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An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter

85.19.92.6
Posted on December 10, 2014 at 00:12:52
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
 Hi
is this true ? that if a usb dac is really well designed its performances should be quite independent from the pc used ?
As long as the pc is at least decent i mean ... that for me it means able to run nicely a 64 bit OS.
I tend to think so but i would like to hear from people with usb dacs above any suspect
I have an humble candidate for a good and cheap usb dac ... the Cambridge Audio Dacmagic
I have the strong feeling that with just a better power supply can sound quite good indeed
For instance it can work also without USB power from the pc. Nice.
Maybe it is not the end of the game but i tried it quite extensively with very different pcs and the sound was quite identical.
Thanks a lot for any kind advice.
Kind regards,
bg

 

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RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 00:32:43
John Elison
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Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 I agree that the largest differences will be heard from different DACs. That is my experience, but I've used only two different computers and four different DACs. I heard no differences from the computers but significant difference among the DACs.

Good luck,
John Elison

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 00:46:21
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks a lot for the very valuable confirmation
Now i understand that i should really put more resources in the usb dac
Thanks again


Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 03:08:10
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

> is this true ? that if a usb dac is really well designed its
> performances should be quite independent from the pc used ?

Depends on how you define "performance". You must account for the system.

Unless the PC is fully isolated from the DAC (requires USB isolation, real one) your systems performance is likely to be influenced to some degree by how the PC manages RFI, noise etc.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 04:01:21
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
 Hi and thanks for the reply
What i meant is that if the usb dac is designed and built correctly and therefore provides, among other things, full isolation from the PC, changing the pc source upstream, with any other thing unchanged from the usb dac down, should not affect the final sound significantly.
Maybe only an extremely resolving system could highlight small but not very significant changes in the sound.
I think tha this could in some way tame all the debate about pc quality and so on and we could put more energy and resources on the rest of the chain from the usb dac down to the speakers
Just a decent pc able to run a 64 bit OS should be enough.
I have understood by the way that the usb interface is a very critical point and not that easy to execute rightly.
Of course i would be very happy to hear the opinions from someone who has tried in a high quality system with a very high quality usb dac to swap the pc source
Thanks again.

P.S. i am sorry for the very bad English but after having founded Londinium in 50 A.D. we have in some way lost the control of the situation


Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 04:37:07
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

> What i meant is that if the usb dac is designed and built correctly
> and therefore provides, among other things, full isolation from the
> PC,

Good luck finding one.

Common digital isolators in the Digital Audio section can easily add several nanoseconds of jitter, so they are rare.

Readily available USB Isolator systems remain resolutely stuck at 12MBps, which limits them to 96kHz 2-channel audio (good enough for CD standard Audio but little else).

Another option is to isolate the ULPI Bus if available, this means bidirectional isolation for 8 Bits, Clock, direction and other housekeeping at > 60MBps, also no cakewalk.

So isolated USB is usually rare. As another thread showed, even some gear that should be isolated reads 0 Ohm between USB ground andAudio Ground (read no isolation whatsoever).

> changing the pc source upstream, with any other thing unchanged
> from the usb dac down, should not affect the final sound
> significantly.

Lot's of if's and butt's (more than in a Vegas Strip Joint) here.

Like you must also keep noise from the PC out of the mains, unless your gear is designed to block such noise.

But yes, IN PRINCIPLE, if money was no object, if any agency requirements could be safely met or ignored if they cannot be met and if all parts of the audio systems were designed for sufficient EMI/RFI etc. Resistance, then yes, your contention should hold true.

Just remember that in theory there is no difference between theory and practice...

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 05:49:17
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thank sincerely for the kind explanation unfortunately way beyond my knowledge
You say " isolated USB is usually rare " i say ... why ?
Is it really that difficult ? is it really that expensive ?
Just asking
When i read of people who use usb power supply and say that there is a big improvement i wonder who has designed the usb dac ... he knows what he is doing or what ? That should not happen at all.
If you see my point.
Thanks again.
Kind regards,
bg

 

I think that *might* be true, posted on December 10, 2014 at 08:04:39
Beetlemania
Audiophile

Posts: 1217
Location: Utah
Joined: November 1, 2003
 I have the Ayre QB-9 DSD which is galvanically isolated (whatever that means!) and produces its own USB power independent of the computer. The computer-side tweaks I've tried have made little to no difference in SQ.

From Computer Audiophile: "Connected to most DACs I can easily hear all kinds of garbage as if five refrigerators were sharing the same power outlet with my audio system. However, when I connect this electrically noisy computer to the QB-9 DSD I hear silence through the speakers. "

But I've read reports from at least one other QB-9 owner that claimed the QB-9 is sensitive to computer-side tweaks. Go figure.

 

Define "well built", posted on December 10, 2014 at 08:54:22
Presto
Audiophile

Posts: 5957
Location: Canada
Joined: November 10, 2004
 Does build quality speak to motherboard layout, quality of components, power supply quality, etc., or does it include firmware? Codecs? OS? OS Config?

I'd rather have a Dell or HP computer that is set up carefully and streamlined for audio use than some "high quality" machine that is used as the family PC inundated with every OS component, startup components, Java, sofware updaters, bloatware, adware, helpware, or a machine where the event viewer is not even checked for errors.

