[andyr]

Hi, Andy,

... wooden vibrations/resonances reach the amp's pcb, trafos and heatsink. So they start to move and that is BAD. ...

Hi, Kyrill,

I'll have to think about what you said in sections - so here is my first Qu regarding what you wrote above.

Firstly, yes, I can understand how if you have a wooden case rather than a metal case then you are not surrounding the electronics with an electron-conducting medium.  Which is a good thing.

However, forgetting this aspect and just considering vibration:

*  if you isolate the PCB from the metal case - by, say, mounting the GK-1 PCB on Sorbothane blocks - then any vibration which is happening in the case itself will be greatly attenuated when passing through the mounting supports into the PCB?  So it will not vibrate very much?

*  if you want to improve matters even more, then you paint damping material (tar, bitumen) onto the metal sheets making up the case?  This will reduce the amount of vibration trying to get through the Sorbothane mounts.

*  it is not necessary to consider trying to isolate a power transformer from external vibrations because it, itself, will vibrate when the AC signal goes through it - IE. you cannot stop vibrations in a traffo??

So you try to minimise these vibrations getting to the PCB.

Regards,

Andy

[kyrill]

Hi, Kyrill,

I'll have to think about what you said in sections - so here is my first Qu regarding what you wrote above.

Firstly, yes, I can understand how if you have a wooden case rather than a metal case then you are not surrounding the electronics with an electron-conducting medium. Which is a good thing.
There is another aspect, that I intuïtively recognise as something that might be true and where the C37 theory (http://www.ennemoser.com/c37theory.html )is based upon. Every kind of material has its own resonance, like every human being has its own thumbprint. Wood has a much more pleasant sounding "Q" than for instance iron or aluminium. Can you imagine a violin made out of aluminium, how this will sound? In the family of metals brass is much better sounding than steel or iron, that is why "warmth" sounding bells are made of copper/brass

However, forgetting this aspect and just considering vibration:

* if you isolate the PCB from the metal case - by, say, mounting the GK-1 PCB on Sorbothane blocks - then any vibration which is happening in the case itself will be greatly attenuated when passing through the mounting supports into the PCB? So it will not vibrate very much?
This will make a more than subtle difference especially in the phono and preamp

* if you want to improve matters even more, then you paint damping material (tar, bitumen) onto the metal sheets making up the case? This will reduce the amount of vibration trying to get through the Sorbothane mounts. Absolutely, that is what I do next to using silicone paste as the damping layer between  heatsink or pcb and (wooden) enclosure

* it is not necessary to consider trying to isolate a power transformer from external vibrations because it, itself, will vibrate when the AC signal goes through it - IE. you cannot stop vibrations in a traffo??
No you cannot damp it more but they are filtered out (as much as possible) in the PWS, but the external induced gremlins still remain

So you try to minimise these vibrations getting to the PCB. as much as possible. BTW as much as important (it all ADDS up) is to get rid of the gremlins coming out of the elektricity net into the trafo. If the current out the wall socket would be water you wouldn't dare to drink it, it wouldn't even look transparent And thàt is what the music needs, details and depth coming out of "the blackness of transparency"

Regards,

Andy

[Malcolm Fear]

I think Larry tried suspending his GK-1 board, to isolate it from the transformers. I don't think it worked, due to the stiffness of all of the wires that go into the board.

[andyr]

I think Larry tried suspending his GK-1 board, to isolate it from the transformers. I don't think it worked, due to the stiffness of all of the wires that go into the board.

I think that's correct, Mal,

the rubber bands didn't work ... but I seem to remember he decided to mount his traffos on sorbothane blocks.

That's why I decided to do the same PLUS mount the PCBs on sorbothane too.

Regards,

Andy

[kyrill]

In search of operational perfectness.
If I reread the posts I must smile about it if I shift my mental position as areader.

What a nonsense. These people are convinced that a butterfly in China will effect the weather in Europe!.

It started so many many years ago to search for everything that is operable, which can be done, to improve the sound, to make it more real.

A phd  lady, one of the writers in TAS claimed that  reversing the leads to the AC current in the wall (prim. windings of the trafo) could make a real perceptable difference. Many ridiculed her, not HP.
But the problem is you can hear it. My wife can hear it better, even my childeren.

So I stopped being logical in the first place, and put "logics" directly second.
Now I do use cotton shoe laces around my naked internal wirings and I am thinking of putting a layer of silicone paste (kit) over the non active components and pcb. But very difficult to peel away if it doesn't have the anticipated effect.

the diëlectric constant of air around a conducting object is the best sounding, than things like wood or cotton, than teflon, and so on. But what is this value for silikonen kit/paste? Maybe it is the worst and I cannot find a clue on the web

BTW this was a nice read but basic http://www.geocities.com/rjm003.geo/rjmaudio/twk_one.html

[andyr]

...What a nonsense. These people are convinced that a butterfly in China will effect the weather in Europe!.

