CD Quality Versus Streaming Quality

Hi JPeter568,

Thanks for that great information. Your work as a senior systems engineer gives you the advantage of knowledge from a technical standpoint. Some very interesting and relevant points you make, although from my personal experience, and don’t ask me why, different players as transports do affect the sound one hears (note that I have only used players as transports, and not dedicated transports which could be a different result);

a) no noise is carried in the digital stream
b) even a modest or rather network setup, it is capable of carrying a bit perfect stream with no problem
c) Transports as separate from an external DAC will have zero effect on the sound quality

quote; “So to the original OP - my guess is that it was a difference in configuration or a setting that might have been off - certainly the dac WILL have an impact on the sound, so I'd recommend connecting a digital out on your transport, checking your settings to ensure you're streaming the same thing, and then re-doing the test. Because coming through the same DAC should be identical sound (WITH the caveat that George points out too - provided they're the exact same mix/ release of the album.)”

The test was as follows;

On my son’s system, a Devialet Expert Pro 220 driving Magico S3 through Synergistic Research Foundation speaker cables run a stream of albums on Tidal that I have on CD and them compare them. I also brought my Pioneer BDP-09fd to his house to use as CD player. We did the following;
- First test: Run ethernet cable from his router directly to Expert DAC input, then using iPad and Devialet Air, stream the songs via Airplay-Eth
- Second test; Connect Apple Macbook Air (first gen where direct USB connect possible without dongle) via USB into Expert Pro and stream same songs over USB, with the advantage of first stage MQA unfold
- Third test; Connect CD player via coax to Expert Pro to run digital stream to Expert Pro DAC, sourced from CDs or same albums of tidal streams
- Fourth Test; Connect CD player via analogue outputs running transparent ultra and synergistic research foundation i/c. In this case, the Wolfson DACs do to D to A conversion.

JPeter568,

Sir you are obviously very knowledgable as networks and systems connectivity is your professional vocation. Everything you’ve said make sense although i would have to offer an alternative viewpoint  on transports, only because i have observed the differences between several that I have. For example, as superb as the Oppo 205 and 203 are, purely as transports, they don’t sound as good as the BDP-09fd purely as transport, which produces a more dimensional and captivating sound to my ears. Again I can’t explain why. Perhaps its in the execution of the interface? As an aside, I think for 1080p, I prefer the picture and sound of that Pioneer $2,200 flagship from around 2008-2010 to the venerated (justly so) UDP205 and 203.

It stands to reason that bits is bits. Streaming should sound no different than the CD. They are both after all 1s an 0s that are checked to be bit perfect. There is of course the matter of jitter and I would suspect at the micro levels it doesn’t affect sound quality too much for the average high resolving system. But for über resolving systems that might be different.

So then, we are left with two possibilities that might account for the differences heard in the test we conducted. These differences are not massive but they can greatly affect ones enjoyment listening to music, and can be stated as loss ‘something’ especially in high frequency purity and clarity, bigger more clearly definite / solid  imaging or put another way  a more ‘definite’ presence and vitality to the sound, a more accurate less homogenized soundstage, more defined bass performance, and less ‘smearing’. Incidentally I should add, that on occasion I have heard streaming sound very very good, good enough to keep me with wine in hand sat in place for hours listening. The two possibilities as i see it are;

a. Noise, from EMI / RFI pollution
b. A compromised stream that is not full bandwidth or where compression algorithms are screwing up timing causing smear, and messing with information vital to the full sonic picture. Again sometimes the sound is better than others…

@georgehifi

The streaming companies need to give the album Cat No. with all their streams/downloads, so you can find for yourself on the DRDB if
your paying for and listening to compressed rubbish.

That would be great and should be available without question for the very reason you state. I can only speak to Qobuz, but some of the dig downloads I have purchased (new releases) have included cat numbers in the metadata. 

I don't understand for the life of me, why the f*&% complete meta data isn't part of these dig purchases.  It's not the services fault, but the labels that provide the files.

Red,
Your ASSUMING that the labels arent giving the services the data. Perhaps the info IS given and the services are choosing not to give you that info. Could be they dont WANT you to see the data so you cant do your due diligence and compare different master/remaster versions.  Certainly not saying this is true but it is in the realm of possibility.

4afsanakhan

It stands to reason that bits is bits.

Things are not always as they appear at a quick glance.

Streaming should sound no different than the CD. They are both after all 1s an 0s that are checked to be bit perfect.

That is mistaken. While outright errors on an audio CD are usually rare - there is redundant encoding of the data which are interleaved on the disc - the CD-A standard includes interpolation when an error cannot be recovered. By definition, the interpolation is an estimate and not necessarily bit perfect. ( The interpolation is needed because unlike a CD-ROM, an audio CD needs to read in real time.)

It’s easy to imagine that when streaming audio from a server farm miles away, errors could creep into the signal that would require error correction or interpolation. So it really isn’t accurate to say "bits is bits" if you're talking about audio playback in real time.

@riaa

Red,
Your ASSUMING that the labels arent giving the services the data. Perhaps the info IS given and the services are choosing not to give you that info. Could be they dont WANT you to see the data so you cant do your due diligence and compare different master/remaster versions. Certainly not saying this is true but it is in the realm of possibility.

Maybe (sounds a little extreme, but anything is possible I suppose), but given the fact that downloads from the labels / artist directly as well as the digital stores (pro studio masters, acoustic sounds any of them really), metadata in those are no better, in my experience.  Just artist, track, album etc.. minimal crap.  It should contain everything pertinent (what one would find on CD sleeve).

I've emailed Qobuz the exact question (looking to clarify cat number) and they were helpful, but I recall the response was something like that's what the label provided and they are not touching the metadata