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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
millercarbon's avatar
millercarbon OP
12,531 posts
 
If you just want to fill, mix sand with mineral oil, not much just enough to get good and damp so it packs better. Then mix with lead shot and fill your legs. But those legs are stubby, doubt this will do much. 

I have a much better idea but need to know: Are the stands and speakers two separate things or all fastened together?
oldhvymec
5,101 posts
 
Yup they are attached via screws, BUT not glue. I can add between the two. I was looking for a finer furniture look though. I was thinking O-Rings between the two, maybe more than one grove, more than one ring..

I just started sound testing. I was surprised.. Those legs and MDF are pretty good.

The Hardwood TT plinth, though.. MERCY. The oak is so cured and HARD. Pretty noisy.. It took all summer to get the corner seams to settle. They were glued, a blocks added, drilled, clamped and THEN screwed. I almost had to thread the holes.. that was some HARD wood.
Black Oak block and resin. Red oak shins... Stair flats 3 years cured...
1" thick..

Rubber line? What is the name of that sh$t, that you paint on the inside of speaker cabinets... Ceramic paint? Can’t remember... BOTH. Paint and rubber, or silicone paint? Is there such a thing? THE cost... What about that spray stuff for fixing leaking gutters, or holes in boats... That stuff... Gotta be silicone.

Chicken feedin’ time...

Regards.
millercarbon's avatar
millercarbon OP
12,531 posts
 
Great, what I was hoping. So here's my idea: springs between the speakers and the stands. Don't run! Do it like I'm gonna say and they will look almost exactly the way they do now, BUT they will sound a lot better and no more problems with the stands. 

First get one set of Nobsound springs for every TWO speakers you want to do. One set will do 8 corners. You can do other springs but that will mean a lot more work for hardly any money saved.  

Cut holes in the stands at the corners where the speakers will go. Hole saw or router. If the stands are as thick as they look you can router them out deep enough and just drop the Nobsound springs in. You will have to experiment to find the right number of springs. Then cut the hole depth just right and the speakers will float on springs with only a barely visible space just above the stands.  

You do not need a lot of space since the springs only move microscopically when playing music. It will just take a bit of trial and error to get them level at the right height. The springs will pretty much take the stands out of the equation, especially if you put some furniture felt stick-on thingies under their feet.  

With those speakers you will probably only need 3 or 4 springs per corner, meaning one set of Nobsound will do 8 corners. The springs fit snug into a 1/4" hole. Could hardly be sweeter. 
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millercarbon's avatar
millercarbon OP
12,531 posts
 
Perfect timing, I was just getting to springs. This was a real hard sell for me. Rixthetrick had some pretty good arguments that made me think. Max had some very compelling videos that made me think even more. But thinking has gotten a lot of guys including me in trouble. Only one way to know for sure. Rick was very generous and found me the right springs on eBay for me to check it out.

Not any springs will do. They do need to be sized for the weight of the component. Its kind of like what John is saying above, there's always going to be a resonant frequency and you want it to be very low ideally according to Townshend around 2Hz.

I still was skeptical. It just seems a speaker on springs, when the cone moves one way the whole loudspeaker is going to move the other way, and there goes your dynamics and transients.  

But unlike the few others who never acknowledged these problems both Max Townshend and Rick did admit this does happen. Because, physics. Kind of silly when people try and deny physics. (See: using just one sub.)  

What I was missing though, and what engineer Max points out, is that yes you do lose a tiny amount to that but you gain something much more valuable- a huge reduction in ringing.

Ringing is the term for when the whole system is set vibrating and continues to vibrate long after the transient signal that started it all. Ringing is why we want speaker cabinets to be extremely solid and inert. But then we put them on a floor that is anything but. Then we make it worse by using spikes to couple the speakers to the floor.  

As we already know the idea of spikes as diodes and vibration being a one-way street is unfounded. Vibrations go both ways. Once the floor starts vibrating it sends those vibrations right back up through the loudspeaker cabinet to the driver.  

At least this is the theory. When it comes to stuff like this I'm pretty agnostic. Too many wonderful theories just don't seem to pan out. My grandmother was from Missouri, the "show me" state, so its in my blood. So I tend to say, nice story. Show me.
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