 ...

Kyrill,

Please, what do U mean by "What a nonsense. These people are convinced that a butterfly in China will effect the weather in Europe!"?

I'm afraid I don't follow the relevance of your comment to what has been discussed before.  In English, we call this a "non-sequitor" ... yes, I know, a good ol' Latin term!!

Secondly, your comment "A phd  lady, one of the writers in TAS, claimed that  reversing the leads to the AC current in the wall ..."

- well, this was the famous and much regretted (ie. we regret her passing!) Enid Lumley. She wrote a whole heap of way out yet really thought-provoking stuff.

In the US, it appears that because of the way their AC power is set up, reversing the mains leads to a component CAN make a difference.

However, my understanding is that this makes no difference in Oz; now, we follow the British standard in this respect but maybe "the Continent" (as the British so quaintly say!) is different??  You are saying that it does make a difference in the Netherlands?

Regards,

Andy

[kyrill]

Hi Andy

I said : if I shift my mental position, then I could "sink into" another kind of reader.  And
he says: "What a nonsense.."

Ah you have a better memory than I can recall.. Yes she was Enid Lumley, didn't know she moved away from us

Well,  in the Netherlands I can hear a difference like my family, like my neighbour. Even weirder, I have a huge (3.2Kwatts, weights >50 kilo's) so called  balanced galvanic separated power transformer for my audio line. +115V and - 115V together 230 V..It is : hearable with that config too

[MikeC]

Andy wroye:

Please, what do U mean by "What a nonsense. These people are convinced that a butterfly in China will effect the weather in Europe!"?

I'm afraid I don't follow the relevance of your comment to what has been discussed before. In English, we call this a "non-sequitor" ... yes, I know, a good ol' Latin term!!

It is a premise of chaos theory, otherwise, "sensitive dependence on initial conditions". For example, if you put a drop of oil on the apex of a large smooth ball, in which direction will it flow? In other words, an extremely small change in initial conditions can effect a very large net outcome change. I think Kyrill is saying that he saw the light after he decided to renounce the old logic and embrace the new.

See James Gleick - Chaos: Making a New Science http://www.amazon.com/exec/obidos/tg/detail/-/0140092501/qid=1089123487/sr=1-2/ref=sr_1_2/104-1311509-6518327?v=glance&s=books .

Cheers

Mike

[Occam]

......
A phd lady, one of the writers in TAS claimed that reversing the leads to the AC current in the wall (prim. windings of the trafo) could make a real perceptable difference. Many ridiculed her, not HP.
But the problem is you can hear it. My wife can hear it better, even my childeren.

Which is why Hugh provided me (and other ASKAphiles?) with a lovely DPDT toggle switch [center 'off', satin black bat and knurled thingies, very retro and cool], that allows this to be done safely, not confusing the fusing, while not adding any extra components.  Anyone who added one of those 3.4 amp tabletop PSs to their Art D/IO knows that with certain components the ability to reverse polarity on the primary is tremendously helpful. While it might not be of similar  importance on Hugh's products, the capability to do this easily, while 'doing no harm',  is a treat.

[AKSA]

Folks,

Paul (Occam) actually acquired these toggles for me;  his saying I provided it to him is actually just the reverse!!

These are a toggle with up-center-down positions.  The center position connects nothing;  the top position, the bottom two sets of terminations, and the bottom position the top two sets of terminations.

This means you can actually wire it for Active to AC1 and Neutral to AC2 on the transformer and the reverse, that is, Active to AC2 and Neutral to AC1.  This gives the option of selecting which phase you wish to lead with in the transformer.

Now, this makes no difference in Australia, where neutral is grounded anyway.  But in the US, a balanced power system is used, with a center tapped ground, and the word is that such a switch makes a difference.

Carlman tried this on his AKSA 100W as an experiment, and heard no difference.  I'm not in the country, so can't hear for myself.  Paul's response is not yet clear to me;  so, the jury's out........

Kyrill, does this answer your PM to me?

Cheers,

Hugh

[andyr]

Andy wroye:
It is a premise of chaos theory, otherwise, "sensitive dependence on initial conditions". For example, if you put a drop of oil on the apex of a large smooth ball, in which direction will it flow? In other words, an extremely small change in initial conditions can effect a very large net outcome change. I think Kyrill is saying that he saw the light after he decided to renounce the old logic and embrace the new.

See James Gleick - Chaos: Making a New Science [url]http://www.amazon.com/exec/ ...

Mike, you Dark Continent resident, you!

Yes, I am fully aware of Chaos Theory.

The reason I wrote what I did was because Kyrill had said "What a nonsense. These people are convinced that a butterfly in China will effect the weather in Europe."

I could understand his reference to the "butterfly effect" but I didn't understand why he said "What a nonsense".

