USB audio cracked... finally!

[PeterSt]

9 minutes ago, manisandher said:

... create enough force to move the cone (in the way we want)?

 

No points for you Mani, and what I bolded is too intelligent (you added that later) and does not help you. Haha.

 

14 minutes ago, semente said:

Counter-EMF? 

 

Ricardo, I think you changed something too, or I have "Back EMF" too much in my mind as the phenomenon.

Anyway, 10 out of 10, and 11 out of 10 if you removed the "back" from it.

 

So yes. But now why ?

I am going to grab some coffee.

[manisandher]

7 minutes ago, PeterSt said:

No points for you Mani, and what I bolded is too intelligent (you added that later) and does not help you. Haha.

 

 

Hey, I thought it was obvious that the force I was talking about was 'electro motive'. It seems I have to spell everything out for you guys 

 

Mani

[semente]

8 minutes ago, PeterSt said:

 

No points for you Mani, and what I bolded is too intelligent (you added that later) and does not help you. Haha.

 

 

Ricardo, I think you changed something too, or I have "Back EMF" too much in my mind as the phenomenon.

Anyway, 10 out of 10, and 11 out of 10 if you removed the "back" from it.

 

So yes. But now why ?

I am going to grab some coffee.

 

Apparently it's more than just your average "handshake"...

 

[PeterSt]

6 minutes ago, semente said:

Apparently it's more than just your average "handshake"...

 

If I look at this longer, it could add additional points.

But if really so and as intended, it is beyond my IQ.

 

But I did not see an answer to my question yet ...

[manisandher]

It's all about Newton and his "F=ma". The speaker cones needs to be accelerated, so needs some force applied to it, supplied by the current from the amp (converted to EMF by the coil). The problem is that the speaker has mass, so the acceleration is finite... and often too slow to follow the music.

 

All off the top of my head, and no doubt wrong...

 

Mani.

[PeterSt]

Just now, manisandher said:

The problem is that the speaker has mass, so the acceleration is finite... and often too slow to follow the music.

 

Ah Mani, you can do better. Anyway, worth 2 points I'd say.

I am considering deducting a few from Ricardo because maybe he was guessing too much. 

 

All in the "kidding" environment of course. Now let's see :

 

Yes, the cone has mass. And from that perspective there's already current required not to let it overshoot. Thus, voltage is going down again already, but cone has mass and wants to continue. Now put a lot of counter-current and it will be stopped from overshooting.

But with EMF as the keyword, this is not much related ...

 

On a side note, and Mani knows it, my speakers are open baffle, and I seriously walk to the speaker more than once each and every day because I hear a "nature" in the bass and feel how the woofers behave (each to reach at the back of the speaker). This is how I learned how all the Operating Systems behave totally different in the bass region; the one OS lets the woofer move as you perceive the sound in the room, the next OS makes no sense, the other OS shows a deep bass but the woofer does not show a frequency while you know it is there in the other OS ... and so on.

 

So let me emphasize that I am more than quite crazy. But I think it helps audio.

[semente]

17 minutes ago, PeterSt said:

 

Ah Mani, you can do better. Anyway, worth 2 points I'd say.

I am considering deducting a few from Ricardo because maybe he was guessing too much. 

 

That's not fair. 

 

My comment wasn't even referring to loudspeakers (not with cEMF nor with the arm wrestling photo), but was instead a speculation regarding USB and audio signals.

But ultimately you are right, I am just guessing (for lack of knowledge in electronics).

 

P.S.: you are looking for "control" and the EMF "analogy" made sense...

[PeterSt]

So, electromotive force (EMF) ...

 

It is not 100% the thing in order. Think how each motor can also act as an alternator (there's one in your car unless you have a Tesla and it charges the battery).

 

The cone excurts (I think this verb does not exist ?), and likes to come back out of itself (this is a mechanical activity). This in itself creates electricity like the alternator.

 

This electricity / the current of it goes back to the amplifier and now influences the behavior of the amplifier itself.

I think we can generally call this the impedance reactance, to the sence that it is not wrong to think in these terms.

