Improving a stone rack

After reading a lot of posts on Nobsound springs, I have decided to give them a try, and have ordered three sets of four. @noromance and @millercarbon helped me make up my mind. Basically I warmed up to the idea that you need a vibration-free stand AND vibration devices. So, we'll see. It will take some time before they arrive.

Thanks for suggestions! The winner so far is grandma's tablecloth!

I will digest and absorb your wisdom. But before we go further: Is there a METHOD to the madness? I mean, I have a suspicion that my stone rack is adding some hardness and extra treble to the sound. Some of you say yes, others no. But what can I do, to test if the hypothesis is true? Maybe the rack problem is very marginal, the hard sound is mainly due to - for example - my somewhat hot tweeters?

Here are some ways I have tested. 1) Hand clapping in front of rack, vs other parts of the room. Result? Not conclusive, perhaps marginally more echo. 2) Listening with a stethoscope on the stone shelves, while playing loud music. Result: cannot hear any clear ringing. They ring when I strike them with a hard object, of course, but not sure if it plays a role with music. However the large volume from the speakers makes it hard to hear whatever goes on in the stethoscope. 3) Varying the basis of the shelves by dampers on the steel supports. Some effect maybe but not a lot, and it lowers stability so again, not sure. 4) Using a variety of footers, including Cerapucs, Walker valid points and large ceramic cones. Some effect, yes, but not so great as I first thought. It seems that the more massive the stone shelf, the less is the extra bonus of good footers. I have some massive stones at the bottom of the rack, and have a tendency to think "i don't bother" with footers there. 5)  Try to measure, using REW. So far, not very helpful.

Other suggestions for method are welcome. I know what some of you may answer. Just throw a huge sound-damping cloth over the whole rack! If I don't hear a clear improvement, the "stone rack is bad" hypothesis can be laid to rest in my case. I will consider it.

My stone rack is made of Larvikite, found near Larvik in Norway, sometimes marketed as Emerald Pearl, or Blue Pearl. It is even claimed to be a Norwegian ‘national stone’ (though it is found also in Canada). I am sure that helps with the sound!

@noromance – yes, Nobsound springs may be interesting. I will first try my big Walker audio Valid points under the preamp, to see if they make a difference. Cerapucs might be even better, but aren’t high enough beneath the preamp to take over from the stock feet. You wrote:

«Are you assuming the shelves are ringing or reflecting the sound waves coming from the speakers, and adding a hardness? While that is valid, it’s not a major contributing factor. I’ve always thought of the challenge being more to do with the relationship between the supporting material and the component itself. It’s at that interface where the support-related sound quality is generated.»

Yes, I assume that the polished glass-like shelf surface plays a role. Somewhat like windows, changing the sound in the room. Although I don’t think ringing is a main problem. I would probably have to play music a lot louder than I do to achieve that. The rack is massive and inert.

I agree that the component / support relation is important. But how can I know if this is the main factor? Rather than reflective surfaces? These should be manifest in two different sound problems, no? In the direction of ‘glassy’ (reflection), and ‘smear due to vibrations’?

Small test result. Walker Validpoints under my preamp, compared to the stock feet, resting on the stone shelf. NB I am not able to do quick A/B comparisons. The preamp is too heavy and my back too poor.

First impression: this is larger. More distinct. But less treble, or softer treble? No. And softer more mushy bass? No not at first, at least. So the first test, plus one for Valid points, but with some unexpected results.

The Valid points are three large and heavy brass spikes that go into damping discs on the shelf. They rise the component and are undoubtedly good for ventilation at the bottom. Sonic results? Not sure yet. But I am sure these footers do something, they do have an affect. Walker have thought about this.

My Einstein The tube mk2 preamp is a one-box design with two massive power supplies in the front, and tubes at the back. A hybrid tube/s state design. The s-state power supplies get very hot, and I guess, these are the main cause of vibration (even with top German design). So I used two validpoints, one under each transformer, in the front, and one in the middle at the back. We'll see, if this works out. Like I said, my first impression was a bit mixed.

Second opinions are important too. Testing Oops, by Fujiya & Miyagi, from their LP Slight variations. A career height I think. With the stock feet it sounds good but bass heavy and somewhat restricted. With the Validpoints, it sounds larger, the timbre is mor convincing, the sound comes to life. Great, but there are some minuses also, some treble stands out too much, and not fully sure about the bass. The validpoints came with some extra tuning discs, placed on top of the components, to cure such ills. Have not tried yet.

@rolox wrote "I have a tempered glass rack that does emphasize the highs and makes everything sound a bit "sterile" and cold." I understand what you mean! Springs (like Nobsound) most probably won’t solve all of that, but hopefully, help reduce it. It is one of my three strategies: damping component vibes (better feet), damping reflective surfaces (shelves and back wall), and damping the shelf bottoms with absorbant mats. I realize I have an Ikea Apetitlig in our kitchen, and should try it.

@fleschler - my VPI hw19 experience was the same. It needed good feet and even a sand box platform. And the springs needed very careful ’just so’ tuning. Interesting that your phono pre is the one where you noted problems. It is the most sensitive component in my rack also.

