[vitzijak]

Hi Everybody,
 
My current listening scheme is iphone 4 apple lossless files> Airplay wifi > AppleTV (latest) > optical > Bryston SP2/DAC > Bryston 6bSST > Magnepan 1.7.  It sounds nice, and gosh its convenient.
 
I have compared this to Oppo BDP 83> optical >SP2/DAC, and Oppo BDP 83> analog  > SP2 analog
 
To me, they all sound different, with definite difference in volume, and seeming difference in EQ, but I'm trying to decide if there is a definite improvement in overall SQ.  From what I have learned here it seems any decent DAC and decent bit rate will sound the same.
 
So questions:
 
1) Does iphone to wifi to apple TV optical out result in any signal degradation enough to make make a difference?
 
2) Is there any benefit to going to the wired digital player method such as Logitech Squeezebox, or even pricier Bryston BDP
 
Thanks!

 

[chewy4]

No need to worry about the sound quality of digital data unless it's giving you something to worry about.
 
If anything before the data hits the DAC is going wrong, you'll know. Basically you'll just get dropouts, maybe skipping. Or sometimes an error can happen that will force it to skip songs completely(my Xbox 360 does this some times).

 

[jaddie]

I'll go +1 to Chewy4, and add this: I use several Apple TVs, different generations, and they go HDMI or Optical out to whatever device they feed.  There are no issues with audio quality streaming from any device to ATV.  
 
I wire my Apple TVs to my network, though.  I do this for better overall performance, higher data speed is a plus with ATVs. Unless a bit of Cat5e wire is way to hard to do, it's what I recommend over Wifi.  Sometimes the advantage is small, other times it's exactly what you need to make the experience as smooth as possible.  It's never an issue of image or sound quality, it's an issue of getting things loaded fast, filling the buffer and keeping it filled, loading library data, etc.  
 
Netflix in particular benefits from fast bursts of data.  

 

[MoonUnit]

You should be aware that the Apple TV only has a 48 kHz clock for its optical out (as well as its internal DAC), so all CD quality audio getting sent through the Apple TV is resampled. This is one reason why you may hear differences between the digital out of the Apple TV and other devices with optical digital interfaces.

 

[jaddie]

Quote:

You should be aware that the Apple TV only has a 48 kHz clock for its optical out (as well as its internal DAC), so all CD quality audio getting sent through the Apple TV is resampled. This is one reason why you may hear differences between the digital out of the Apple TV and other devices with optical digital interfaces.

Of course the reality is you probably won't hear a difference.  It's up-sampled, not down-sampled, and resampling if done right doesn't damage anything.  
 
(It's just about here that an entire resampling vs audibility of sample rates argument ensues.  Oh well.)  
 
If you want bit-perfect rips of your CDs using Apple Lossless to network around, then grab an Airport Express, that one has an optical out at 44.1, no resampling.  
 
If you'd rather not trust resampling to the lowly Apple TV, you can resample your stuff yourself to 48KHz using any of the many tools available, some are free.  
 
Here's a site that evaluates sample rate converters:
http://src.infinitewave.ca
 
To save you the trouble, anything that uses the Izotope algorithms or Apple Core Audio are about as good as it gets, which is pretty darn good. ffmpeg is decent too.

 

[Audiowood]

^ I am not able to distinguish the following

1) stream apple lossless from ipad via wifi to apple tv3 to wyred dac 2 out to zana duex se using th900.

2) iPod classic wired to wadia I transport to wyred dac2 to zana duex using th900.

Both are volume match and sound quality is about the same. I would fail if I do a Double blind test to tell them apart 100% of the time.I have concluded that Apple TV streaming via wifi is as good as my hard wired iPod with I transport.


Wifi router is the latest AirPort Extreme AC.