Component isolation


Let’s say you’re going to add isolation feet to a component with no moving parts, such as a preamp, phono stage, DAC, amp, tuner, etc. 

Which one is most critical to the extent would get your attention first? 
768e3cdc b761 4131 ab7d b47af0995626zavato
First, anything with a tube.

Next, in order of gain, so phono stage.

TBC, it's a real shame there isn't more research and evidence into vibration and solid state devices. Some gear will be more susceptible to microphonics than other gear just by part selection, construction methods, etc.

That being said, the worst bit of kit I ever had was a cheap phono preamp and it would ring like a bell if you rapped on it.

Much else is probably overblown.
Post removed 
Disregard what Elizabeth said. Each individual component may need very different isolation devices.
Are you asking because you don't want to spend on the devices for all your components or simply curious ?
+1 @inna . Each component may need a different footer or isolation solution. And it usually requires experimentation. 

There are many threads in the archives, some recommending an isolation platform plus footers. In the case of certain components like a TT, it's best to use cones or hard footers to drain vibration into a hardwood platform such as maple.

 
Also agree with @erik_squires . A component doesn't need to have moving parts to cause vibration. There's internal vibration as well as acoustic caused by sound waves.
As stated, anything with tubes needs isolation and sometimes needs damping using a weight or material on the top of the chassis.
And SS components with large torroidal transformers can suffer from vibration. 

Hi zavato

All audio parts are moving. Audio itself is motion as it interacts with the four fundamental forces. This why I like to say vibratory tuning instead of isolation. On this forum you’re probably going to see 4 camps.

1) vibratory tuning

2) springs

3) dampening

4) mass loading

The reason I start my post this way is because it’s easy to lump these together if you are not very experienced in "voicing" your audio signal.

When you start down the vibratory control road one of the first things you’re going to learn is "your audio chain is interconnected". I’m not talking about wire, I’m talking about the Audio Code (audio signal) itself. What you do to one part of your system affects the whole. It affects the whole, because the audio code is a continuum of motion (force interaction). If you look up the "four fundamental forces" it breaks this down. In other words, you’re not so much treating a component as much as you are treating the actual audio signal traveling through the component. If you look at your system as a series of conduits connected carrying the audio signal it’s easier to manage the sound, and that’s what you’re trying to do "manage the sound" (vibration).

There’s a few tips I’d recommend thinking about. First, when you dampen vibrations you’re also dampening part of the audio signal. At first listen you might think things are tighter sounding but after you play a few recordings you will discover you have selectively removed part of the music content and the system will sound strained (smallish squeezed) on some recordings. Second with dampening, what ever your using to dampen with, this material’s character will be introduced to the audio code. This holds true with the AC, electronic audio signal and your acoustics. In audio the phrase "you are what you eat" is exactly what happens. Everything you use as a material with your system adds to the chemistry of the sound you hear.

Another tip. Low mass frees the sound high mass squeeze the sound. The more weight and compressed mass your system has the more squeezed the signal will sound. The lighter mass you have, the more open the sound will be. Both of these can be good or bad depending on how you use them or what you want to hear. Most audio systems to me sound very squeezed so I get rid of as much of the weight and mass that I can to start with. From that point I apply variable tuning to parts of the conduits using controlled mechanical transferring as a means of adjusting the signal.

Others like Geoff Kait will use spring (isolation). He and I kind of have a difference in the absolutes of the term isolation but we both believe in springs, we both use springs. If Geoff comes up he’ll explain his idea on spring control.

So these are just some basics to tuning your mechanics up. Main thing is to keep in mind that the signal is made up of fundamentals and harmonics. Squeeze these harmonics too much and you will squeeze the sound, open them up too much and your sound will become mostly air. Finding that balance can be done to give you a general sound or you can even tune per recording if you want to go that extreme (you’d be surprised how many do).

My suggestion is to explore both tuning a springs and lean away from dampening. However the more experience you gain on your own and from others will help you make your own method work for you. I've used all of the above because I tune for many people besides my own listening.

Michael Green

Damping should be used sparingly or not at all. As Michael states, it does take the air out of the music. IME, lightweight damping may be needed on an enclosed tube component where the cover to the chassis is causing resonance which is picked up by the tubes.
An explanation of one situation.


