Airplay & downsampling

There is your reply, Vanerp. Don't know why it didn't show up until I posted another myself. Thanks again, agian. :-)

I stream wired to my Denon AVR using the 'Airplay' and 'DLNA' protocol. The difference between wireless and wired is amongst others very depending on bandwith. On my Denon it shows the Streaming quality in %. In Streaming CD quality (Apple Lossless, 16 bit 44.1 khz) I see that wireless the indicator sometimes goes down to 30% with interuptions. It's very hard to reach 100% unless the wifi antenna is very close to the wireless airplay device. Wired this is not an issue.

Even more, I also stream locally 24bit / 192 khz files to my Denon. When I still had a wired 100 mbit network I also had dropouts when my kids were exchanging/downloading files on the local network.

Changing the wired network to 1Gbit solved the issue completely.

Another thought, Audiophiles spend lots of money on cabling (also for digital connections as HDMI)...

I think there is a difference between iTunes Airplay and System Airplay. When you set system audio to airplay, the sound quality is definitely improved.

Open Audio-MIDI Setup and choose AirPlay. You'll see that the only option is 16/44.1. It downsamples (or upsamples) everything to those rates. No need to do tests connecting Apple TVs to DACs; you can see that you can't output anything else.

The very fact that every single one of you CANNOT TELL BY EAR whether or not iTunes, Airplay, etc. is actually outputting 24-bit audio to your DAC is a tell tale everything that IT DOESN'T FREAKING MATTER. I'm converting records myself right now and I have a PreSonus for an input (I recorded my own album using it and Logic Pro 9) and I can sample 24/96 no problem. I have done so. I've converted and A/B switched to my wit's end and it sounds exactly the same. As an electronic engineer, I knew this had to be technically true given the source alone (records simply don't contain anywhere NEAR 16-bits of dynamic range, let alone 24-bit) and the human ear simply cannot hear above 20kHz even when you're young and have full hearing. It's just not possible. The only issue would be aberrations caused by brick-wall type filtering, but that was solved long ago in the digital realm with oversampling.

The human ear can hear perhaps 18-bits of resolution maximum and that's going from the quietest audible sound to a 747 at take-off in an instant! Who in their right mind would WANT an an album to do that? Throw in the loudness wars (which affects LPs made today too) and there is no way on earth most albums will even approach the 75dB of possible dynamic range the LP is capable of with the best equipment, let alone anything needing anywhere NEAR 24-bits (it is good to use 24-bit while recording as you can be pretty darn sloppy with your input gain levels to avoid any chance of clipping for any given record as 45's are typically MUCH louder than 33.3 LPs (being an analogue, the greater the dynamic range versus the surface noise floor, the louder the output signal on a record player and thus the lower the surface noise you'll hear on playback allowing quieter sounds to float above the floor whereby they would be below it with lower overall output and the same dynamic range being sent to the cutter.

The bottom line here is that it's a good idea to record at 24/96 (whether vinyl or an album straight into Logic Pro), but the final mix can easily be sent to 16/44 and you're not going to miss a thing, whether you believe it or not and that includes the Eagles album someone mentioned in the thread. Make your OWN AAC file from that 24/96 file and try to hear the difference then. You can't compare the iTunes version (sourced from the master tape separately and remastered) with a vinyl rip. Even if the vinyl rip sounds better (and it is possible depending on who remastered the album and how badly they did it and also what your definition of "better" is when it comes to something subjective like sound, compression and euphonic distortions.

Even so, there is no technical reason why an AppleTV or Airport Express shouldn't be able to handle 24/96 or even higher over HDMI. The ONLY problem is the output drivers made for iOS (the first Gen AppleTV can easily output 16/44, not just 16/48 and with some driver changes (e.g. CrystalUbuntu with XBMC), it can output 24/96 all day long over the SAME HARDWARE. It is no different with iOS. Apple is simply TOO LAZY to bother. They don't care. They just now finally got around to adding iTunes Extra support to AppleTV Gen2 and Gen3 and it's been around for nearly a half decade on the 1st Gen ATV! *** were they waiting for? What about iTunesLP? Again, supported on ATV1 and not on anything else. If people want 24/96 support in those devices, they need to get together and outright send huge numbers of feedback requests for it. Apple seems to only respond to massive requests for features, not typically just a few or I'd have 44.1 support (for DTS Music CDs) in ATV Gen2 and Gen3 (works fine in Gen1).

