sometimes a year, then tear down inspect, change as needed.... always a little change or something I been working on..

Regards...
turnbowm
353 posts
 
oldhvymec1,338 posts11-06-2020 8:19am
"turnbowm242 posts11-06-2020 6:48am@millercarbon - You never answered my question regarding SR, but I think the answer is rather clear.

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If you read he did answered you, the one time he will. You got your shot across the bow, and he sunk your row boat... :-)"

MC made NO mention of SR whatsoever in his reply to me. That aside, being a Navy veteran I enjoyed your nautical humor. Thanks!
millercarbon's avatar
millercarbon OP
12,531 posts
 
Thank you, oldhvymec, made my day. How right you are.

mahgister-
The impactful results of resonance/vibration controls embeddings is very audible....The problem is the way to reach results is a complex problem...

Yes indeed we are on the same page. As you well know. And as will become even more clear as the story unfolds.

We left off with the turntable stand. https://systems.audiogon.com/systems/8367 This was based on everything learned in those two years of testing out what was around at the time. Remember again, have to keep reminding people, this was before the internet. Now you just change your browser from Goolag to one that actually works and find what you want in no time flat.  

At this time, based on everything tried, I had come up with my own working principles of vibration control based on stiffness, mass, and damping. Stiffness in materials gives a faster sound. Mass improves bass extension and impact. Damping lowers background noise. Each of these also has its downside. The trick is like mahgister said to find the right balance.

What I came up with was solid concrete, with a sand bed cast into it, and granite on top. The idea being the sand will damp the stiff and massive concrete and granite.  

Seemed like a good idea until the granite came and holy crap granite rings like a bell!

Important Lesson Number Two: Shape matters! A block of aluminum seems pretty inert, an empty aluminum can doesn't ring either. But what's a tuning fork made out of? Aluminum. And those things ring and ring like forever. So shape is really important too.

Thinking fast, what if the three solid concrete shelves are bolted solidly together? Take ABS, fill it with concrete, with bolts cast in so they screw into matching threaded inserts in the shelves. Super strong, stiff, and massive, now also damped by virtue of the bolted together columns. When bolted together its almost like one solid block of concrete.

It worked! The whole thing bolted together and with the granite on top weighs in around 700 lbs. Its pretty dead too. The sand bed however turned out totally inadequate to control the granite ringing. You could hit the granite and hear it, "ting". Not "tiiiiinnnngg" like before. So better. But still.... So I got another machinists plate and put it on top of the first one, with a layer of Blue Tack in between. A sort of reversible constrained layer damping. That's why there's granite on top of granite here.

This by the way is exactly what mahgister is talking about. No one material by itself has exactly the perfect set of properties we want. By trial and error, and with a lot of serious listening, they can be matched together to get whatever balance of sound we are looking for. Or close as we can, given limited time and money. ;)  

turnbowm
353 posts
 

millercarbon OP6,439 posts11-05-2020 6:50pm
"....Okay so here's how it works. You take a jab like that, turnbowm, boy do I hope you got your money's worth. Because congratulations, you made the list. This is the one and only response from me you will ever get.  I am my own moderator, and you are banned. I see your name, I stop reading. Got it? Good....."

Knowing that I will no longer be a recipient of your condescending arrogance is like a gift. Thanks, much appreciated! 
millercarbon's avatar
millercarbon OP
12,531 posts
 
Limited time and money. So everyone knows the rack and everything else we're talking about here is a compromise of some kind.

I'm talking about the rack because that's when I really started thinking seriously about vibration control. Which is funny because even before the rack there was the turntable. Turntables are a study in vibration control! The whole thing is doing nothing but vibrating. Something that now seems almost self-evident, but to me back then (as with a lot of guys it seems) it seemed like all the vibration was coming from the floor, or rack, or whatever. There was almost no thought given to the cartridge, arm, the table itself. Oh well. Live and learn.  

My first table was a Basis 2001. At first it went right on the floor. Then it went on two sheets of 3/4" MDF glued together. With different things, eventually BDR Cones, under the MDF. With a Graham 2.0 arm and Benz Glider I thought this sounded really good!  

For some strange reason I can never quite understand turntables seem to be really mysterious. Maybe because I went with the Basis it never was quite so hard to understand. The Basis arrives disassembled. Its really nothing more than 1" acrylic with some holes drilled, into which you screw four footers, the bearing, and your arm. An awful lot of turntables are to this day nothing more than that: plinth, feet, holes. Okay, motor.

The trick it turns out is in how each of these controls vibration. The Basis used four pods or footers that were little cylinders filled with silicone fluid. Inside that were springs with little paddles that made the whole thing like a sort of shock absorber- spring and damper all in one.  

Looking back, why I did not experiment with different viscosities, or none, is beyond me. Oh well. Live and learn.

Because that was my first hands-on experience with springs, only it wasn't much experience, because I wasted the opportunity to try and learn. Been making up for lost time ever since....

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