Well, I don't think the man is asking about this kind of extreme tuning that Michael is talking about. I certainly wouldn't tune for every recording just as I don't adjust VTA for every record but fine tuning the complete system to achieve the best possible compromise is worth the effort and a true audiophile endeavor. But first the system must be complete, both active and passive components. In a sense, there are no passive components, cables and power cords are also very active. How to achieve the system completeness ? Well, I don't have an answer, you got to experiment, to listen and to have audiophile instinct. System is complete when if you insert any new components in it, as good as it might be by itself, the sound you get is off the balance and out of tune, in other words - worse overall even if it might be better in certain aspects. 
I can give an example of how to throw the system off the balance while using exactly the same components in the chain, in this case interconnect cables.
I usually run the signal as follows: from Goldring 1042 cartridge thru Nottingham arm's wiring harness to Acoustech phono stage thru Tchernov Reference MK II cable to Nakamichi 682 ZX deck thru Purist Audio Neptune cables to Redgum RGi120 integrated thru Purist Colossus fluid speaker cables to Michael Green Audio Rev80 speakers. 
If I put Purist Neptune cables between phono and deck, and put Tchernov cables between deck and amp I create out of tune sound which is while still pretty good is much worse than the other way around. Whatever other or additional explanations might be, two things come to mind - first, I interrupt the Purist chain, and second I believe Nottingham's wire and Tchernov wire somehow work better together, so in fact I might do double interruption. When not interrupted those two segments - Nottingham/Tchernov and Purist/Purist work fine. I also have Purist Dominus RevB power cord on the integrated and Purist Aquila on the PS Audio regenerator everything is plugged in.

I’m curious, and I should have mentioned, all gear is solid state
Isolation need not involve damping or lack thereof. The Townshend Audio Seismic products and the IsoAcoustic GAIA's provide isolation only.
Without going into the stratosphere, I always do power amps or integrated amp first, either tube or transistor - no difference. 
That's, after turntable and speakers. Phono stage first will get you nowhere, so will the dac. Preamp maybe but I don't see why start there. Power cords on the amps are also my first move regarding this part of system assembling. Power amps by definition are bad, better start there.
I'm not sure whether anything without moving parts requires isolation. Why would it? Can resonances actually convert into electrical signal? If so, can we hear them?

I know Naim Audio have long employed various isolation strategies to reduce the effects of vibration in their pre-amps but they were almost unique in this regard. I recall that the circuit board on their 32.5 pre was mounted on top a piece of sponge.

@erik_squires, Townshend Audio have purported to provide some scientific evidence to back up their speaker isolation stands. My guess is that the benefits of isolation diminish rapidly with solid state devices where there is a lot less rattling about, and even then any benefits are perhaps only apparent with extremely low level unamplified audio signals (pre-amps or earlier).

Michael Green's post was interesting and I'm tempted to agree with his findings, especially those regarding high and low mass. However, as I'm also tempted to believe in life after death, a little scientific rationale would be most welcome.      

Until then it just remains a matter of faith, nothing to get too hung about. Besides, as @elizabeth  pointed out it's no big deal to experiment with Sorbothane or similar even for those less critical areas.




The signal itself is subject to mechanical vibration. That’s why isolating apparently inert objects results in better sound and why isolating, i.e., suspending cables and power cords results in better sound. Furthermore, objects that appear to be inert actually are not (rpt not) inert. For example capacitors vibrate and transformers vibrate. There is no getting around it. That’s why a wise man loosens or removes the bolts holding the transformer to the chassis and isolates the circuit boards from the transformer and isolates the transformer from the chassis or removes and relocates the transformer.

Furthermore seismic vibration moves the entire building structure so, even if there was such a thing as a completely inert component, which there isn’t, it would still be moving right along with the building’s motion. There’s no getting around it.
Post removed 
I'm not sure whether anything without moving parts requires isolation. Why would it? Can resonances actually convert into electrical signal? If so, can we hear them?

Some parts, absolutely. The ringing I described in the phono stage was most likely due to ceramic capacitors. The physical rapping causes movement inside affecting the distance of the plates to one another.

The problem I have is that we don't really measure how vibration affects solid state appliances, but it could be done.

Speaker isolation and eliminating the motion of speakers is an entirely different beast, and can be very effective. The cause/effect here is simple and clearly audible.

Best,
E

Post removed 
All my audio gear,speakers included, are on my desk beside my computer screen...