Forget that. I want the "quality" machine AND a quality installation of OS and software. And by quality, I first and foremost mean MINIMIZED!! :)

Cheers,
Presto

 

RE: I think that *might* be true, posted on December 10, 2014 at 09:20:02
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks a lot for the interesting reply
On principle i tend to believe the opinion of professionals more than those of amateurs especially professionals in the specific aerea.
IMHE usually they are right. If they say that is wonderful is very very good indeed.
So the CA review of the Ayre seems to point in that direction and that at Ayre they have done a very good job.
As a minimum when a usb dac sounds better with a usb power supply means that it has a weakness in that specific aerea.
Thanks again.

Kind regards,
bg

 

RE: Define "well built", posted on December 10, 2014 at 09:36:32
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and sorry but i do not have the answer.
But yes of course drivers are also important.
My main aim is to make the pc issue the least influencing.
And also to avoid a very complex front end with boxes, filters and seismic bases and so on. Something basic but good.
Pc + usb dac and stop.
And i have to say that for instance with the Cambridge Audio Dacmagic the result was quite similar with different pcs.
I found it a little flat and dry for my taste but non bad at all.
I have decided to try another usb to spdif converter with a dac i have already
Next time i will try a usb dac and listen for the best sound.
Thanks again.

Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 12:05:24
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

> You say " isolated USB is usually rare " i say ... why ?

Because it represents drastic engineering challenges that so far have not been overcome in a manner and fashion that easy to implement, never mind cost.

> Is it really that difficult ?

If someone brings out a suitable Isolator Chip that works at High Speed USB2 rates (480MBPS), no, until then it is trivial if all you need is 12MBPS, or should be. If using 12MBPS the maximum standard sample rate supported is 96kHz - 2-Channel.

> When i read of people who use usb power supply and say that
> there is a big improvement i wonder who has designed the usb
> dac ... he knows what he is doing or what ?

Probably yes, he does know what he does.

> That should not happen at all.
> If you see my point.

I do not. Particularly.

If you are willing to spend unlimited amounts of money you can of course demand the kind of things you suggest. In a cost limited application, it is a different story.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 12:24:27
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 I agree with you that this is how things should be. However, they are not this way because of the direction the market has taken.

I blame the reviewers for this sad situation. They review DACs using fancy digital front ends. If a DAC sounds good under those circumstances they give it a good review. However, they shouldn't do this. If they used the cheapest computers to review DACs and panned any DACs that didn't sound good under those circumstances the manufacturers would be forced to provide a suitable level of isolation.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

If you really want to open up a can of worms in this very forum....., posted on December 10, 2014 at 13:46:43
AbeCollins
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Posts: 46280
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
 ...try asking this question:

With the assumption that the computer is somewhat new within a few years, 100% functional with no issues, and not a broken down sluggish virus infected clunker ready for Goodwill......

- Which makes the most noticeable difference in sound, trying various computer tweaks including different operating systems, linear vs switching power supply, no fan vs fan, shielded SATA cables or not, operating system 'slimming', etc. -OR- the various choices in Async USB DACs on the market? So which makes the biggest difference?

Unfortunately, my answer ruffles the feathers and upsets the small but vocal tweak of the week culture that lives in this forum. Nothing wrong with tweaking for improvements but the gains are small vs hearing the differences among several of the different DACs on the market.

It has been my experience that any given decent Async USB DAC pretty much retains it's characteristic sonic traits whether it's attached to a stock Dell running Windows XP, a Levono running Windows 7, or a Mac running OS X Mountain Lion, etc. Move that DAC to a variety of computers and it will sound pretty much the same regardless. Take another DAC that sounds different than the first one, and move it to various computers and it too retains it's sonic character. They don't magically change like chameleons and take on the 'character' of the computer.

Take this a step further and tweak a computer to death vs running it 'stock'. The DAC itself will still have the bigger influence over the system sound (keeping the other downstream components constant of course). A tweak here and there might improve things slightly but the change is not going to be as big as trying a totally different DAC.

A rolled off, veiled, and dynamically challenged DAC on computer A doesn't become dynamic, transparent, and extended on computer B.




 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 14:00:04
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 Don't even consider isolating the USB signal. Were you to do so, the packet processing overhead on the DAC side of the isolator would still nail you as John Swensen discovered. Treat the entire USB section as "dirty". Do the isolation at much lower data rates, e.g. I2S rates. Send the clock from the DAC through its isolator to the USB converter section, synchronize it with the packet buffer, and send back the audio data in the DAC clock domain through a separate isolator. You can easily reclock (flip flop or shift register) in the DAC clock domain. Repeat the isolate and buffer mantra as necessary...

A single stage flip-flop will eliminate some noise (phase noise and amplitude noise) but not all because signals will leak around open switches and closed switches because the flip flops aren't completely "hard". However, multiple stages can be ganged in a shift register given appropriate clock phasing to get more isolation. The limit will be power rail noise shared by the stages of the shift register. Hence, the possible need to use a second stage of isolator, and reclocking to remove its noise.

Note that multiple stages will not produce a perfectly clean digital signal. There will still be noise. However, multiple stages of isolation will provide as much decorrelation as desired from the original signal. The problem of getting good analog to digital conversion will remain. :-)


Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

+1 ...........And Well Said!...............................nt, posted on December 10, 2014 at 14:33:33
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 nt



 

GASP!, posted on December 10, 2014 at 15:49:58
Presto
Audiophile

Posts: 5957
Location: Canada
Joined: November 10, 2004
 Emperor has no clothes!

