USB to PC chassis ground ? (noise) - The biggest change ever !

[Nick]

Hey Anthony,

The datasheet of the TI did look interesting but the chip takes a 1.somthing volt clock input so id need to attenuate the dexas output or build a test clock using a module with the correct output.

I guess trying the TI chip on a standard card against an NEC would give a good idea if the TI  shows promise.  Right now its difficult to see how the nec / dexa with todays setting up work applied could get better, but how many times have we thought that before but that's the fun of this hobby.

Your right though, the TI based card needs to be tried.

Cheers,

Nick.

[PeterSt]

Guys,

To me it seems that again you can't hold back of squeezing Dexa related posts into everwhere you see some opportunity.
Did we forget this from my first post ?

So, let's try to let this topic be *only* about what happens to USB Yes or No connected to the PC's chassis.

And please don't come up with a "but what about your floating boat" because this is all 100% related (because necessary to let it work out). What you do is just blundly come up with Dexa stuff AGAIN which relates to nothing. I will honestly admit though that I could not see the real merit from the post of the initiator of this (misery I'd like to call it) :

I needed a PCIe USB3 card for another PC so I took the opportunity to get hold of a Silverstone. I removed the clock from the Silverstone and connected a Dexa coax. With two PCIe cards each hooked up with coax leads for the Dexa a quick swap was now possible for comparison purposes. So I could swap the cards almost in the time it takes to reboot.

The result I can hear no difference at all nothing, zippo, zilch not a sausage (probably that does not translate in to Dutch ha ha).

But it is possible to hear the very smallest of differences in this system (as both Nick and Mani will confirm) - if I move the PCIe Dexa clock just a few inches away from where it is mounted the sound clearly is not as good (presumably RFI affecting the clock).

So there a couple of interesting results: -

1. With Q5=1 if I move the PC Dexa clock to a worse location (i.e. more jitter) it is clearly audible.

2. With Dexa clock applied to a Silverstone I can hear no difference compared with a.n.other PCIe card.

Maybe this is not exhaustive but interesting none the less.

By the way removing the clock from the Silverstone card is a doddle (with 2 soldering irons) it would be my first choice card for applying a Dexa mod - much easier than the other cards I have looked at.

P

I didn't ask because I didn't want to stirr unnecessary, so now I politely will :

Paul, how is this related to the isolation ?

Regards,
Peter

[PeterSt]

This little brochure about Damping Tecniques for Noise and Vibration Control is very instructive http://www.earsc.com/pdfs/engineering/understandingdamping.pdf

At least now you know why many in the beginning were provided these pink pads you see in the picture below. Still have them ? look at the structure ...
Try these (if you still have them (received them at all)) instead of your rubber balls etc; watch the accuracy ....
(do NOT put any feet on/in them; so the NOS1 is to be on them "flat")

Regards,
Peter

[juanpmar]

Peter, I did not get those pink pad with my NOS1. What kind of material is it?

Regards,
Juan

[PeterSt]

Specially layered ESD material. Comes with many electronics as "shipping protection". But the thickness has to be right, the number of layers has to be and the material itself needs a special density.
On the latter matter, we provided a few dozen NOS1's with a white counterpart (not ESC protective but with the layers similarly organized) but the density was not so good as I wanted it to have. This is about it being resistive to denting it (but the back of a pencil in it and the material must come back in original fahsion).

Footers have always been key.
And now I use a waterfoot.
Peter

[juanpmar]

Never tried those ESD (electrostatic discharge?) pads. I guess they are difficult to get. What about those waterfoot, what do they look like?

Juan

[juanpmar]

Footers have always been key.
And now I use a waterfoot.
Peter

Oh, I see you are talking about the viscouse fluid or...was it water? It was water! I don´t know why I thought it was some kind of viscouse fluid...

Juan

[juanpmar]

Some time ago I also used a waterfoot for my self 

http://www.youtube.com/watch?v=nyxrPntmFGg

Juan

[nik.d]

Peter,

I received white pads and can tell they squashed half height, but never mind that for now.
Whats more interesting is that you (at some SW development stage) suggested (which also translates as almost 'commanded')  'remove those pads'.
So I did. And probably most of NOS-ers did. Returned to whatever they used before.

And now with 'aquarium': do you use those pads beneath NOS1 or just 'light & stiff floating plate' of yours.

[PeterSt]

George,

You are confusing with the "remove those 10ct footers which are only there against first scratching". This is in the Install Manual (now and for you USB version too undoubtedly).
So this was not about the pads. The pads were just advised to use ...

And now with 'aquarium': do you use those pads beneath NOS1 or just 'light & stiff floating plate' of yours.

Super special home brew.
So answer : neither.

Peter

[nik.d]

Super special home brew.
So answer : neither.
Peter

Ah, this is developing into commercial product. Capisco.

[PeterSt]

Time for an SQ update ...

Recap of the evolvement :

Windows 8
1. Isolate Silverstone USB3 card. -> Sound got crazy but got me mind crazy.
2. Isolate USB on the NOS1 side (detach black wire from top-right of main PSU). -> Sound would't escape from speaker anymore.
3. Go to Windows 7. -> All back to normal, no distortion from previous W7. Punch. Highs white-harp. Not right (because flavour).
4. Float my NOS1. -> No complaints anywhere.

Notice : I will try W8 again with the floater so it is NOT said at all that this will fail; I just don't know at this moment (but estimate it is way too lean).