There is the mechanical vibration and resonance problem I partially solved with my own device at low cost (quartz feet+granite plate+sorbothane+garnite plate+cork plate+bamboo plate+sorbothane) under my 2 speakers and under the dac and under the amp... I also damped the speakers with concrete slabs 60 pounds or more on top, with some little less slab on top of the dac and on top of the amp... i also glued sorbothane around the cone of the speakers and around the cups of my headphones to isolate the cups...The difference were very audible...The load and the quantities must be determined by listening, because like Michael Green said too much constrict the harmonics much less expand them...

But more importantly than mechanical vibrations and resonance was the noise floor threshold that is too high, in any audio system, if not taking care of +EMI interference of any part of the audio system with any electronic appliance in the house or the neighbourood... The solutions in the market are generally linked to the purchase of some power supply and conditioner or isolator from the computer noise etc...

Filtering the electrical line with active electronic components "clean" the sound but the price to pay is some kind of "reframing" the sound, because it is a trade-off between the component that are introduced that clean and the one to clean...The best solution for me was to use stones and crystals that are passive filtering device with no trade-off, because the floor threshold of the audio grid is not modified by the introduction of new electronical active components, then a net lowering of the total noise floor of the system follows... They are filtering passively... The upgrading effect on the audio line and on the general electrical line of the house was so astounding that nothing I purchase compared to that...The same gear I was not totally satisfied with are now so good that a "real" upgrading is impossible really under 25 thousand dollars … My system net cost is 1000 dollars... And you know what, even if I had this money I am not certain that I would buy that 25 thousand bucks new system,because when you are happy with the music for the first time in your life, you dont feel the need to upgrade...My system is not perfect, but for the price modulo these cleaning methods it is unbeatable...


I read so many forums about audio, I know that most people underestimated completely the vibrations problems, but more than that the most important problem linked with the electro magnetic and radio interference between components equipment from the room, from the house or the neighbourhood.....
zavato: Let’s say you’re going to add isolation feet to a component with no moving parts, such as a preamp, phono stage, DAC, amp, tuner, etc.

Which one is most critical to the extent would get your attention first?

It doesn't work that way. Everything vibrates, everything, and the only way to know which one of your components improves the most is to try different things and find out for yourself.

On that note, this is pure gold:

All audio parts are moving. Audio itself is motion as it interacts with the four fundamental forces. This why I like to say vibratory tuning instead of isolation. On this forum you’re probably going to see 4 camps.

1) vibratory tuning

2) springs

3) dampening

4) mass loading

The reason I start my post this way is because it’s easy to lump these together if you are not very experienced in "voicing" your audio signal.

When you start down the vibratory control road one of the first things you’re going to learn is "your audio chain is interconnected". I’m not talking about wire, I’m talking about the Audio Code (audio signal) itself. What you do to one part of your system affects the whole. It affects the whole, because the audio code is a continuum of motion (force interaction). If you look up the "four fundamental forces" it breaks this down. In other words, you’re not so much treating a component as much as you are treating the actual audio signal traveling through the component. If you look at your system as a series of conduits connected carrying the audio signal it’s easier to manage the sound, and that’s what you’re trying to do "manage the sound" (vibration).

There’s a few tips I’d recommend thinking about. First, when you dampen vibrations you’re also dampening part of the audio signal. At first listen you might think things are tighter sounding but after you play a few recordings you will discover you have selectively removed part of the music content and the system will sound strained (smallish squeezed) on some recordings. Second with dampening, what ever your using to dampen with, this material’s character will be introduced to the audio code. This holds true with the AC, electronic audio signal and your acoustics. In audio the phrase "you are what you eat" is exactly what happens. Everything you use as a material with your system adds to the chemistry of the sound you hear.

Another tip. Low mass frees the sound high mass squeeze the sound. The more weight and compressed mass your system has the more squeezed the signal will sound. The lighter mass you have, the more open the sound will be. Both of these can be good or bad depending on how you use them or what you want to hear. Most audio systems to me sound very squeezed so I get rid of as much of the weight and mass that I can to start with. From that point I apply variable tuning to parts of the conduits using controlled mechanical transferring as a means of adjusting the signal.

Others like Geoff Kait will use spring (isolation). He and I kind of have a difference in the absolutes of the term isolation but we both believe in springs, we both use springs. If Geoff comes up he’ll explain his idea on spring control.