Run!

Cheers,
Presto

 

+ n, posted on December 10, 2014 at 16:20:22
JeffH
Audiophile

Posts: 4574
Location: Orange County, So Cal
Joined: April 5, 2000
 N equaling whatever number we're up to.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 17:53:32
Scrith
Audiophile

Posts: 1169
Location: Los Angeles
Joined: July 19, 2005
 I agree. The DAC should be designed so that it sounds the same regardless of the source of the data it is using (assuming the source can at least provide the data at the required rate).

This leaves two jobs for the DAC (as far as receiving the data):
1. It should be able to overcome any timing problems with the incoming data (i.e. it has no dependency on the speed at which the data is being transmitted)...otherwise known as buffering.
2. It should be reasonably well isolated from the notoriously noisy USB connection.

With such a DAC, the computer, the software, and the storage device(s) (and connections to them) should be irrelevant. On the other hand, if you are using a DAC that seems to sound better depending on what software you use, or which brand of computer, or storage device, or USB cable...you've got a bad DAC.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 18:21:45
Sprezza Tura
Audiophile

Posts: 4585
Location: New York City
Joined: August 24, 2012
 Uh no. Your notion is rather absurd.

Let's examine what you say...if we extrapolate reviewers should use garbage home theater amplifiers to review SOTA speakers.

I blame reviewers for parroting absurd claims by manufacturers and spreading lame buzzwords, but NOT for using high quality front ends.

Your statement holds no water.

MANUFACTURERS are the ones who should design and test their DACS with piece of shit front ends. Not reviewers.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 19:05:21
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 The effect of the PC depends on a lot of different factors. Using USB makes it more difficult to get computer independence. The best way I believe is to use network renderer. This way the data is packetized, the system is galvaically isolated and most important, the audio stack can be mostly avoided.

 

RE: "MANUFACTURERS are the ones who should design and test their DACS with piece of shit front ends.", posted on December 10, 2014 at 20:06:59
Ivan303
Audiophile

Posts: 48887
Location: Cadiere d'azur FRANCE - Santa Fe, NM
Joined: February 26, 2001
 If they SHOULD but likely many or most do not, then I would think that's all the more reason reviewers should.




First they came for the dumb-asses
And I did not speak out
Because I was not a dumb-ass

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 23:11:13
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thank you very much again for your very kind and helpful reply.
Even of course the all stuff is quite beyond my ability to understand i have realized that, as often i do, i was very trivializing the issue
I thought was a much easier task but clearly it is not.
No more ramblings on the subject. Promised.
Thanks a lot again.


Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 10, 2014 at 23:21:55
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks a lot for the very interesting advice
First i have to say that i am not in the position to judge seriously the quality of a digital sourse having a very low level set-up
I can also say that lately the average quality of the digital source seems to me quite good. I like even the sound coming from a Panasonic BR player. So my system is hardly high rez (and maybe also my ears).
But i am in the process to try a usb to spdif converter and try it with different digital PC sources (laptop Apple and Windows, desktops) just to hear for differences.
And i like the idea to be able to use the pc with this interface and a nice vintage dac.
But i have understood that while the asyncronous usb transmission has a very interesting potential is not easy to do it rightly.
Thanks again




Kind regards,
bg

 

RE: If you really want to open up a can of worms in this very forum....., posted on December 10, 2014 at 23:29:22
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thank you very much indeed
Your advice is very valuable to me
I am still undecided between a usb to spdif interface + vintage dac or a new usb dac
I read good things about old high quality dacs' sound that intrigued me.
Thanks a lot again. Message received.
Kind regards,
bg

 

" ... network renderer ... ", posted on December 10, 2014 at 23:31:16
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks a lot for the kind reply
May i ask what is a " network renderer " ?
I do not have a clue ... but i am curious of course.
Thanks again.
Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 00:12:12
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

To give you a "datapoint", you can but commercial USB Extenders that send USB over optical fibre and handle 480MBPS (High Speed) and of course also isolate the signal.

All the ones available I have seen so far cost around 1,000 Euro Retail and there are not many options out there.

The Owen Corning Optical USB Cable starts around 300 USD per piece (likely 300 Euro if sold in Europe) and if employed correctly also isolates a single, self powered peripheral (e.g. DAC).

So if you are willing to pay that much you may isolate your DAC from the Computer without penalty (other than financial). I am waiting for one of the Owen Corning cables (they seem in short supply) to try.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 00:18:01
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Tony,

There are many options to isolate things.

One of the problems is that the common RF based isolators often cause more RFI than they remove. And if you need 50MHz bit-clock few isolators will even work acceptably.

All options have substantial challenges to resolve and are not cheap.

I tried something using in principle Ethernet targeted parts (magnetics and LVDS drivers), but even this in the end is neither cheap nor that good.

If you have any suggestion of a simple and reliable low jitter solution that does not create massive amounts of RFI of it's own, I am looking, a PM will be fine though I would not mind if you can share it in public.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 03:00:57
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks again for the very interesting advice
I guess that in a very high rez/quality system this devices can really make a difference
As a start i will listen for any noise or audible click/pop and distortion
Personally i think that digital recordings with a soundstage particularly well captured are a very good tool to assess the quality of a playback system.
If the system images very well is a " really damn good system " as Mr. Doug Sax used to say. And i agree of course.
Thanks a lot again.
Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 07:26:42
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 Your analogy is bogus. A digital source is not in the analog signal path of the playback chain, unlike an amplifier.