I can tell you this much about Airplay handling. If I send a DTS Music CD (44.1kHz) to an ATV Gen2, it will not output the signal correctly because it sends out 48kHz upsamples to its own output. HOWEVER, if you then take that signal and instead redirect it from the ATV2 to output to an Airport Express or a Gen1 AppleTV, the DTS 44.1kHz signal will be 100% intact. In other words, I select a DTS CD track from my iTunes library server to play on ATV2, but then redirect it to a Gen1 ATV and it will have the DTS Signal still intact and play correctly. It upsamples ONLY right before outputting it from the Toslink or HDMI port. Again, it's simply an iOS driver issue. It could have been solved YEARS ago. If the rumors of an iTunes "HD" music store every come true, they will probably fix all these things. But given the only 24/96 sources out there are from 3rd parties and/or your own creations or recordings, they don't give a crap. They want you to buy ALL your music from them, even though "Mastered for iTunes" means COMPRESSED TO DEATH. But in fact, the only reason many LPs have more dynamic range than typical CDs is because they come from an era pre-dating the loudness wars where many albums actually strived for a decent amount of dynamic range. The fact an LP with maybe 50-60dB of dynamic range beats a CD that can have 96dB (more with noise shaping like SBM) is simply a testament to the fact that the Music Industry has its priorities jacked up. They should have put a "dynamic range compression" button on all music players (especially car and portables) with a slider setting and then people could just compress their own albums to death if they're in a noisy environment. I remember people saying Pink Floyd's A Momentary Lapse of Reason (recorded digitally save the percussion) sounded awful and was digital's fault. It doesn't sound awful. It's more dynamic than any Floyd album before or sense, but you have to turn up the volume control to actually HEAR it properly. People don't get that. They they LOUDER output relative to other albums = more dynamic when in fact it's usually the opposite (i.e. only the loudest part should reach the maximum level output or just below it).

Hearing by air conduction is limited to an approximate 20 kHz but hearing by bone conduction extends to 100 kHz and beyond. The eardrum is one of many ways to perceive sound. Furthermore, an extensive use of EEG tests would demonstrate extraneous brain activity between two recordings recorded at different frequencies. Such tests have been performed for cognitive purposes, the outcomes favour sound reproduced above 26 kHz impacts perception of sound quality.

Obtaining 24bit 44.1 kHz or higher through Airplay is not possible... (currently)

Conundrum: obtaining 24bit 44.1 kHz or higher over airplay

Conundrum: Airplay executes 16 bit 44.1 kHz

Current Option: (Up-sampling) = $€£

As stated by Kirk McElhearn there is no other way to obtain a higher resolution other than (up sampling)

…………………………….

Airplay ≤ 16 bit 44.1 kHz

Refer to earlier post

Maybe you would like to back up those claims with some actual proof? I can turn up my stereo as loud as it will play with a 20kHz test tone and at my age, I can't hear it. We're talking about 115dB+ output here. Shouldn't my bones being letting me hear it? Do I have to stuck my chin against the tweeter? If so, that's not very convincing evidence that it makes one whit a difference with normal music at normal volumes.

Are you Kidding, I'm into good Stereo, have a Excellent Stereo Equipment, main unit my Receiver Denon AVR- 3806, yes it's showing it's Age, but the Sound hasn't Degraded at ALL, sounds the same as the First Day I been using it. Cable's High End, RCA's pure Silver, yes and there Locking connections are Pure Silver, got these when this Company first came out, Ridiculous Price so I jumped on that, all my Components are connected with these. All in One Cd, DVD, BlueRay Player is Oppo, you were saying My Hearing can't Distinguish from CD Quality to DVD Audio 24/96, you must have some Really BAD Ears, there is a Huge Difference in Audio Quality, better all around you can feel the BASS better the Tonal Balance is much Cleaner. I also have Super High End Music, lets call it for what it is DVD Audio 24/192, Sounds like the Band is right in Front of me, with a Cd play, sounds Distant, hardly any Definition. So to say there's no Difference, I'd have to Disagree, buy High End your won't be Disappointed the only Trouble is Now getting that High End to your Stereo, everybody here Finely Realizes you just Can't Stream A Higher Rate to your Stereo Using Airplay.

I would burn my Music to a DVD Disk, well that Company is probable the Worst and it's the only Company for Mac Users, Disc Welder, right now they haven't upgraded to Maverick, now there's Yosemite, so My Hopes there going to upgrade is Zero. The only Option I'm seeing is buying the Disc, there are allot of High End Dvd Audio Web Sights, where you can purchase the Disc.

You need to learn the difference between a good mastering and sampling fidelity. The only reason some 24/96 recordings sound better is they are better mastered. Go read about Nyquist sampling theory and you will see you are just plain WRONG. 16/44 is more than adequate to perfectly reproduce the human hearing spectrum to any sane volume and all audible frequencies. It's simple to prove. You are confusing a good recording with its sampling rates. Convert it yourself to 16/44 with proper software and you won't be able to tell a difference.

Hi guys, I was wondering if someone can tell me if the Apple TV 3gen is able to output via Toslink untouched audio from Shared Itunes Library (no Airplay which I know is limited) byassing its DAC just like we can do connecting the Mac to an Hi-End external DAC with USB cable.

To be more precise: if I plug my Mac to my external hi-end DAC with USB cable, the integrated low quality DAC of my computer is totally bypassed and every digital audio file is sent as it is to my external DAC which does the conversion.

If I connect my Apple TV 3 with optical cable to my external Hi-End DAC will the same thing descripted above happen? Will the audio file be sent as it is to my external DAC?

Any ideas on streaming higher quality music? Airplay stream quality is below my desirable prefernce. My Cd player (DVD player 96khz 24bit converter) sounds much more dynamic and clear. Frequency response is better and with less distortion. Airplay sounds like I'm listening through speakers with a half inch thick foam mattress.