So these are just some basics to tuning your mechanics up. Main thing is to keep in mind that the signal is made up of fundamentals and harmonics. Squeeze these harmonics too much and you will squeeze the sound, open them up too much and your sound will become mostly air. Finding that balance can be done to give you a general sound or you can even tune per recording if you want to go that extreme (you’d be surprised how many do).

My suggestion is to explore both tuning a springs and lean away from dampening. However the more experience you gain on your own and from others will help you make your own method work for you. I've used all of the above because I tune for many people besides my own listening.

Michael Green


This is my chance to apologize to Michael Green. Because way back 30 years ago I was so sure stuff like this was bunk that I wrote a letter to the editor telling him to quit wasting my time with these silly Michael Green racks.

I still never have tried one of his racks. But I know everything he says above is right and true, because not long after writing that letter I began trying and listening and learning and all that experience the last 30 years says what he wrote above is spot on.

Including especially the part about tuning. Because while my feeling is high-fi dom as a whole has moved too far off to the fast and light end of the spectrum, that's fine. If that's what other people like that's just fine. Because with that same understanding I'm able to make my system sound spine-tinglingly fabulous, and that's what counts. Because it means you can too.

So sorry bout that, Michael. And thanks!


Michaelgreenaudio
Others like Geoff Kait will use spring (isolation). He and I kind of have a difference in the absolutes of the term isolation but we both believe in springs, we both use springs. If Geoff comes up he’ll explain his idea on spring control.

>>>>>Springs by themselves do nothing. They need mass to perform. The isolation devices that are based on Springs or airsprings employ mass to produce a low pass mechanical filter. It’s called mass-on-spring isolation. The objective is to achieve a very low resonant frequency for the isolating system to reduce the transmission of vibration as much as possible to the item being isolated. For an iso system with a resonant frequency of 5 Hz quite a bit of very low frequency vibration will still be transmitted since the low pass filter is relatively inefficient for those frequencies and will allow ALL frequencies below 5 Hz to be transmitted.

Very low resonant frequencies can be easily achieved using this method. “Mass-on-spring” isolation is the primary method of seismic vibration isolation for audiophile iso devices and for LIGO, the project to detect and observe gravity waves, which requires extreme isolation measures to reduce background vibration to the absolute minimum, isolating the super sensitive optics from seismic vibration.

My Nimbus Sub Hertz Platform, Townshend Seismic Sink, Vibraplane, Ginko iso stand, Vibrapods, bicycle inner tube, Gaia isolators and other speaker isolators - they’re all mass-on-spring devices. Anywhere a spring is used between object A and object B less vibration will be transmitted. You could even call it a damper.


Don't tease me, bro! The Nimbus Sub Hertz Platform is no longer available! http://www.machinadynamica.com/machina24.htm
Can't imagine why this didn't catch on.
Things evolve, Mr. Smarty Pants. Unlike some people, bro’.
Don't tease me, bro!
The Nimbus Sub Hertz Platform evolved into,.....?
“If I could explain it to the average dude they wouldn’t have given me the Nobel prize.”
Frank Van Alstine was recommending a paving stone sitting on an under-inflated inner tube as a turntable isolation platform way back in the mid-80’s. I believe the idea was already very old even then, dating back to the 1950’s. The early, WWII-generation engineers and audiophiles got a lot right.
geoffkait-
“If I could explain it to the average dude they wouldn’t have given me the Nobel prize.”


Oddly enough, no Nobel Prize winner ever said that.

On the other hand Richard Feynman, who really did win a Nobel Prize, actually did say, "If you can't explain something in simple terms you don't understand it." https://kottke.org/17/06/if-you-cant-explain-something-in-simple-terms-you-dont-understand-it



Or as the T-shirt says : "I can explain it to you but I can't understand it for you."
Hello all,
As a manufacturer of pneumatic isolation devices (feet), am I permitted topost our website which contains pertinent isolation/vibration information, and an informative White Paper? If so, can our technical director also join in on this discussion? Thanks in advance for your feedback and consideration.
I've never seen a convincing argument that vibration isolation effects electricity. Sure, turntables and speakers, but not sure electronics goes beyond the "seems like" rationalization.

millercarbon
418 posts
03-17-2019 3:17pm
Don't tease me, bro! The Nimbus Sub Hertz Platform is no longer available! http://www.machinadynamica.com/machina24.htm
Can't imagine why this didn't catch on.