It should be the responsibility of the manufacturers, editors, and reviewers to educate non-technical consumers. Unfortunately 30 years after the introduction of digital audio most of these people remain ignorant of the technology, or if knowledgeable are locked by business connections to a marketplace that amounts to Veblen goods for rich assholes, not tools for musicians and music lovers.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 07:52:16
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 No, I have no magic solution, just using multiple stages of isolation. I think the bulk can be done with optical isolators. I suspect pulse transformers will work as well, depending on the signal coding due to the problem of passing DC. The last stages of buffering will require hard flip flops and very very careful power and ground distribution.

The first problem is to characterize the situation, i.e. to see what people are hearing and how sensitive they are. Then the second part of the problem is to figure out how to measure this reliably, including measuring isolation from the source.

If I were you, I would look for people who design high speed crypto equipment (red black separation). They probably have this problem pretty well nailed, since their goal includes preventing any information from leaking other than the intended bits.



Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

Ahhh.... it's the "Perfect DAC" (TM) rears its beautiful head again., posted on December 11, 2014 at 09:09:07
carcass93
Audiophile

Posts: 7181
Location: NJ
Joined: September 20, 2006
 It was discussed so many times before that it's not even funny anymore, but just a thought:

Is it possible that reviewers, based on their experience, realize that there's no DAC in existence that would make crappy transport sound good? And, accordingly, they try to achieve the best sound possible, using the BEST transport available to them - just as regular audiophile would do?

I wouldn't mind seeing a paragraph in a review, devoted to evaluation of performance of DAC with the worst source possible, just to see how well it rejects the egregious nasties fed to it. Elsewhere on this page, Beetlemania quoted CA review of Ayre DAC, something along the lines of "5 refrigerators..." - which is great, but even then, Chris C. doesn't pursue evaluating actual sound quality in that setup.

Anything beyond one paragraph would be just feeding the irrational side of the reviewer - and of the readers alike.

 

a brand new term, designed to confuse everyone, posted on December 11, 2014 at 10:26:04
Sordidman
Audiophile

Posts: 13665
Location: San Francisco
Joined: May 14, 2001
 We can have conversations with all new, different, and undefined terms, so no one knows what we're talking about.

Our Squeezebox touchs are "network rendering, streamers, music servers, mini computers"

Or we can call them NRSMSMCs for those wishing to proceed further down the path of obfuscation and pedantry.

NETWORK RENDERING traditionally is VIDEO. Typically, it means to "fill in" or "render in" skins over 3 dimensional vertices, (covering them). Rendering these complicated 3D wire frames would often take many hours and A network rendering program would utilize the processing power of many individual PCs, and servers, in a network to "cover" these wire frames.

Likely, in this case, - he probably means something like the Aries, SoTM, Bryston, Sim Audio Mind, - etc.

Cheers,


"Asylums with doors open wide,
Where people had paid to see inside,
For entertainment they watch his body twist
Behind his eyes he says, 'I still exist.'"

 

RE: Define "well built", posted on December 11, 2014 at 10:26:50
Presto
Audiophile

Posts: 5957
Location: Canada
Joined: November 10, 2004
 BG:

I am not really sure which of the very long list of tweaks and "optimizations" are really necessary, but I think it IS good to get rid of the glaring errors and problems in the OS and software. Minimizing services and start-up programs is important, as is preventing a lot of software from "auto updating" and interrupting a listening session.

It would not be hard to A/B compare two different computers with a USB DAC at all.

At the end of the day, it's the listening that matters. Our ears and our perception of sound is all that matters. Some even admit to being okay with placebo effect, if the effect is a positive one! That used to drive me crazy, but now I get it. The placebo, much like the tweak that actually "does something" is, like all other tweaks, a means to an end: better PERCEIVED sound!

So even if a tweak has only placebo effect, in my mind it has value if it (a) gives the user some enjoyment in the tweaking process and (b) actually results in him perceiving better sound! ;)

Cheers,
Presto

 

RE: Define "well built", posted on December 11, 2014 at 11:42:48
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Thanks a lot again for the valuable reply
but i am somewhat disappointed by the usb technology
The USB with its asynchronous digital transmission carried the promise of no jitter issues, passing the task to the dac
I understand that the pc could be an issue if the usb interface is less than optimal. This is fine.
Now i have also understood that to design and build a very good usb interface is not that easy task i thought at all.
Let's hope that better chip and better design will be available
Thanks again.

Kind regards,
bg

 

"network rendering, streamers, music servers, mini computers", posted on December 11, 2014 at 14:14:07
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 I believe there are different protocols involved. The bits sent over the Ethernet are not the same. Protocols designed for use over a local area network on dedicated links can be considerably simpler and more efficient than those that must run over arbitrary networks including the Internet. This impacts the processing that is located close to the DAC and hence, potentially the sound. Unfortunately, in both cases, as with USB, there is still a lot of processing, something that requires a considerable amount of computing power and the likely noise.

Most product terminology is created for marketing purposes. A classic example is "Direct Stream Digital" which is nothing but 2822.4/1 PCM rather than 44.1/16 PCM. Of course when one looks at the format this way one immediately sees DSD has high sampling rate (good) and DSD has low bit depth (bad) and hence one expects there to be tradeoffs, as in fact there are. This is all about creating market niches, publicity and in some cases cults.


Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

In audio or in traditional network rendering?, posted on December 11, 2014 at 15:11:07
Sordidman
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 These are TCP/IP connections with the typical, (physical, transport, internet, data-link, & application layers). When rendering 3D video object vertices, - it's all TCP/IP.

With digital music playback transports, - it also uses TCP/IP to either grab the file and load it into memory, - or play it, (stream), it from the box.

These are not marketing terms: they are old computer terms to describe the packet transport performed by the TCP/IP protocol: correct?

The terms created to describe the events are not of a concern, it's a question of how we define things, so that we all understand what we're talking about. The term "DSD" no matter who created it, is fine until the point where it gets confused with other terms, or it's used erroneously. If we start with DSD discs, SACDs, it was clear that DSD was something entirely different than redbook, (also not the most creative term).

The point of my post was that we should come to some sort of consensus about some of these definitions, or we're going to be spitting into the wind in two different languages, blathering lunacy.

The OP asked what was meant by "Network Renderer" we still don't know.



"Asylums with doors open wide,
Where people had paid to see inside,
For entertainment they watch his body twist
Behind his eyes he says, 'I still exist.'"

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 11, 2014 at 15:16:23
Sprezza Tura
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Posts: 4585
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 Tony, you claim Ethernet require a considerable amount of computing power and processing. Really now?

A network player, streamer, whatever you want to call it, the size of a pack of cards will have absolutely no trouble streaming a 24/192 WAV, FLAC, or AIFF file. None. That is because it is designed to do nothing else.

I think we continue to chase phantom problems in computer audio.

 

RE: In audio or in traditional network rendering?, posted on December 11, 2014 at 19:30:53
Tony Lauck
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Posts: 13629
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 I may be mistaken, but I don't believe that the new standards for studio audio use TCP. Audio is transferred in hard real-time with absolutely minimal buffering as would be required for sound on sound studio use. (I haven't studied the protocols as the standards are beyhind a paywall.)

One thing is pretty clear, and that is that the Squeezebox protocol is source independent. Once you buffer ahead sufficiently, you can pull the plug and power down the source, playing out of memory on the Squeezebox. At this point there will be little scope for the source to affect the sound quality. (Or maybe not, but if you go there then it is only a small step to worrying about the Ethernet cable at the HDtracks sever to the HDtracks router. Personally, I worry more about the record label shysters marshaling the files that get uploaded to the server.)

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 11, 2014 at 19:40:53
Tony Lauck
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 You have to look at peak processing, not average processing. If you transfer the samples one at a time to the DAC then it processes them one at a time. The processing cycles at the sample rate. If you transfer samples a buffer at a time, then the processing takes place each time a buffer arrives. This results in a busy period followed by an idle period at the buffer rate. Given typical packet sizes the cycle time will be in the middle of the audio range, e.g. 1 kHz for USB. The numbers will be similar for Ethernet. Noise associated with this processing may be audible. This is similar to the situation that many people have observed in computer audio where reducing the buffer size improves the sound quality up to the point where buffer overruns start happening and audible glitches appear.

These are real problems. There is a lot of debate about why these effects happen and what the best (or most economical) way of dealing with them might be. However, careful listeners all notice that bits are not bits, or at least usually do not appear to be such. There is spirited debate as to what to do about it. Of course there are people who deny this can happen, but you will find them on other forums.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: In audio or in traditional network rendering?, posted on December 11, 2014 at 19:43:25
Sprezza Tura
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 the same applies to all the streamers I have in my systems. I can shut down my server software and my computer with my library attached and I can get sometimes two more songs to play.

Yes, isolation of source and DAC. You are starting to get it.

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 11, 2014 at 19:47:18
Sprezza Tura
Audiophile

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 I understand what you are saying.

However, explain what kind of noise can affect playback when the computer/NAS never directly interface, and only communicate via a router, and 30 feet of shielded CAT7 cable

 

RE: In audio or in traditional network rendering?, posted on December 11, 2014 at 19:55:37
Tony Lauck
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Posts: 13629
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 Best way to isolate the source and the "DAC" is to stream the entire playlist at gigabit speeds to the "DAC", power down the source and the network connection and listen to the music out of memory in the "DAC". This was done a decade ago for CDs with the "Memory Player".

This won't work for some applications, such as streaming from the Internet or studio processes such as sound on sound or editing, but this will eliminate the "source" from the equation. If you are impatient then you had best not do any DSP in the computer or if you do so you had best have a very fast multi-core processor, or you can do your preprocessing off-line and store the results on disk if you have stock in Seagate, Western Digital or Hitachi.


Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 11, 2014 at 20:03:27
Tony Lauck
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 What you will hear isn't the computer noise, just the packet processing noise. The timing of packet arrivals will depend on what goes on in the computer. Hence the timing of the packet processing noise depends on the computer. John Swensen has posted about observing this effect. Note: if you change the timing of the noise then the effect on the music will change, hence the listener may perceive differences. To hear consistent sound one will either have to reduce the noise to insignificant levels or time the noise so that it is consistently correlated with the music, or alternatively reduce the quality of the playback by various means such as adding much louder masking noise. This might hide any source differences, but this would not amount to a good outcome.




Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 11, 2014 at 20:28:30
Thorsten
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 Tony,

Common optical isolator are way too slow for the sample rates I run my stuff at.