A learning experience

I have a Meade ETX125 EC astro-telescope on a tripod stand. I use it on two types of foundation: solid ground (outdoors, not very convenient), or a wood veranda (convenient). Guess what happens. The solid stone ground totally outperforms the wood. The image becomes stable and clear, while the veranda image remains blurred and shifts if I move or walk on the veranda.

I wish things were this clear, in audio.

With the telescope, either I see a crater on the moon correctly and in focus, or I don’t.

In audio it is more - maybe this, or maybe that.

If I should create a new laboratory with precision instruments, e g electron microscopes, what would I do? You guessed right. A combination of total stability and well-tuned component damping. Maybe even springs on stone shelves.

@pindac - thanks, I have the original Meade tripod, with no internal damping that I can see. Snake it around the body - you mean the telescope? And - what is IS concept design?

@fleschler - my Aesthetix Io is a tube phono. I think the newest version comes with HRS footers. I cannot experiment with feet under the main unit, due to lack of height in the rack, so it is nice to know that tube phonos can sound best on their stock feet on granite. When I get the Nobsound springs, I will test them under the two power supplies of the Io (there, I have enough height).

One thing leads to another...

@pindac - thanks, interesting, I'll try to check out some more when I go to the cabin with the scope in some weeks. Must also find some way so it can stand outside even with rain. Image stabilisation - yes, even my phone camera has it...

@tomic601 - yes I know J White prefers HRS and I have reasons to believe him. Problem is, unless I change my rack setup, the Io only has space for very short (stock) feet, to get enough ventilation above the chassis.

Constrained layer damping - well, I have adhesive damping mats under some of the stone shelves. Result? In the "yes maybe" direction - no harm, but no big positive effect either. Typical of my attempts to improve the rack.

At last, some clear progress. The record player is clearly critical. A combination of better feet (Cerapucs) and better power cord (Gutwire) seems to be what the doctor ordered. My wife agrees. The effect is as if the artist comes closer, I can hear more of the recording. Very promising, and quite unexpected.

Hi Robert / audiopoint, very interesting, much appreciated. I took a look at your web site also. I agree springs can be tricky, soft materials not good, etc. The idea of metal or alloy under the components seems relevant and should be tested. At the moment I am testing for reflected treble from the rack, using thick wool carpets in front of it.

With Sidsel Endresen and Bugge Wesseltoft: Try, on their Out here album, 2 x LP at 45 rpm, it is like vocalist Endresen is here in my room. On other less good recordings, like Jefferson Airplane: Wooden ships, from Volunteers, and Doors: Riders on the storm, from LA Woman, again from my best (45 rpm) versions, the same effect is there, so even if I can also hear the recording defects, in fact better than before, in the overall sound, they are reduced.

Wool carpet testing - not conclusive. Maybe I prefer the naked shelf. It is not like a big TV screen between the speakers. The rack also acts as a diffusor. I will investigate - some damping of the wall, the shelves, etc. seems ok. And I will experiment with springs (when i get them). But a main impression is that rack damping, footers, and so on, is rather marginal. It works very well by itself. Why? Because the rack is very massive and heavy, and also very stable. Due to the columns I placed in the basement, below the rack. The best low cost investment I ever did.

So far, raising components on footers has worked very mildly positively, in the rack - now trying the Einstein preamp on Walker validpoints and the Hanss player on cerapucs. So far, no dramatic effects, maybe a bit, although subtle. I have some large black ceramic cones to try also (if i find them), and the Nobsound springs when they arrive.

I am testing  Cerapucs under the maglev feet on the Hanss T-30 record player. An improvement? First test: yes, maybe. Slightly more open, detailed treble, and better timbre? So the pucs stay, for now.     

Three sets of Nobsound springs have arrived, so I am testing them under various components. They need to be tuned, so I am taking out some of the seven springs in each foot below the lighter components, so they 'sag' down appropriately. The jury is out. These things take time. It may be, that they work better under my lighter components, like the Teac dac streamer and the Hanss turntable speed control, than the heavier ones like the Aesthetix Io power supplies. Not sure yet. So far, no "wow" type of sound change, but maybe a little bit here and there. Plusses and minuses. Anyway, for a low cost, this is an interesting experiment. Granite stability plus spring type floating of the component. Maybe with a cost in terms of less precise bass but somewhat better mid tone and 3d soundstage? We shall see.  

Yes, good advice. I have them adjusted to a third to half compression. I use three feet under the lighter components (Teac, Hanss) but the Io power supplies need four feet to avoid cabinet stretching I think. I will soon try them under my MA1 amps, three feet should be enough. And yes, of course, directly from the chassis, not below the existing feet. Adjusting feet position to get the best balanced load from the component.

Straight up aluminum - interesting suggestion. Reminds me of how I tried to dampen the 10 kg alu platter on my record player, and found that I preferred "real" to "pleasant" - no damping. So platter mats and DIY platter damping were dropped.

I read somewhere that Duke Lejeune of Audiokinesis wrote about damping - "as little as we can get away with", or similar- in the context of bidirectional speakers, like I have. This type of setup makes the wall behind the speakers even more critical, and the ideal is a well distributed spectral tonality and a proper time delay before the reflected sound from the backfiring drivers. So, damping should be limited, and mixed with diffusion.