I'm with you. I have three of them and they all work great!!!  ;)))

JD
Hi all,

This issue of vibration resolution and the science behind it can get overwhelming and out of proportion with the cost of mitigating it in my opinion. I certainly may be naive in this regard but I have used a cork mat on my turntable, the little cork or cork-like inserts in Shunyata steel feet boxes for small devices, and even wine bottle corks that I have cut in half length-wise to use under components. More recently I have also used Vibrapods. At only $24 for a pack of 4 Vibrapods, I think it has hard to go very wrong. At best, I have solved any vibration issues I may have and can perceive. At worst, it’s a good start and not expensive. Leaving to ask what would be the incremental benefit of my expensive vibration resolution solutions. 
**Leaving to ask what would be the incremental benefit of *any* expensive vibration resolution solutions.
Any expansive vibration solution is certainly not worth it,because the money invest would be more useful at any other link of an audio system... I eliminate audible vibration at low cost in my system...


The greatest underestimated problem and more difficult to solve atlow cost is cleaning the electrical line and the audio line system...
I try too play it safe and do everything including speakers, though don"t buy expensive feet etc.On another note the picture of your ? sure is hot!!!
Michael, you say that," ... when you dampen vibrations you’re also dampening part of the audio signal." In my system, parasitic resonances (all resonances are a form of vibration) such as those excited in the tonearm, are not part of the audio signal. So I damp them out. Don't think you can have thought this through.

You also say, "Another tip. Low mass frees the sound high mass squeeze the sound. The more weight and compressed mass your system has the more squeezed the signal will sound. The lighter mass you have, the more open the sound will be." Don't quite know what you are getting at here. Do you really mean that a high mass platter will "squeeze the sound?" If so, what do you mean by 'squeeze'? Is this a frequency effect? And what on earth is a 'compressed mass'?  What is being compressed, and what force is doing the compressing? 

Good questions and comments Terry. Damping the vibrations in a component, vibrations that the component may potentially add to the signal, is not "dampening (sic) part of the audio signal." Where in hell did THAT idea come from?! This idea that components themselves should be considered musical instruments, free to resonate, is SUCH an anti-high fidelity concept. Components should simply reproduce the sound of instruments (and voices) contained in recordings, having or adding no sound of their own. My God, that’s the first truth of hi-fi!

"Low mass frees the sound" and "High mass squeezes the sound" are just overly-simplistic bumper sticker slogans. Audio engineers don’t think in those terms. The high-mass VPI turntable platters (the purely stainless steel, the stainless steel/Delrin, and the aluminum/lead/Delrin) sound MUCH better than the low-mass acrylic platters. My Townshend Audio Elite Rock table has a plinth of a metal frame filled with bitumen pads and plaster-of-Paris, built that way so as to be non-resonant. Designer/engineer Frank Van Alstine suggests lining the inside surfaces of the wood bases of suspended subchassis designs (Linn Sondek, Acoustic Research, etc.) with modeling clay for the same reason. If high mass achieves low resonance, that’s a good thing. Of course, that too is an over-simplification, as there is the matter of resonant frequency, Q factor, etc.

Hi millercarbon, thanks!

When I got into the HEA part of this industry I did so with some good advice from the guys who I worked with in the studios and on the road. I was known among some for coming in, doing my thing and quietly staying off to the side while the sessions went on not getting involved in the debates, credits, money or theory building. The advice was "never change that rule of mine". It's served my goals well and has given me valued friendships and a clear understanding of what it takes to become a long term standard.

We have a wonderful industry and hobby, all the way from instruments to the ear, and I have tried to be in every position of "Doing" I could have so I can be a forever student of this passion. The only way I knew to do this was jump in, do, and learn for myself without being influenced by talk minus the doing. There's a completeness about doing something for ourselves and if we do so in time the truth makes it's way to us. It's a process that may happen in a moment or one that may take a lifetime but truth itself is never false, and the learning of it is truly a matter of doing.

So for me, when people say that's not the case, can't be true, he's full of it, wow that made an amazing difference or whatever suits their proclamation, I know if they have really done for themselves they know. And as important, if they haven't done for themselves they may never know what has been waiting for them to yet be discovered.

Audio is not a world of assumptions, neither is audio recording and playback. Audio is a science that we will either do or not do.