Pulse transformers that are off the shelf suffer bandwidth limitations that are not easy to overcome.

The bit at the end is not so difficult... I had that for ages in most of my DAC's.



Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

what is a " network renderer ", posted on December 11, 2014 at 21:32:46
Thorsten
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 Hi,

A "Network Render" is a custom build Computer aimed at playing audio (or Audio/Video) via network connections. A prime example is the Popcornhour range.

It is build from the same commodity hardware parts as general purpose computers and uses fundamentally the same kinds of designs and design techniques, but omits functions/memory/processing power not required for the audio or AV role and it may (or may not) provide improved circuitry for the audio or AV functions.

Operating systems are generally modified/optimised/stripped down general purpose OS (Linux and Windows embedded are most often found).

In many cases the commodity type network renders are less expensive than general purpose computers purchased new at full retail (though more than you pay for a "leftover laptop" which is free).

Some are marketed squarely at the high end audio market and command large premiums. The degree of customisation for these devices ranges from fully custom build designs to generic PC or phone/tablet hardware bodged into fancy boxes with expensive looking front-plates.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: what is a " network renderer ", posted on December 12, 2014 at 08:50:58
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
 Hi and thanks a lot for the kind explanation
A very interesting approach indeed
But also very difficult and for expert like the choice of the OS
I read that Linux, for instance, runs also with low resources
Does this maybe mean that is more "effective" of the others ?
Does this make it a better OS ?
I am thinking to try Ubuntu but i am quite scared
I would only need a good SW to play media files then
Then i have also to check if my pc is compatible
For instance the NUC has no official drivers for Ubuntu
Is Ubuntu a better OS than win 7 64 bit ? i am not able to slim win 7 down so i am referring to the recommended installation of the OS
Thanks again.



Kind regards,
bg

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 12, 2014 at 09:57:05
jkeny
Manufacturer

Posts: 502
Joined: May 4, 2001
 Yep, John Swenson has called this packet noise (maybe packet jitter?) & it is really the result of the receiver chips self generated noise when packets arrive & processing of these packets occurs. The concept being that this burst of processing causes a current draw on the PS which can effectively result in noise on the PS/ground plane & this noise effecting other parts of the system that are also using this PDN (power Distribution Network).

One way of addressing this is to read the whole audio file into local RAM at the DAC & closing down the connection before processing of the audio file from RAM by the DAC chip.

Another way would be to attempt to kill any possible PDN noise when processing this bursty data

Or a final way, might be to ensure the packet bursts do not have a frequency that effects the audio band directly?

Edit: I see my points were already made - sorry for the noise :)
There may be another issue - the signal integrity of the waveform that represents the digital bits? Could a worse SI waveform result in a different sound to a good SI waveform because of similar processing issues in the receiving chip?

My thinking is that DACs connected to computers are effected by a mix of 3 possible issues:
- noise conducted via the wire connection (usually common mode)
- bursty packet self-generated noise
- signal integrity self-generated noise

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 12, 2014 at 10:08:39
Tony Lauck
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Posts: 13629
Location: Vermont
Joined: November 12, 2007
 Noise can be coupled at least three ways, through the air with cables acting as antennas, through the power wiring and through the signal cabling. You can test (and rule out or rule in) the first two possibilities by running the computer after the streamer has been disconnected from the network. (You may have to fake it out so that it thinks it's still playing, details would depend on system and network.) Shielding on the Ethernet cables will definitely help but there are various ways their effectiveness can be reduced.

Getting to the third possibility, different software in the computer or various hardware related noise will affect the speed at which the computer operates and hence the timing of packets sent through the router. If this timing is different then the router will forward packets to the streamer with different timing. The streamer gets a huge pulse of work each time a packet arrives and the required processing will create noise. If the streamer isn't isolated from the DAC then this noise will affect the audio. This is a good theory, and according to John Swensen, a theory that he has proven to apply in practice.

What this amounts to is that the streamer has a computer inside it and that computer has the opportunity to pollute the audio output of the DAC. I can't think of any way to avoid this possibility other than to isolate the DAC from the streamer. The fundamental problem is that computer components that are designed as digital circuitry are in close proximity with sensitive analog components such as the DACs master clock, converter power supply, DAC chip, IV converter and output buffer.


Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 12, 2014 at 10:35:53
Tony Lauck
Audiophile

Posts: 13629
Location: Vermont
Joined: November 12, 2007
 I'm sure some of the crypto circuit designers have a handle on this problem. I never got close to those particular spooks, however. The spooks that I did meet with in person were scary enough.

As you pointed out, there are optical transmitters and receivers that work at multiple gigabit rates. There are probably other suitable design techniques to deal with power/ground noise affecting signal transitions, or somehow decorrelating the noise from the musical signal, thereby rendering it benign. I'm a systems guy, not a circuit designer, so I'm afraid I can't help you out with details.


Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: "network rendering, streamers, music servers, mini computers", posted on December 12, 2014 at 10:45:30
Sprezza Tura
Audiophile

Posts: 4585
Location: New York City
Joined: August 24, 2012
 Thorsten's iFI iUSB creates isolation between computer/streamer and DAC.

