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Airplay Sound Quality-does a wireless transport make any difference if you are not using a dac?

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Andrew Everard
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RE: ifor RE: ifor

maxflinn wrote:
Andrew, you said yourself that a digital cable cannot improve anything, so how can a streamer do so?

I said that a cable cannot improve things, but can minimise losses so that the receiving device has less work to do. The same applies to a well-implemented streamer, able to process the incoming data to a higher standard and thus present a 'cleaner' digital data-stream to the digital-to-analogue conversion.

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maxflinn
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RE: ifor RE: ifor

Andrew Everard wrote:

maxflinn wrote:
Andrew, you said yourself that a digital cable cannot improve anything, so how can a streamer do so?

I said that a cable cannot improve things, but can minimise losses so that the receiving device has less work to do. The same applies to a well-implemented streamer, able to process the incoming data to a higher standard and thus present a 'cleaner' digital data-stream to the digital-to-analogue conversion.

There's no such thing as a cleaner digital data stream  Smile

It's either corrupted to such a degree that it cannot be fully reconstituted - and you won't hear the music, or, it can be fully reconstituted - and you will hear the music,

Nothing, no cable or streamer, can improve a digital data stream, either 100% of it is converted by the DAC, or there is a failure as the DAC (or codec in the case of HDMI) does not have all the data to process  Smile

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Andrew Everard
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RE: ifor RE: ifor

maxflinn wrote:
There's no such thing as a cleaner digital data stream  Smile

It's either corrupted to such a degree that it cannot be fully reconstituted - and you won't hear the music, or, it can be fully reconstituted - and you will hear the music,

Nothing, no cable or streamer, can improve a digital data stream, either 100% of it is converted by the DAC, or there is a failure as the DAC (or codec in the case of HDMI) does not have all the data to process  Smile

I said 'able to process the incoming data to a higher standard and thus present a 'cleaner' digital data-stream to the digital-to-analogue conversion' – in other words, do a better job of reconstituting (to use your word) the incoming data, reducing or (ideally) removing the effects of jitter, transmission losses and the like.

I'm not talking about 'improving a digital data stream': I'm talking about doing a better job of putting right the damage done further upstream in the chain between the source of the data and the DAC.

Anyone believing in 'perfect or not there at all' has never heard the differences between CD players, seen 'sparklies' on a TV screen or heard 'bubbling mud' on a DAB transmission.

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jcbrum
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RE: ifor

Andrew Everard wrote:

I wasn't aware we were discussing Malcolm, nor indeed am I aware of him making a faux-pas.

 

You must be one of the few 'computer-audio' enthusiasts in the world who isn't aware of his almost universally derided remarks concerning changing his hard-drive data cable to improve his audio quality.

It's a classic example of digital cable foo, which has already been discussed ad-nauseum, hence my remark that whilst it was relevant, there's no mileage in discussing it further.

 

Andrew Everard wrote:

I guess it comes down to whether one is prepared to settle for 'merely good enough', or endeavours to achieve the best one can. I mean, I listen to podcast radio programmes in the car when I am commuting, most of which are at very low data-rates, and they sound fine. But play them on a decent home system, and their limitations are all too apparent – a case of 'merely good enough' not really being good enough.

 

I think that has more to do with the compression technology, and the low data rate, employed, rather than the fact that digital propagation is employed.  If what you said was generally true of digital transmissions, the internet, and world-wide data systems, and music downloads of any type, wouldn't work properly.

Andrew Everard wrote:

And how on earth can any audible differences be due to the analogue converter – I assume you mean digital-to-analogue converter – when I'm sure I read somewhere the opinion that all DACs, provided they're implemented properly, sound the same?

 

The analogue converter, which is that part of a complete 'DAC' (in a hifi equipment sense), is the only part you can 'hear'.  It's what produces the 'analogue', - you can't 'hear' digits, and perceive music.

 

Andrew Everard wrote:

I suspect we're not going to agree on this one.

 

Possibly, but put your faith in 'a ray of light' emerging  ;)

 

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shafesk
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RE: ifor

I have never heard differences in sound quality between cd players when used as transports. There only seemed to be less skips during damaged cds. I think a good streamer might theoretically do the same, reduce the need for error correction and may bring out the consequent benefits associated with it. However, I haven't had a chance to compare a high quality streamer with my atv.

Interestingly it has been said that digital cables don't make a difference, well I use a usb b type cable with my hrt music streamer and when I use a rubbish cable I cannot even get the thing to turn on as it has no separate power supply. What I believe is happening is that the cable isn't giving the streamer enough voltage to power up and convert digital to analogue at the same time. When I charge my ipad, it takes a lot longer if I use a cheap third party cable. Although I've heard differences in spdif cables, a poorly implemented cable could in similar ways make things a lot worse (I know spdif cables don't carry power like usb cables but I MEANT IN SIMILAR WAYS!). 

Now someone is bound to come along with a counter argument, but thats about it for my knowledge so I'm waving the white flag before hand.

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Andrew Everard
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RE: ifor

jcbrum wrote:
It's a classic example of digital cable foo, which has already been discussed ad-nauseum, hence my remark that whilst it was relevant, there's no mileage in discussing it further.

So why bring it up?

jcbrum wrote:
The analogue converter, which is that part of a complete 'DAC' (in a hifi equipment sense), is the only part you can 'hear'.  It's what produces the 'analogue', - you can't 'hear' digits, and perceive music.

Ah, I didn't realise that a digital-to-analogue converter had one part converting digital signals to analogue, and another converting the analogue into analogue so we could hear it. You learn something new every day, eh?

jcbrum wrote:
Possibly, but put your faith in 'a ray of light' emerging  ;)

I have not faith in Madonna whatsoever.

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jcbrum
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RE: ifor

Andrew Everard wrote:

jcbrum wrote:
It's a classic example of digital cable foo, which has already been discussed ad-nauseum, hence my remark that whilst it was relevant, there's no mileage in discussing it further.

So why bring it up?

Because it's a relevant example of a common misconception concerning digital cables.

 

Andrew Everard wrote:

jcbrum wrote:
The analogue converter, which is that part of a complete 'DAC' (in a hifi equipment sense), is the only part you can 'hear'.  It's what produces the 'analogue', - you can't 'hear' digits, and perceive music.

Ah, I didn't realise that a digital-to-analogue converter had one part converting digital signals to analogue, and another converting the analogue into analogue so we could hear it. You learn something new every day, eh?

 

Most hifi enthusiasts will think of a 'DAC' as a box full of electronic circuits with input and output connectors on the outside.  Inside that box will be printed circuit boards populated with electronic components, - 'chips'.

 

The actual integrated circuit chips also referred to as 'Audio DACs' usually have at least four important internal components, the signal input stage, the voltage reference stage, the clock, and the converter, which feed the output buffer stage.

 

Take as a 'high-end' example the Wolfson WM8741 DAC.    Wolfson say this . . . 

 

The WM8741 includes fine resolution volume and soft mute control, digital de-emphasis and a range of advanced digital filter responses, followed by a digital interpolation filter, multi-bit sigma delta modulator and stereo DAC. Wolfson’s patented architecture optimises the linearity of the DAC and provides maximum insensitivity to clock jitter. 

 

The emboldened bit (by me) means the converter.  You can see that there is much more inside a 'DAC' chip than just the converter.

 

JC

 

Andrew Everard
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RE: ifor

Thank you for that clarification. Now you've put the important bit in bold type, I understand the point you're trying to make.

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