Again thanks, it means a lot to me. Not that I was right or wrong, but that you saw I was a student of sound just like you with the same goal and passion! all my best

mg

Hi Terry9

you said

"Michael, you say that," ... when you dampen vibrations you’re also dampening part of the audio signal." In my system, parasitic resonances (all resonances are a form of vibration) such as those excited in the tonearm, are not part of the audio signal. So I damp them out. Don't think you can have thought this through."

As I've said above, I'm a do it guy. If your ears have given you a different result of course you have to be true to your ears.

mg

bdp24

"Components should simply reproduce the sound of instruments (and voices) contained in recordings, having or adding no sound of their own."

Wouldn’t that be nice! Or our ears, or our rooms, or our brains, or our locations, or our planet on it’s revolving. Or our orbit...and on and on it goes.

the variables buddy, don't leave out the variables

mg

tt1man4 posts03-17-2019 8:47pmHello all,
As a manufacturer of pneumatic isolation devices (feet), am I permitted topost our website which contains pertinent isolation/vibration information, and an informative White Paper? If so, can our technical director also join in on this discussion? Thanks in advance for your feedback and consideration.

>>>>>Go for it! Don’t be shy.

kingbarbuda
14 posts03-17-2019 9:40pm**Leaving to ask what would be the incremental benefit of *any* expensive vibration resolution solutions.

>>>>>Generally, the two determining factors for isolation device performance are resonant frequency Fr of the iso device and number of directions of isolation (degrees of freedom). Thus, the spring rate of the spring should be as low as possible for a given weight of the component. Very Stiff Springs 🏋🏻‍♂️ must obviously be used under very heavy amps, speakers and turntables, otherwise the component will topple over due to insufficient lateral support.

As I already pointed out a Fr of 5 Hz will result in transmission of 90% of vibrations with frequency of 10 Hz, whereas if the Fr can be reduced to 2 Hz the percentage of transmission for 10 Hz vibration can be reduced to 50%. The low pass filter characteristics of mass on spring isolators provide very low transmissibility for frequencies greater than 20 Hz. But obviously there’s an incentive for trying to achieve very low Fr. My Nimbus Sub Hertz Platform was the first audiophile iso stand to provide six degree of freedom isolation. By contrast, most audiophile iso stands provide one or two directions of isolation, the vertical direction 🔝 and horizontal plane 🔛.

There are six directions of motion for any object, including three rotational directions around the x,y, z axes, respectively. Forces in rotational directions are usually caused by Earth crust motion that is analogous to shaking out a carpet or a wave 🌊 passing under a boat 🚣‍♀️.Thus, the ideal vibration isolator addresses all 6 directions. But the more directions addressed by an isolator the greater the complexity and cost, generally speaking. A combination of mass-on-spring isolators and roller bearing assemblies can provide isolation in most of the six directions, for example.

There are additional factors involved in effective vibration isolation, such as method of mounting the component on the top plate of the iso stand, method of mounting the iso stand on the floor or rack, and method of reducing “residual vibration” on the top plate of the iso stand. The geometry of the spring or airspring is yet another variable. A bicycle 🚲inner tube, for example, has a very non-ideal geometry. And the airspring used in my Nimbus Sub Hertz Platform had ideal geometry, whereas the air bladders used in some iso devices are not at all ideal geometry-wise.
The room is full of vibrations -- that’s what sound is. So, I’m not a true believer in vibration control, mostly because there’s no such thing IMHO. Tube dampers will make a difference with microphonic tubes. And you want something to stabilize your turntable from external shocks. But other than that, it's a waste of money.
millercarbon419 posts03-17-2019 7:25pm
geoffkait-
“If I could explain it to the average dude they wouldn’t have given me the Nobel prize.”


Oddly enough, no Nobel Prize winner ever said that.

>>>>Really?

“Hell, if I could explain it to the average person, it wouldn’t have been worth the Nobel prize.”
>>>>>Duh! 😳

Kind of a fun thread for me, cause while posts are going up I am also on my split screen walking people through tuning their components in real time.

mg

Doug Sax had the best method of determining the transparency of any given piece of equipment---the bypass test. He would compare a live feed from his studio with the sound of the same signal passing through the device being evaluated. Any difference between the sound of the two was the component adding it’s own sound to the signal---aka distortion. The idea of high fidelity is to minimize that difference. Hi-fi components aren’t musical instruments, they reproduce them. The sound of musical instruments and voices contain timbres and textures; a hi-fi system should have none of it’s own. In fact, the less it has, the better able is it to reproduce that of instruments and voices.