We also know that the impedance of the speaker changes per frequency. So per other frequency, the amplifier is behaving differently because it receives back current from the speaker and the amplifier must fight against it.

The more current, the better it can fight the "back current" (I made up that term). The more current, the more stable the behavior of the whole chain.

The less current, the more a mess the whole chain becomes, because the speaker itself is going to determine more what the amplifier sends "the next round" (the speaker could imply more current back than the amplifier ever sent, which is all related to build up of the wave (when slow the amp can do it) and how sudden it stops (when fast, the driver bursts a lot of current to the amp).

 

 

 

[manisandher]

But isn't that exactly what R meant by 'back-' or 'counter-' EMF?

 

Mani.

[manisandher]

Thinking about USB...

 

So is it generally about 'compliance'? The Clarixa is low compliance and the Lush high compliance?

 

Mani.

[PeterSt]

When no mechanical activity is in order, there is still a reactance from the other side. All electrical connections have. Thus, the other side reacts, it reacts differently per different frequency and the poor sender has to cope with it all consistently. And oh, what I did not tell yet, is the more current is used, the more reactance is implied from the other side. Just think about the speaker driver's excursion again, and how it coming back from 1" implies more current than it coming back from 1/2".

It starts to be rather complex now.

 

It is clear that with our USB interface we can not reach the transmitter (or transceiver if you like, anyway at the PC's end). It does what it does.

The same counts for the receiver (in the DAC).

Right ?

 

Well, maybe we can after all. See the loudspeaker story. If I change the driver (say to a more efficient one), I will influence the transmitter (amplifier). So hey, I can influence the transmitter !

But wait, if I can influence the transmitter, and it would be for the better, I will influence the receiver just the same.

Or ?

Yes. If the transmitter requires less current to control the receiver, then the receiver itself behaves better.

(watch for the chicken and eggs)

If the receiver behaves better because it wasn't fed so much current in the first place, its reactance variance becomes less.

 

And now notice that here all analogy with the loudspeaker stops, because this is digital and we don't need high or low volume (voltage = current). It only needs to work (pass some thresholds to turn a 0 into a 1 and 1 to 0).

So, we can make the voltage and current implications as low (or as high) as we like, as long as the protocol keeps on working, which means that no bits are allowed to "flip" (be different in the receiver compared to how they were sent by the transmitter). And yes, the lower the voltage the more jitter because of noise (SNR becomes worse), but coincidentally I don't care a hoot in this cable.

 

Well, that was it.

And although I imply a very low voltage, I am not saying that it is working (out) like this.

Not a all. You just don't know. So I only tried to explain how the behavior of the lot can easily change, with the objective of influencing the receiver and beyond, because it is *there* where the sound will change for again various reasons (one of them being jitter and I say it again - in that domain; and how that turns into jitter (or not) requires a book).

 

For the mere unbelievers, please keep in mind that I already do this with software alone. So wouldn't it be more easy for me to do similar with a USB cable ?

Fact is, 3 months ago I did not even think of it.

And tomorrow another day.

[PeterSt]

18 minutes ago, manisandher said:

But isn't that exactly what R meant by 'back-' or 'counter-' EMF?

 

 

What you will have read by now, yes. But the difference is in the quotes. So both are phenomena which exist - they are the same : https://en.wikipedia.org/wiki/Counter-electromotive_force - but if you read into that fairly small page, you see it is about something different really (in my younger days it was a means to control model railroad trains in a better fashion - read that Wiki page and you will see it). But :

 

You now have 8 additional points because it is about countering it. So the quotes make the difference, also for the back, which in my book is about the backfiring of it.

This is all not rocket science for those working with it, but we must recognize that he effects of it are everywhere, as long as we think in terms of reactance which is just disturbance.

 

Maybe I am still full with having piles of speakers in the car when I was 20 and beyond (pick your direction) and that all was heavily distorted when set to loud and I was sure that the speakers were too small. But the salesman in the shop managed to sell me an even larger amplifier (like 1000W instead of 200W) and the problem was solved indeed. Maybe that day I learned the most for my future audio, knowing that I just left electronics highschool because computers just emerged and I went that direction.

