Vibration Question

The chest is old and crudely made, with a very thick top, and seasoned since sometime in the 1600s. But undoubtedly, you are right, @pindac, there must be effects of percussing a drum-like surface like the top of it. Given that the top of the chest must vibrate somewhat on being struck, how can there be little or no sound revealed by the cartridge? I assume the fact the pods are sitting on spikes is helping decouple them from the surface - a mechanical isolator rather than one resulting from material science.

But I suppose the practical question is whether my ear can hear the resulting vibrations as transmitted to the cartridge, and I’ll be the first to admit my hearing is compromised, having one ear with about 50% sensitivity in it, and the other totally dead. So if I can hear nothing through the cartridges mounted on the built-in mounts on the percussion test, and nothing through the Grado on the pods, I can say that it works as well as I need it to do. The Soundsmith though does give a faint noise in the speakers, presumably because its cantilever and iron is lighter than that of the Grado (I’m making that assumption because it is a low-output MI, and the Grado is not. Probably most of the reduction in output comes from fewer turns in the fixed coils, but that alone offers no advantage over a high output MI: Peter Ledermann must be using lighter iron on the cantilever as well to make his "MIMC" cartridges because that is what makes them sound different). But this is with the pre-amp turned all the way up, and I would typically play an LP with the volume set to 15-20% of maximum. At that level I can strike the chest and hear nothing. Even so, I think you are right, and not just on theoretical grounds, because the Soundsmith sounds different to the way it sounded on the built-in mount. The Soundsmith initially was a disappointment to me when I bought it as a candidate to replace the Decca. It was so neutral and uncoloured (qualities that actually make it a very good cartridge) it did not get my feet tapping. I found I could improve my response to it with various resistive loadings—lots available on the NuVista Vinyl—and then discovered it sounded equally pleasing via the SUT. But it is a different beast on the bipod; there is more bass and this must be related to the new mount, and that must imply some vibration feeding back into the cartridge. Anathema to some, but I like it! If I am 'making a virtue of necessity' as the old phrase had it, so be it.

Thank you for your detailed response, as always.

As stated, the applying a artificially applied ( a strike from a implement or Knuckle) is one that can be reasonably easy to replicate to a very similar outcome by all who do it.

As there are many who do do this, where reports on a outcome are usually ones that are satisfactory, i.e, no noise detected that is of a concern. It does seem it is not too difficult to put measures in place to create an Isolation that is deemed valuable to be in use.

The point of interest, I extended into, was that there are individuals including myself, that have got the desired result from one test type, but have been further investigative with methods to create Isolation.

Furthering investigation and using the usual test method, in my case has confirmed, methods adopted have not been noticeable for their capability to improve the outcome of applying a artificial Kinetic Energy to be transferred.

No sound being produced at he time of a test, is simply that, "No sound being produced at he time of a test. "

There are individuals including myself, that having gone to extended measures to create methodologies to add attempt to improve on the Isolation available. There are follow up reports that are made, that in my assessment share similarities to my own. Where it is stated, that increased attraction is present in relation to the end sound being produced. 

In my case, this is not a fantastical appraisal, the effects are real and notable for the impression that is able to be made. I see no reason why any others report should be considered differently, I see no reason to question their findings, but do understand the influences on individual systems in their own environments, are most likely to be varied on the impact being made.

When seeing a contribution from myself on the subject of Isolation, it will be seen that I am keen to encourage an individual to not 'get of the Bus ' , in their Journey of learning about the effects of Isolation, because one change to a Structure has been noticeable for creating a change they have classed as improved or attractive and wanted to be maintained. 

My experiences are quite simple and Bass notes are a great indicator to where the end sound is being affected.

Bass notes can be Very Loose, Bloated, Muddy, Overbearing, where the condition when not really have a defined cut off, is starving the upper frequencies of their place in the overall range.

Bass notes can be Taut, Sharp, Clean, Adventurous and Complimentary to the Upper frequencies, where their presence are with equally shared influence on the frequency range.

I can't encourage any individual to decide on how the coherence across the frequencies is most attractive to themselves, but as for my own unique preference for listening to the bulk of my recorded music. The more I can experience of the latter description for Bass notes is being resolved, for myself, the tidier the presentation becomes and the musical encounter I most enjoy is being presented.

Then their is the antithesis to the above preference, when I set aside the time to put Chicago Blues on as a replay, I can quickly feel sold quite short, if it does not come with a dosage of colouration from the former description for a Bass note.  Hence, a ESL Speaker Array and its transparency, is speedily swapped out for a Cabinet Speaker Type, the colouration caused by the Cabinet Influences works just fine for myself.       

@pindac The artificially applied kinetic energy is just a very rough indicator. @dogberry relates that thumps make it through with his Soundsmith which means that low frequencies are being transferred to the stylus of every cartridge, but one can ponder why he hears it most with the Soundsmith. What you are referring to as "natural kinetic energy" I call environmental rumble. You have subwoofers. If you can see the drivers, place your stylus down on a stationary record and turn off any low frequency limiting filters. Turn the volume all the way up watching the subwoofer cones. Now you can see environmental rumble which occurs at very low frequencies. Many suspensions, even the lowly LP12 are capable of isolation the cartridge from environmental rumble. Hanging suspensions such as the Sota, Basis, SME and Oracle are the best at it as are the MinusK and Vibraplane platforms. I can not speak for any others. To work a suspension has to have a resonance point below the frequency of the rumble, below 3 Hz is optimal. Done correctly an isolating suspension will also protect from foot falls. Done poorly a suspension can make footfall problems worse, the LP12 being a great example. 

Dear @dogberry : Not polite but anyway: you already did it but are wrong with those 2/separated Pods, no matters what.

and enjoy the MUSIC NOT DISTORTIONS,

R.

As a fact tonearm/TT must be exactly in the same plane/plytnh, external arm pods looks fine and sometimes we use it by necessity but is totally wrong.

@lewm can explain why/it.

Regards  and enjoy the MUSIC NOT DISTORTIONS,

R.

Meanwhile, I shall enjoy both the music and the (pleasing) distortions.