All right. Mid Buster eh ? yep, that is what I know now for sure. The best to describe it is that the mid received an accellerator. This should tell all :

Suppose there is this track with such a very fast drum (think rototom). Let's say this rototom is hit once per two seconds or so on some beat. You hear one hit each these two seconds. The track I'm talking about is a kind of test track (though for stiff bass) and I played it numerous times for say 3-4 years;
If I play it now those rototoms appear to be roffled. Completely crazy for difference. Now, pronounce "rrrrrrrr". There's a speed in there and it will be fairly equal to everybody. At this speed (I estimate 12-15 times per second) now these hits on the rototom are performed. So each hit is actually a fast and totally clear roffle. And this was previously one hit ?? Yes it was and since it was still a rototom (very very fast/transient instrument) it seems impossible.
Envision the frequency this tom plays. This is nothing like a cymbal, there is nothing metal like a snare drum, it is just a fairly low base frequency. Only its transient implies a fairly high freqency but the base sound is low (maybe 100-200Hz). And THIS frequency is now able to on/off at a rate of 12-15 times per second while all previous OSes and XXHighEnd versions showed one hit. Can't be eh ?

I can rave about every such thing from ever track, but coincidentally this very same track of the rototoms showed me another crazy thing, most probably bound to the same improved property;
Envision lady voices to be morphed away (at fading out) into some eternity. In this case they fade out to higher and higher frequency until gone (electronic manipulation). Some chorus of say 5 seconds and the fade out is 3 seconds. This too I heard in all versions and variations quite the same. Now, yesterday I was completely shocked how this fade out turned into a sheer vocoder LOWER frequency at dying out. COMPLETELY different.
Actually this whole 19 minute track showed a sort of upside down performance from what I am used to of it; I always listen to it for 4 main recurring (stiff) bass parts and while the bass maybe plays 5 minutes in total it always takes me 19 minutes. In between the bass parts nothing much is going on, and things repeat and repeat. Well, all in between the bass parts must have been rewritten by someone, because it now was one big pile of interest. Not because new, but how sounds evolved (could evolve) like the woman voice turning into a lower frequency while previously it turned into fairly stupid (and (!) always critical (for hurting)) hiss.
Can-not-be.

Because there was no spur of leanness anymore (always critical for W8 in the first place) I thought to revisit Sgt. Pepper for another test time. Remember, Beatles which can always render unexpectedly. My first remark ? NOW you can hear what the guys are doing ! Suddenly all fitted and I say it again : of totally modern quality.
All is about that Indy instruements one of the guys got keen on (Harrison I think). But these are metallish sounds and what they did was emphasizing that into everything up to such over expressed cymbals (hi-hat upfront). Even the bass now appears no normal (violin) bass. That soo is some Indy instrument.
And otherwise you suddenly can see how Lennon sings with his own real voice, including looking up to the mic his Adams apple moving ...

I wanted to tell about many more experiences yesterday, but I forgot by now;
The detail is 10 times more as what I was used to from the last W8 setup (but say before the Silverstone card came in) and people say W8 is so detailed. Yes it might, but all is fake because it is the upper most frequencies only. And don't you think you can quote me from anywhere that I thought it was good. But somehow ... somehow ... the detail in that area is even more now but now it fits. It fits the fundamentals of it. Ah, wait ... :

I also tried Machine Head (Deep Purple). Remember, that totally muffled album. I just wondered what would have happened to that now. And so the strange thing : very good playable and actually in my memory suddenly 100% the same as I am used to it from vinyl. It also *sounds* like vinyl with all its aspects. Well, almost because CD is better. But main thing : dynamics are there now (there were not at all) and the whole picture is CONSISTENT. So, dynamics fit the colour of the higher frequencies. W8 ? all what could be squeezed out is silky highs with no underlaying dynamics anywhere with a triple blanket around your head (= ears).
So, highs are way underperforming still, but because the whole picture is consistent this is ok (for my brain). Nothing strange about it, and halfway the album you are used to it.
Don't put anything else with "on part" performance afterwards, because THEN you'll know again right away. Btw, no difference with the "Bill Evans" topic.

There's also my general perception of "what can we actually play ?". Well, with my normal W8 setup that became much limited. It improved a fair step with the Q3,4,5 = 1,1,1 setting but still many albums would sound too lean. One could say "so what" but to me it tells that something is very wrong. For example, a favorite of mine is Ott (such an "Ambient" performer). Well, was, because no matter what it became unplayable. So this is not a matter of "hey, does this sound too lean ?" ... no, it is about unplayable. This happens with this Ambient sh*t where all the frequencies and waveforms of the world are applied and when things don't work out strange things get profound. This can very easily end up in "high frequencies only" and let's remember my woman-vocoder example. From turning into high hiss going into low vocoder-morphed really really is a difference you know. So that. But of course it depends on the album and btw no Jazz would show that. You will notice, but unbearable/unplayable is another thing. Well, Ott works again. And how !

Peter

[AlainGr]

Thanks Peter, you present things in such a way that I am impatient to read your daily reports !

By the way, when you still mention the "power supply", even if all works fine since I disconnected (and isolated) the black wire, you are not talking about the 2 toroidal power supplies right ? This shows my total lack of knowledge about electronics...

Alain

[juanpmar]

Looking around at home you can always find a solution. This is useful for back pain and ... to isolate the NOS1!. These little bags have some sort of viscouse fluid inside. The effect? not worse than the the rubber balls I had before, in fact not bad at all. Sure Peter has a more sophisticated solution 

Juan

[juanpmar]

Again it could be the placebo but the sound with that viscouse pads seems fuller with a deeper bass, perhaps a bit darker but it looks to me like a more serious sound in the sense of more grown, more consistent sound. The image is very well defined. Now I´m using W8, non isolated Silverstone card and I haven´t touched the wire inside the NOS1 yet.

Regards,
Juan