Regards,

Andy

[stvnharr]

Hugh,
I had thought that the Aussie power grid was balanced, and the US was not.   I think I read that in the bptech website sometime ago, and was why it was good to get one of their balanced power conditioners.
Irregardless, can't buy the switching power polarity stuff.  It is alternating current and will work no matter how plugged in.   But it is best in the designed way.
Similarly, one can reverse the leads on one's tweeter and hear enormous changes.   Of course these changes are all bad.   Of course one can think that they are revelations by how the sound is changed.

[andyr]

Hugh,
... Similarly, one can reverse the leads on one's tweeter and hear enormous changes.   Of course these changes are all bad.   Of course one can think that they are revelations by how the sound is changed.

Hi, Steven,

Re. your comment about "reversing the leads on one's tweeter" ... here you are into the topic of absolute polarity vs. relative polarity - about which argument rages (as to whether you can hear it or not).  It would appear that some people are vastly more sensitive to absolute phase than others ... I would tend to think these are people who have trained and refined their hearing bcoz I must say I've never really been able to pick it up.

Just in case U have not come across the concept of ABSOLUTE polarity (or absolute phase, as it is more commonly called) before:

* relative phase is vital because if either one of your right or left speakers has its cables reversed from the other, you hear a strange "echoey" sound and the sound-stage is no longer centred between the speakers.

* similarly, all drivers within a multi-driver speaker need to be "in phase" or you get the same sort of peculiar effect.  (So you can't actually just "reverse the leads on one's tweeter" ... you need to keep the tweeter in the correct polarity relative to the other drivers.  NB: this MIGHT mean that it is actually "reversed", depending on the crossover order being used!)

* however, if all drivers in both speakers are aligned correctly (lets say this means connecting all the red speaker wires to the red binding posts), the reverse also keeps all drivers relatively aligned correctly but now (with the black speaker leads on the red binding posts) the speaker "blows" when it should be "sucking"!!

Hard to describe but basically, if the CD/LP was recorded with the correct absolute polarity, when the singer blows into the microphone, this should be delivered from the speakers as the singer blowing.  The reversed sound (if the speakers have reversed absolute polarity) produces a not-quite-true sound ... again, think of a cymbal "clash" vs. its "reverse".

Trouble is, it seems to be very much "pot luck" as to whether the media is recorded with correct absolute phase or not.  And whether components within your sound chain invert (absolute) phase or not!

Regards,

Andy

[kyrill]

"Kyrill, does this answer your PM to me? "
perfectly

Something about hearing
Well in Holland we do not have balanced power out of the wall.
But now with the powerline "conditioner" (the heavy balanced trafo) i still do hear differences and the rest of the family.

And the neighbour. So how can this be? most people will not hear the difference, even when the ears pick it up, especially when you KNOW  that you will NOT hear a difference because of "old" proofen knowledge (here we have finally the debate again between modernist science and post modernist science). Being aware of something is in most cases not a granted capability, but a learned skill, based on attitudes

For instance in tweaking the  room with digital filters I found out that differences of 0,3 db in certain freq. bands can be heard and differences of 1 db in treble response is a huge difference., not at all a subtle one and changes the nature of the speaker.

My father however could not hear the difference when I reversed R and L with normal music, singer in the middle or classical music.!
Of course his ears picks it up, but he was not aware of it.

[CButterworth]

It is interesting that folk seem to have had bad experiences with their Par-Metal cases.  I bought two cases from their "10 series," a large one for the AKSA 55 N (non-plussed) and a smaller one for a homemade passive preamp.  I found their service was good, everything arrived in a timely manner and stuff wasn't damaged.

True, the cases are utilitarian in nature, but they work and their prices seemed fine.  Yes, maybe in the future, I'll replace the case, or even better, find a really nice piece of wood and build a front panel.

Please don't read this email as an admonishment of your views of Par-Metal, it's just that I found them to be good to deal with.

Regards,
Charlie

[stvnharr]

Andy,
I made a bad analogy between power polarity and speaker phase, comparing apples and oranges.   I hit the submit button too soon.
I am aware of speaker driver's relative phase to each other, and how they really need to all be moving in the same direction at the same time for the music to sound it's best.
Thanks.

[andyr]

I made a bad analogy between power polarity and speaker phase, comparing apples and oranges. ...

Actually, a guy called Clark Johnsen (he now writes for "Positive Feedback") has written a book called "The Wood Effect" in which he makes the claim that getting the power polarity right makes it easier to hear whether your ABSOLUTE speaker polarity is correct or inverted.

I am aware of speaker driver's relative phase to each other, and how they really need to all be moving in the same direction at the same time for the music to sound it's best.
Thanks.

that's RELATIVE polarity.  Why don't you try experiemnts with absolute polarity - although it's such a PITA reversing all the speaker cables.  If your CD player has a "Phase Reversal" switch, it makes this easy.

Regards,

Andy

[stvnharr]

Andy,
Thus far my phase/polarity experiments in speakers have all been by accident.   When everything gets corrected, everything sounds better, no frequencies are cancelled out an missing.
Steve