 

RE: a brand new term, designed to confuse everyone, posted on December 12, 2014 at 11:04:59
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
Hi and thanks and sorry for the belated reply
Now i have understood and i have to say that if keeping things simpler is better these network streamers makes a strong sense.
The average guy has audio, video and internet on the same pc.
I am convinced now that internet must be absolutely avoided
Video maybe can live together with audio
Audio only would be the best
So for audio streaming only the HW can be quite reduced
Personally i am following a lot the Android streamers
The OS is very fashionable and there are many update
My next idea would be to try an Android media streamer with a usb dac
Or viceversa if only i could find a usb dac with Android drivers ...
Thanks again.

Kind regards,
bg

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 03:52:07
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

> I'm sure some of the crypto circuit designers have a handle on
> this problem. I never got close to those particular spooks, however.

I suspect they do, from a different angle. But Deep Crypto scares me, the people into in are a bit odd.

> As you pointed out, there are optical transmitters and receivers
> that work at multiple gigabit rates.

But not necessarily ones optimised to carry 50MHz/50MBPS signals with low jitter, or at prices that make inclusion in relatively inexpensive commercial equipment feasible.

> There are probably other suitable design techniques to deal
> with power/ground noise affecting signal transitions, or somehow
> decorrelating the noise from the musical signal, thereby
> rendering it benign.

Yes, but that does not really help with things that can only isolation (or breaking the noise loops in other ways) can fix.

What we (Computer Audio) need are commoditised USB2.0 High Speed isolators OR good isolators for I2S style digital signals up to 100MHz that do not operate based on RFI producing principles and have low jitter.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 09:41:08
Tony Lauck
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Posts: 13629
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 The crypto people are very much concerned with jitter on their signals. Jitter provides a "covert" channel that can leak secret information, bypassing the encryption algorithms. I'm sure they work with signals that are vastly faster than 50 Mbps these days. As to how fast they want to go, I was told , "ten times faster than the fastest that is possible".

You may find this article interesting.



Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 10:39:18
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
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 Tony,

Interesting, but fails to answer "commoditised solution".

Now I remember precisely why I find Deep Crypto so scary...Thank you not for reminding me.

Actually, I gave up on anything serious crypto in the 90's, switched to everything in the open and use cypher instead. Cypher cannot be broken mechanically, though it can be compromised (e.g. the Midway affair in WWII).

In fact, Crypto did not work well even in WWII, Enigma anyone?

In the presence of near turing capable analytic engines almost no cryptography is uncrackable.

If you ever spend time in China ( I get to go one or two times a year - married a chinese gal), the level of deep package inspection the government there employs is something else. They leave my VPN connections alone as long as I do not do anything "naughty" (meaning I am trying to look up something their censorship system think is, not Porn or the like, not even politics mostly).

But as soon as I do - my VPN connection is choked off.

0kbps. Not cut, mind you, choked off.

Then I have to change the server and reconnect. And get choked off 3 minutes later again.

And I am not using ordinary or free VPN's either (nor am I one of the usual gibronis, I use near mil spec stuff!). Because of the high annoyance factor of this I plugged about any possible leak on my machine and they still get through all the ICE, somewhere...

They must have machines that eat 256 Bit keys for a light snack, at ISP level too, to monitor what is inside my VPN Tunnel. Scary. Expensive.

Back to music.

Deep Crypto is too scary. WAY TO SCARY.

Commoditised Isolation Solutions please.

As in "Fast(ish ~100MBPS), Low Jitter (< 20pS would be nice), Cheap (say 5 USD for EIAJ Dual Mono)".

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

what is a network renderer:, posted on December 13, 2014 at 10:42:28
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 It is an Ethernet interface rather than a USB interface. Takes packets off Ethernet and buffers them, reclocks them and reformats them. Then outputs on I2S, S/PDIF or AES/EBU. If you don't know what Ethernet is, it is the wired version of WiFi. Your router usually has several Ethernet connections.

Can be an external device or designed into a DAC. It can be designed with many different embedded processors running various operating systems. It is not usually a general purpose computer.

 

RE: a brand new term, designed to confuse everyone, posted on December 13, 2014 at 10:46:49
audioengr
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 The term Network Renderer was chosen by the committee that developed the DLNA standard.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 11:04:32
audioengr
Manufacturer

Posts: 6017
Location: Oregon
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 "Common digital isolators in the Digital Audio section can easily add several nanoseconds of jitter, so they are rare. "

Not that rare, and they don't need to add any time delay at all. An experienced digital designer can do it.

However, even with complete galvanic isolation, the power supply on the PC and the playback software still matters. Ripper software still matters. Don't ask me why...

Steve N.

 

Correct, posted on December 13, 2014 at 11:06:33
audioengr
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 Correct, I2S is where you isolate USB interfaces and any other interface for that matter. Works like a charm.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 11:09:27
audioengr
Manufacturer

Posts: 6017
Location: Oregon
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 Most XMOS designs only need 24.576MHz across the I2S interface. This is easily isolatable. Why do you need 50MHz?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 11:15:54
audioengr
Manufacturer

Posts: 6017
Location: Oregon
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 You blame reviewers? In my camp, Async USB is affected by the computer source due to common-mode noise. Some USB ports on computers are better than others in this regard, and better power supplies probably help here. USB common-mode filters help a lot. Galvanic isolation fixes it.

If the USB port on the computer is really poor, there may be high error rates too. Gordon has supposedly measured these. I cant seem to get the same result when I make the measurement though. Errors seem to be rare, but maybe I just have really good computer USB ports. I stay away from Dell and others that are notorious for cheap I/O infrastructure.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 15:10:51
Sprezza Tura
Audiophile

Posts: 4585
Location: New York City
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 Reviewers are low hanging fruit..an easy target.

