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In praise of isolation.

Isolation as in components, not personal.

(although, that’s not necessarily bad either)

There has been much praise, and discussion on the forum with regards to spring isolation.

Well, all this praise, caused me to look into how to approach this for myself.

I like to try things before I pass judgment on an idea.

The whole coupling/decoupling thing has been of interest to me for a while.

I get the desire to couple (yeah, I know,,,) as it plants the gear firmly in the ground, and if the base is heavy enough and made of a material that absorbs vibrations, you should be golden.

Then there is the problem of 7.83hz. Nope, not audible, but that doesn’t matter. Anyone who has used a test record to check for tonearm resonance can see quite clearly how an 8hz frequency can make the tonearm shake like a belly dancers belly.

So, decoupling. Springs made logical sense. Except, there was the problem of vintage turntables with their springy/bouncy top plates/platters. That just didn’t seem right.

I made an isolation platform and put springs underneath it. Figured out the proper spring rate and ordered 4 springs to support the 90lbs sitting above them. 
It’s crazy the clear and obvious difference it made. For the nominal price of $100 for the 4 industrial springs, the sonic improvements were off the charts! When coupling, and making changes to the materials used under the TT, and the types of feet used, there was a difference with the clarity of the highs, their brightness and with the bottom end being muddy or lacking depth.

With the springs however, the whole presentation opened up. Everything sounded better, clearer and more defined. Faster, less shrill and I could go on.

Not only am I divorced, but I’m a firm believer in decoupling.

(see what I did there?)

Damned 7.83hz…
perkri
mitch2
4,070 posts
 
@henry53 
With such a low mass load e.g. a turntable and such limited movement in micrometres, the springs will not act as springs but more like a solid piece of metal.
That is why sizing the springs makes the difference between a successful isolation application and..."a solid piece of metal".  Maximum spring capacity, spring constant, and even the spring height and number of winds make a difference.  So do damping and preloading.  For light gear, the springs need to be lighter so they are operating in the mid range of their capacity.

Regarding suspended wood floors vs. concrete floors on-grade, the circumstances are different as the suspended wood floor is already somewhat damped from seismic vibrations that would have a greater impact on the SOG floor, but the wood floor is less stiff and more susceptible to local vibrations from footfalls and other activities.  Resonant frequencies of the two floors will be different and the concrete floor may be more susceptible to ringing.  However, I suspect decoupling with springs would be effective in both situations.  I found springs under my main speakers and subs to improve sonics in my current situation, which has my system on a concrete grade slab. 
perkri OP
909 posts
 
@larry5729 

Funny you should mention that

Was just at an audio show on the weekend, and isoacoustics had a room set up with one amp driving two separate sets of identical speakers. 
One pair had the Gaia footers, the others were on spikes. 
Eyes closed as they switched back and forth between A/B, there was a marked difference. I kept my eyes closed as I didn’t want to see body language as the guy switched with a remote, nor did I want to see lights changing. 
So yeah, much bigger difference than one would expect. Greater transparency, accuracy, detail and bigger soundstage.
Brought a friend with me and I have been selling him on the benefits of isolation - he could not believe these little feet made such a big difference. 
So yeah, it matters and makes a difference 
ghdprentice
7,197 posts
 
I have owned a couple of sprung tables (currently a contemporary Linn LP12) and for over 20 years heavy belt drive (VPI Aries). They could not sound more different. The VPI… heavy bass and good detail… but not as much as the Linn. The Linn has an air about it, sense of space. But something bothered me about it… as if the images were a bit ghosty, like there where faint secondary sounds about the main image… let me be clear… this was very, very subtle. Added to the airiness, I don’t think most people would have noticed it.


I recently got a SRA Ohio XL++2 isolation platform built specifically for the Linn LP12. This has had a strong positive effect on the sound of the table. It has added solidity to the bass, quieted the background noise, and the ghosting disappeared. A very positive improvement.

To me at an intuitive level this makes sense. The isolation platform eliminated really small vibrations that the springs of the turntable were unable to respond to. Effectively making the system act like a high mass sprung system. Regardless of the logic… it sounds much better.
oldschool1948's avatar
oldschool1948
503 posts
 
I have concrete basement flooring and my gear sits on a Butcher Block Acoustics rack on spikes.  The rack is rock solid. I put carpet on my basement listening room floor a couple of weeks ago.  

My speakers are on spikes.  I’m quite happy with my system’s sound. Yesterday, I ordered Gaia III footers and spikes. @perkri - “Greater transparency, accuracy, detail and bigger soundstage” would be nice.  

I’ve been trying to decide between isoacoustics or ingress engineering component isolation products.  I still use stock footers on everything but my Zenith streamer where I use ingress engineering level 3 rollerblocks.

The whole idea of springs is a new concept to me.  Is the application of springs an either or isolation method, or should springs be used primarily with certain components?
perkri OP
909 posts
 
Congratulations on the IsoAcoustics

Hearing the demo confirmed everything for me!
My turntable has springs between a base and the surface of the rack. Ingress roller blocks between the base and the TT. I polished some steel and cut it down as a smooth surface for the balls to roll against under the plinth. 
I feel like a combo like what I did seems to solve a couple of problems. The plinth is coupled to a base via the roller blocks that will help dissipate “local” vibrations. The roller blocks also deal with lateral movement. The springs decouple the whole thing while dealing with vertical movements. Now I just have to sort out the damping. 
The Gaias are a one stop shop :)
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