It is totally crucial in everything and that's why the example.

[PeterSt]

29 minutes ago, manisandher said:

Thinking about USB...

 

So is it generally about 'compliance'? The Clarixa is low compliance and the Lush high compliance?

 

If you add "for Audio" to it, yes. Because that is what I explicitly did. And I can tell you that this implies some environmental challenges ...

Clairixa should be highly compliant to USB2. But who needs that ? 

[manisandher]

16 minutes ago, PeterSt said:

Clairixa should be highly compliant to USB2. But who needs that ? 

 

No, I didn't mean compliant to the USB spec. I meant in the mechanical sense. If the Lush is higher compliance, it helps me understand the following better:

 

30 minutes ago, PeterSt said:

If the receiver behaves better because it wasn't fed so much current in the first place, its reactance variance becomes less.

 

A bit like... if I wanted a smooth ride over a bumpy road, I'd prefer a car with highly compliant suspension - the ride height would have less variance.

 

Mani.

[PeterSt]

10 minutes ago, manisandher said:

A bit like... if I wanted a smooth ride over a bumpy road, I'd prefer a car with highly compliant suspension - the ride height would have less variance.

 

Ah, OK. No, that is now how I operate(d). I could say Yes because it will come across nicely, but No.

It reminds me about this though, which was foremost in my head when I started the posting sequence :

 

*Because* all what's USB2 spec should have been made to that spec really (with no guarantee, but still), all behaves in a certain electrical fashion and it is as is. This also counts for your USB interface in the DAC and it also counts for my USB interface in the DAC. Again, nobody anywhere made that for audio, and its behavior will be, say, too noisy because of it. "Too" means : unnecessary. This can all be counter attacked with some more careful thinking, and I don't mean : throw femto clocks at it (which btw I do too but for very different reasons).

 

Guys, it is all so easy if you only stick out your electrical sensors and have a slight degree of ignorance;

With a wink to Alex C. ...what was it all about this Silanna chip you say ? Well, the g-d f* chip never was made for audio (btw, Intona the same). It plainly does not work !!!

(yes, I am getting shouty because of it)

So of course the chip maker does his best, but he failed because the USB2 spec is not an audio spec. And he forgot to look at the errors which can not be corrected in audio.

 

We audiophools abuse USB in-depth. And in aftermath we try to correct it for audio.

Have a nice day.  

 

[semente]

I suspect that you are applying dynamic compression to the signal, @PeterSt

 

That's not a nice thing to do. 

[PeterSt]

Just now, semente said:

I suspect that you are applying dynamic compression to the signal, @PeterSt

 

With me and my tunnel vision ?

 

Oh boy, writing this, I suddenly see another means of electrical tweak.

But I already had another one, so this is for 2020. 

[elcorso]

19 hours ago, Doak said:

Today's obervation(s):

The gap between PCM and DSD has been all but closed. My DAC (see signature) has dedicated "engines" for each, and I've had a distinct preference for it's DSD playback.  What I'd noticed most with PCM was a some graininess at the edges of notes along with a slight hollowness. Listening through my PCM reference playlist today I do not detect a bit of either of those undesirable qualities. 

Words of the Day: REFINED & MEATY

 

Bold is mine.

 

Well 'almost', but please remember @PeterSt is a PCM man 

 

Anyway, the Lush is closer to analogue, but with the huge advantages of digital on frequency extremes, like I mentioned in my previous posts.

 

But I have to be honest, since HQPlayer is what I use and all my music files are (were) converted to DSD I have no experience settings the filters for PCM on this music player.

 

REFINED & MEATY? Fully agree.  Like rice & beans cooked on coconut oil (a traditional dish on the Caribbean side of my Rainforest).  Or Roch's paella, spicy enough but you will not miss the palate to taste the seafood

 

Roch

 

PS/ This weekend the maid had his days off and I don't have any of my RF previous problems!