It’s a very old dilemma: Do you want your system to reproduce the sound contained in recordings---whatever that sound may be, or do you want it to create sound you "like", regardless of the sound contained in recordings? J. Gordon Holt, the pioneer of subjective reviewing, argued for the former and against the latter. Harry Pearson’s standard was what he called, as we all know, the absolute sound---the sound of acoustic instruments in a real space, like a concert hall, cathedral, or even recording studio. But that construct relies upon the assumption of recordings containing such sound, waiting only for it to be reproduced. Very few recordings contain pure acoustic sound in a real space (in Pop music, virtually none do), yet Harry and his believers continue(d) to evaluate components based on their ability to create sound like that heard in those real spaces.

That is not so different from Amar Bose designing a loudspeaker that mimicked the 11% direct / 89% reflected sound heard in concert halls. That is imo an inherently flawed concept (recordings made in those spaces contain the direct and reflected sound; to play them back on the Bose 901 doubles the effect. For Bose’s concept to work, recordings would need to be made in an anechoic chamber). So imo is the notion of a hi-fi system itself being approached as a musical instrument, "tuned" to one’s liking. Minimizing the sound added by the system, on the other hand, is a noble pursuit. A hi-fi system (and perhaps I ;-) should not editorialize. The sound of the listening room is itself, of course, part of the system. Perhaps the largest part, along with the recordings. Minimizing the deleterious contributions of the listening room is imo the biggest challenge facing music listeners.

Guitarists who play in more than one tuning often have multiple guitars on stage, one (or more) for each tuning. They don’t play one guitar, retuning it for different songs. I find it hard to believe many here have any desire to re-"tune" their system for each recording they want to listen to. Am I mistaken? Don’t most of us want a system that makes ALL recordings sound as much like what we think music does (or perhaps should)?

I'm sure as time goes on some of those Tunees will be coming here to share their experiences. When they do you can ask them directly. As for me I'm here to help them get started on their journey and design tools, where they take it is up to their own passions bdp24. While I listened with both JGH and HP we spent our time tuning and often making fun of the HEA. So my take on my friends may have also been different from yours.

as always, appreciating your points of view even if they do differ from my experiences

MG

jburidan678 posts03-18-2019 7:34amThe room is full of vibrations -- that’s what sound is. So, I’m not a true believer....

>>>>>Actually, that statement is patently false. I know what you’re thinking, that the sound musical instruments make and the sound speakers make is acoustic vibration. But that is not what the audio signal is. The audio signal in CD players, turntable tonearm wires, preamps, amplifiers, cables is not acoustic vibration or any vibration. It’s electromagnetic waves, an entirely different animal. The problem is that audio signal, the electromagnetic waves, no matter where that signal is in the audio chain, is subject to external vibration - acoustic, seismic, transformer vibration, capacitor vibration, footfall, etc. a common example is acoustic feedback. The cabinet resonance and or acoustic waves from the speakers affecting the audio components via the air and or floor and producing distortion. That’s why isolating components and speakers improves the sound. Hel-loo! 
We hear electricity not original sound, a helpless imitation of reality. Don't fool yourself. Well, that was wrong - fool yourself and keep it that way. But Michael is right, you some guys don't get it. Passing signal causes vibrations that change it, that's the problem. Dealing with external vibrations is easy by comparison.
Thanks Geoofkait for the clear explanation...But Geoff how my stones or crystals act on that loop? I sense that these stones "filtrates" in some way but I dont understand exactly how and why... Do you have an answer?
mahgister103 posts03-18-2019 12:52pmThanks Geoffkait for the clear explanation...But Geoff how my stones or crystals act on that loop? I sense that these stones "filtrates" in some way but I dont understand exactly how and why... Do you have an answer?

>>>>Crystals almost always work via resonance control. Even when they are used around AC circuits or wall outlets, or on circuit breaker panels, they work via vibration control/absorption. Other notable locations for crystals that demonstrate this concept are on room walls and glass windows and doors p, wherever a sound pressure peak occurs, and on top of Tube Traps. Crystals’ principle of operation is due to their atoms acting like mass-on-springs, albeit teeny tiny masses and teeny tiny springs, thus converting external energy to heat.