Perceived SQ differences playing local files

[the_bertrum]

Files are read from storage and transferred to host memory buffers using bulk data transfer protocols and thus with data integrity. The buffers are then read and transmitted to the audio device over USB or I2S connections using either Isochronous Transfer Mode or I2S serial transfer and thus with best effort delivery and no error correction or retransmission.

Streaming media protocols are a bit different and are designed for low overhead data transmission between hosts over a network connection. Small amounts of packet loss, packet sequence errors and and data corruption are expected and can to a degree be compensated for using various methods. Typically Real-time Transport Protocol (RTP) is used over a User Datagram Protocol (UDP) transport. UDP doesn't provide any error correction or retransmission but RTP does provide some amount of data integrity, timing and delivery handling.

moOde's Multiroom Audio feature is based on an RTP/UDP stack.

Links
https://en.wikipedia.org/wiki/Real-time_...t_Protocol
https://en.wikipedia.org/wiki/User_Datagram_Protocol

'Tis as I thought, files are files until they are streamed, and in my day to day use case that streaming is between memory and the DAC.  I shall continue to temper my experiments with that knowledge.

[michaelagiles]

My observation is that SQ discussions often get derailed by posts asserting that its just placebo effect or some other tricking of the mind. Thats a valid point of view but rarely do these types of posts just leave it at that. They typically wade into the swampy area of rudeness, misinformation, trolling, insults and so on. Not good.

Beyond a certain number of comparisons, no placebo effect remains.

But so few people know this in audio.
Which I find strange.

Can you expand on this? Or give a reference to explore? I have never seen this concept before and I am very interested in its implications.
Thanks!
MG

[Gekel]

On a philosophical note, let us accept that audiophile truth does not exist and that audiophiles per definition are comparing their placebo effects in this hobby where we are all aiming for the optimal goose bumps producing illusion.

Not really, not at all. I try to get a good sound quality and I am willing to invest some money to achive this. However I don't plan to spend money on snake oil and make people happy who sell me a cable designed and used to transfer digital data for a three- or four digit dollar price, just because of some audiophile goose bump placebo effect which goes away as soon as I leave the placebo area and look at the physics.

People who buy such cables are the same kind of people who think they get better print outs with much darker parts and much more details in the dark grey areas by exchanging the (working) usb cable the printer is attached to the computer with an audiophile one.

Remember: there is a reason why all these companies broadcast claims about the wonders they can do with the equipment, but in no case you will find an objective comparison of the sound quality with vs. without such a piece of gear, despite having microphones on hand which are much more sensitive than any human ear and the very simple possibility to analyse/compare two sound characteristics.

[Gekel]

You don't need to be a consumer protection hero, nor do you need to piss on someone else's approach to a hobby. These accusations of delusion, snake oil, and such are derogatory in the sense that you are claiming others are so gullible or easily mislead, when you don't actually know that to be true in any specific instance.

There is an easy solution - measure it. Measuring the sound output of equipment is very easy. All you need is a sensible microphone and some software. These kind of frequency analysis curves are standard, like done here: http://www.learningaboutelectronics.com/...io-signals

If you can hear a difference in the sound quality, it must be visible in the frequency spectrum. There is no voodoo behind this, just simple physics on how sound is transferred in air to your ear. Yet I have never seen anyone who sells these expensive parts (cables, dedicated RAM modules, audiophile wifi repeater, network switches, ....) to come up with any prove, while on the oposite side (check the audiosciencereview forum) there are tons of tests where they debunk these claims.

Some of the many ones:
Do Audiophile Network Switches Make a Difference? - https://www.youtube.com/watch?v=BHPwPRLxDWc
Do USB filters make DACs sound better? - https://www.youtube.com/watch?v=RulAcLrnPkA
Do fancy audio cables make a difference? - https://www.youtube.com/watch?v=dLghg0QXPzs
PS Audio Noise Harvester Review - https://www.youtube.com/watch?v=6Xbc2-wrnBc

My favorite of all: https://www.youtube.com/watch?v=w31DQniFSEs - a blind test between a HQ digital cable and a cheap one which you can do on your own. I can only recommend to listen, compare the sound quality between the cables and then in the end look at the technical details of both of them.

But I must admit, something like this here looks/reads much better: https://hifireference.com/hifi-reviews/a...omparison/ - the only backdraw is: only "blabla" with someone describing his feelings, but no measurements at all.

And yes, I believe I am kind when I warn people of blindly following whatever they find on the net, because it can and will cost them a tremendous amount of money which can be invested somewhere else, like in better loudspeakers or a different amp.

[MikeyFresh]

You don't need to be a consumer protection hero, nor do you need to piss on someone else's approach to a hobby. These accusations of delusion, snake oil, and such are derogatory in the sense that you are claiming others are so gullible or easily mislead, when you don't actually know that to be true in any specific instance.

And yes, I believe I am kind when I warn people of blindly following whatever they find on the net, because it can and will cost them a tremendous amount of money which can be invested somewhere else, like in better loudspeakers or a different amp.

Except that no one said they were blindly following something found on the net, there was one tiny mention made about trying something, and that post even included a reference to being careful about succumbing to a "placebo effect" or something to that effect.

You can certainly leave that alone and not get up on a soap box to preach to no end, can't you? If someone states they wish to simply "try something", why does that need a rush to conclusion by you that they are in great need of your careful guidance, otherwise tremendous amounts of money will no doubt be wasted?

Further, my post indicated you had run right past the actual message of "be kind" that was in one of the replies to you. This rigid and condescending finger pointing at wide swaths of this hobby is unnecessary. Nobody likes a know-it-all is what I'm trying to say, and there are other much more appropriate places such as your beloved ASR for that kind of never-ending "measurements and DBT or it doesn't exist" derogatory groupthink. You don't need to post a bunch of links here in responding, that's just more preaching and teaching that you seem to have concluded everyone else needs, when you don't actually know that to be the case at all.

Once again, I'm pretty sure you will insist on the last word here, but let's just see if you can somehow take the high road and let it go at that? At this point I'm doubtful.

[Tim Curtis]

@Gekel I'd suggest that you start a new thread if you want to see whether people want to discuss measured vs perceived SQ or anything along those lines. Continuing to spam this thread with the same point and over again is leading toward trolling.

[charlesky]

There's a great article by Steve Guttenberg that should be read by anyone who's convinced something has made their system sound different.
No-one could possibly accuse Steve of being a rigid objectivist.

https://www.stereophile.com/content/magic-moment
"I remember the Tuesday night that music broke free of my hi-fi. ... I swore I'd never have to change my system ever again. The sound was perfect.
Wednesday eve was a different story. Some of that magic had vaporized. Mind you, I hadn't changed a thing—no cable swapping, no adjusting of cartridge VTA, no monkeying around with DAC filters, no nothing."

The most important part of subjective impressions is the subject, i.e. the person doing the listening. And we're changing all the time. I've experienced exactly the same phenomenon Steve described countless times.