It's true that she carries 3 cel. phones that connect to my WiFi.  What kind of app she could have that causes such interference?  Sorry to derail the thread but no one pm'd me...

 

[cmarin]

11 hours ago, manisandher said:

 

Listening impressions of the Lush from numerous people from around the world, with totally different systems, suggests the Lush's 'working as advertised'. (I won't list them all again - most are here in this thread.)

 

Mani.

 

FWIW, as Peter pointed out, my NOS1a was not in my possession when Peter's Lush USB cable was delivered.  

 

The improvements that I experienced with Peter's USB cable occurred with two different DACs: Pacific Microsonics Model 2 and the Aries Cerat Kassandra Reference Mk2. Both are amazing DACs. And if that's expectation bias, then so be it. But my enjoyment of my system with Peter's cable is still real and getting better as the cable settles. And the improvement, to an already good system, was not subtle. Of course, YMMV.

[manisandher]

29 minutes ago, cmarin said:

The improvements that I experienced with Peter's USB cable occurred with two different DACs: Pacific Microsonics Model 2 and the Aries Cerat Kassandra Reference Mk2. Both are amazing DACs.

 

You have some great DACs! (I had the pleasure of listening to the AC in Munich earlier this year - one of my favourite rooms. And it goes without saying that I'm a massive fan of the PM2.)

 

29 minutes ago, cmarin said:

And if that's expectation bias, then so be it.

 

All my ultra-expensive analogue and digital cables are sitting in my basement gathering dust. They simply don't sound as good as the much cheaper stuff I'm using. And I prefer the sound of the $500 gainclone amp I'm currently trying in my office system over the bunch of >$10k amps I own. Strange thing this 'expectation bias'...

 

Mani.

[matthias]

1 hour ago, manisandher said:

And I prefer the sound of the $500 gainclone amp I'm currently trying in my office system over the bunch of >$10k amps I own. 

 

Mani,

interesting,

which one is it?

Thanks

 

Matt

[Jud]

10 hours ago, PeterSt said:

So, electromotive force (EMF) ...

 

It is not 100% the thing in order. Think how each motor can also act as an alternator (there's one in your car unless you have a Tesla and it charges the battery).

 

The cone excurts (I think this verb does not exist ?), and likes to come back out of itself (this is a mechanical activity). This in itself creates electricity like the alternator.

 

This electricity / the current of it goes back to the amplifier and now influences the behavior of the amplifier itself.

I think we can generally call this the impedance reactance, to the sence that it is not wrong to think in these terms.

We also know that the impedance of the speaker changes per frequency. So per other frequency, the amplifier is behaving differently because it receives back current from the speaker and the amplifier must fight against it.

The more current, the better it can fight the "back current" (I made up that term). The more current, the more stable the behavior of the whole chain.

The less current, the more a mess the whole chain becomes, because the speaker itself is going to determine more what the amplifier sends "the next round" (the speaker could imply more current back than the amplifier ever sent, which is all related to build up of the wave (when slow the amp can do it) and how sudden it stops (when fast, the driver bursts a lot of current to the amp).

 

 

 

 

Hi Peter.  Don't know if anyone got back to you on this, but the English for what the speaker cone or diaphragm does is "excurses."

 

One amplifier spec relevant to the amp's resistance to the inertia of the speaker cone or diaphragm is damping factor.

[Jud]

3 hours ago, elcorso said:

Or Roch's paella, spicy enough but you will not miss the palate to taste the seafood

 

OT: Mmm, paella!

[Ralf11]

13 hours ago, Speed Racer said:

 

Why don't you explain specifically what your cable is doing to affect the sound coming out of the analog side of the DAC? 

 

 

it is possible that he doesn't know

 

or it could be a trade secret

[rando]

8 minutes ago, Ralf11 said:

 

 

it is possible that he doesn't know

 

or it could be a trade secret

 

1.  Hope it takes exactly the wattage in my smile to gain access to MQA source code.

2.  Send formal request to PeterSt noting I've yet to receive the technical filings he has on record for "Lush" USB cable.