I don't take reviewers seriously enough to assign them blame.

They are literally the blind leading the blind in most cases.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 17:58:19
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 I actually agree with you on this one. Their systems are equally poor too. There are a few exceptions though.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 22:37:28
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
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 Steve,

All the isolators for digital signals I have encountered are subject to delays, delay skew between channels and most crucially delay skew on each transmitted bit. This is due to their fundamental principle of using a high frequency carrier and some kind of magnetic or capacitive coupling. Even optical systems are subject to some delay and skew.

But good to you if you have something that isolates (even at RF) and is not subject to the usual limitations.I hope you use it extensively to gain a competitive advantage.
Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 13, 2014 at 22:39:21
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Hi,

> Most XMOS designs only need 24.576MHz across the I2S interface.

Well, I need more than that, ok?

> This is easily isolatable.

Depends on your definition of "easy" and "isolate".

> Why do you need 50MHz?

Now that would be telling, no?

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 14, 2014 at 11:36:39
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 Certainly isolators insert delay, but so do flip-flops and clock periods are delays too....

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 14, 2014 at 11:38:03
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 Look, I also use 45 and 49MHz MCLK, but I don't need it in the I2S XMOS interface.

 

Thanks: The foundation of superior playback is hardware, posted on December 15, 2014 at 10:46:32
Sordidman
Audiophile

Posts: 13665
Location: San Francisco
Joined: May 14, 2001
 Consumers tweaking computers and becoming their own "designer" or "manufacturer" is a recipe for disaster.

When we push toward superior playback with our computers that are not designed for high end audio playback, (indeed designed to be the antithesis of great playback), we are on a fools errand.

In no world is a Mytek DAC EVER going to be as good as anything that says Meitner on it at 10 times the price. The elements that go into building a great DAC have stayed the same since 2000.

This is also the case with transports. No computer can ever be made into a SOTA transport.

Most people here are not interested in SOTA, and that's fine. But traditionally, SOTA tech & ideas "trickle" down to the rest of the high-end and even lower. The examples of this, are almost too numerous to mention.

I contend that before one wastes time trying to violate a computer, that one does some basic Squeezebox optimization, or picks up a Sim Audio Mind, and does some comparisons.



"Asylums with doors open wide,
Where people had paid to see inside,
For entertainment they watch his body twist
Behind his eyes he says, 'I still exist.'"

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 15, 2014 at 23:28:54
Scrith
Audiophile

Posts: 1169
Location: Los Angeles
Joined: July 19, 2005
 Or you could use a DAC that does that instead of that hypersensitive Empirical Audio crap.

 

RE: what is a network renderer:, posted on December 16, 2014 at 03:36:21
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004


Hi thanks for the kind reply and sorry for the delay
Does this network renderer have to have an internal dac ?
because if it is a network streamer many of them rely on external dac, with usb input or spdif input.
So the interface issue is still present.
Can you give me some commercial examples ?
Thanks again.

Kind regards,
bg

 

Manufacturers make this call -t, posted on December 16, 2014 at 09:53:47
Sordidman
Audiophile

Posts: 13665
Location: San Francisco
Joined: May 14, 2001
 .

"Asylums with doors open wide,
Where people had paid to see inside,
For entertainment they watch his body twist
Behind his eyes he says, 'I still exist.'"

 

RE: what is a network renderer:, posted on December 16, 2014 at 12:49:32
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 This renderer evidently does not have an internal DAC. Another is the Rendu:

http://www.rendu.sonore.us/rendu.html

 

RE: what is a network renderer:, posted on December 16, 2014 at 13:31:52
beppe61
Audiophile

Posts: 4705
Joined: January 29, 2004
 Hi and thanks for the suggestion but in this case we can have again the issue of the interface at the spdif out
A nice thing instead would be a renderer that connects via ethernet (or wireless) to a LAN but output directly an analog signal
That would avoid any interface issue ?
No usb and no spdif ... only analog outs
I wonder if renderers with analog outs exist
Thanks again.
Kind regards,
bg

 

RE: what is a network renderer:, posted on December 17, 2014 at 11:07:40
audioengr
Manufacturer

Posts: 6017
Location: Oregon
Joined: April 12, 2001
 You are talking about a renderer interface on a DAC. Sure, they exist, but the DACs are usually sub-par. I believe the Sony streamer does this. Wireless can be added with an external device to a wired-Ethernet device.

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 17, 2014 at 14:00:00
Tony Lauck
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Posts: 13629
Location: Vermont
Joined: November 12, 2007
 "Common optical isolator are way too slow for the sample rates I run my stuff at."


Here you go. Even a model where you can run the clock in the reverse direction without requiring a separate chip. (Of course this is only a spec sheet, may be useless marketing BS.)

Yes, you will have to reclock it.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

RE: An insolent provocation .... if a usb dac is very well design (and built) the pc quality should not matter, posted on December 17, 2014 at 17:11:49
Thorsten
Manufacturer

Posts: 4209
Location: Somewhere nice on planet dirt
Joined: September 25, 1999
 Tony,

I am familiar with NVE's isolators (and most other from any major manufacturer). Please enquire into the operating principle, then you might see why having these can be worse than having no isolation.

Thor

At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?

 

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