HI guys,

if you are looking for a highly audiophile solution with airplay check out LeAudiophil from Hartmut Alt in the german open end board or if you want to spend more money for the same kind of soundquality the LaRosita gear.

br

flo

How to integrate Hi-Res audio with the world of Apple

I've gone through a lot of this, here are my insights:

1. Hi-res audio (24/96 or 24/192) is a very significant improvement over cd-quality (16/44.1) ...IF you have a high quality playback system.
2. iTunes can support hi-res files...sort of. It works much better if you use a third party app to make it work properly.
3. Airplay solutions via AppleTV or Airport Express are fairly slick logistically for distributed audio, but do NOT support anything better than 16/44.1 resolution. This means you need something that actually runs iTunes in order to output hi-res audio...like a Mac Mini or other more powerful Apple computer.
4. Putting the pieces together for hi-res AND distributed audio is currently a bit of a hassle, but very possible.

Here's one way to go about it (not the only way, but one that works somewhat reasonably well...but its a little expensive).

1. Put all your iTunes library on a central, network accessible HD. You can use a Time Capsule, or any sort of apple-compatible NAS solution.
2. For every system where you want Hi-Res audio, you will need a Mac Mini. You can get by with the lowest spec available.
3. For every Mac Mini, you will run an instance of iTunes dedicated to that system. In order to really play those files properly, you should add an app that will "force" iTunes to output it's digital stream at the native level of the track you are playing ...which might be 16/44, 16/96, 24/88, 24/96, 24/176, 24/192, or who the **** knows what...there's a tone of possible formats (I use Bit Perfect for this, but there are other possibilities as well.. I use AIFF files, which requires a lot of storage but work best for me. You'll want to make sure your audio system has a high-quality, asynchronous DAC capable of up to 24/192 resolution. Take a look at this article for details on how and why to do this. http://www.psaudio.com/ps_how/how-to-build-a-music-server/
4. For other, non-hi-res zones that you want to feed, you will need (yet another) iTunes source...I use another Mac Mini. This source will play through the standard airplay setup with airport express or AppleTV, streaming to zones however you see fit.

The biggest issue with this set up can be library management...you have a central repository of files to play, but if you do much custom library management then I know of no way to synchronize these changes across the fistful Mac Minis that run various zones.

Also, if you want synchronized audio playing through every zone (house party!) you run into some difficulties there as well...you can't readily synch the hi-res systems with the airplay systems. I personally get around this by having not only a Mac Mini for hi-res audio, but also an Airport Express that feeds a different input for the Hi-Res systems. Yeah, not a typo. (if anyone has a better way to do this, let me know).

The above set up gives you:

Awesome Hi-Res sound quality in places where you need/want it and have the audio system to make it worthwhile, AND full zone control for the whole house when you want that instead.

Just for reference, here's what I am using:

Time Capsule 2TB - file server (and this network and HD is dedicated entirely to the iTunes library and streaming system).

Hi-end system 1: Mac Mini + Musical Fidelity M6 DAC + Musical Fidelity M6si Integrated amp + Revel Gem 2 speakers*

Hi-end system 2: Mac Mini + Peachtree Nova 220se Integrated amp + Joseph Audio Pulsar speakers (+Airport Express for whole house synch)

3 Air play zones: 1 Mac Mini as a server, plus each zone has Airport Express + Nad 3020d + Linn Tukans or some decent in-wall speakers.

*note: I don't even have a monitor hooked up to the Mac Mini...I just use Apple Remote on an iPad for iTunes control.

A note to folks who doubt the difference between hi-res and cd-quality files: When I first set up this system, I just had the Musical Fidelity + Revel set being fed directly by a Mac Mini. I later moved the Mac Mini and started streaming to a bunch of different zones. I had no idea that the airplay streaming was going to downsample to 16/44.1 ...so as far as I knew, I thought I was still listening to Hi-res. But holy sh*t was obvious that something had changed for the worse! I spent a ton of time trying to figure out what had gone wrong, even thought my DAC might be broken for awhile...but no, it was simply the difference between Hi-res source and CD quality source.

I'd call that a double-blind test with the deck stacked against me...I had every reason to believe I was actually listening to Hi-res, but it was obious that the sound was far, far worse. Now to be fair, the Musical Fidelty + Revel Gem2 system is extremely high-end, and that makes a huge difference in your ability to tell the difference with Hi-Res. Could I tell on the Nad 3020d + Linn system? Yeah, maybe on a side by side comparison, but the difference is remarkably more subtle.

At any rate, hope this helps someone...and I hope Apple eventually figures out how to support Hi-Res is a more robust way 😟

Good luck!

Wow thanks a lot for this great idea! But instead of using a second macmini for highres streaming and a dedicated DAC, i would highly recommend the two alternatives I have mentioned before. With my LeAudiophile I am getting a much better sound than with an Oppo 105 connected directly to the mac via USB.

So anyone interested in highest sq over airplay should give it a try :-)

the best thing is, that all music material will sound so much better, not only the minor available high res ones ....

br

flo