Digital music questions

There are no third-party integrations with Apple Music so if you go the separate streamer route, you’ll need to use AirPlay which is stuck at 24 bit / 48 kHz max for AirPlay 2.

You can play back high-res files from Apple Music on your Mac. You just need to enable it from the Music app. Go to Preferences -> Playback and then select the highest resolution from the ’Streaming’ and ’Download’ dropdowns.

You’re on the right track as far as audio quality and streamers go. They’re all 1’s and 0’s. As long as the data is getting to your McIntosh DAC intact, then one streamer is no better than another in terms of audio quality.

There can be wide variations in terms of ease of use, features and technical support so I encourage you to make your choice based on those criteria rather than on anecdotes on sound quality.

A streamer is basically a computer with some specially configured audio software. For example, I’ve made my Mac mini into a streamer using a free app called Kodi. I also have a Raspberry Pi based streamer running moOde for my basement system. I’ve got a fairly technical background so I went the DIY route. You might view the Mac as a temporary situation or are less technically inclined which nudges you towards a turnkey solution.

@soix 

Noise and clock quality are basically immaterial when you're using the USB interface as the transport. This is an asynchronous mechanism - the receiver (i.e. the DAC) will buffer and clock out the data.

Also, I'm not sure why having a technical background is frowned upon. All of these concepts and components were created and advanced by scientists and engineers. In short, audio reproduction wouldn't exist without science.

@thyname 

I'm not part of the 'ASR contingent' as you call it but I do like to see and use evidence (whether it's from measurements or valid listening tests) to make more informed choices when it comes to spending my money. I guess you have a different system.

@thyname 

Statements which I made in my first post can be taken seriously because that is how digital data works. If the data received by the DAC's USB receiver from two different components is the same - whether it was sent by a $100 streamer or a $10k streamer -  then there's no difference between the two components. It is literally the same audio signal that's being communicated. This is fundamental to how digital systems function. The OP understood this concept and made a rational conclusion from that and I basically confirmed it.

In any case, this aspect of performance can (and has been) tested before. See this post in Audiophile Style. You can test your digital interfaces for yourself if you want to download the program (available here). This blog post is also a good reference on what errors in digital audio transmission sound like.

@soix

Let’s first deconstruct your argument re: noise and clocking (jitter).

If the streamer receives audio data over the network, noise and jitter can cause bit errors. However, networking protocols such as Ethernet and TCP/IP contain methods to detect errors and ask for packet or frame retransmission. You can be assured that audio data isn’t being mangled when it arrives over the network. For example, my Windows PC has received ~479 million bytes since I turned it on this morning. Exactly zero frames have been discarded due to detected errors. You can do this yourself by typing in the command ’netstat -e’ in the Windows command prompt. My Raspberry Pi 4 based streamer running moOde has received over 6 GB of data via Ethernet and also zero errors detected.

Let’s say that audio data is stored locally on the streamer. In this case, noise and jitter can cause bit errors when transmitting to the DAC. These types of errors will manifest themselves as audible clicks, pops or even dropouts (if the USB interface at the DAC detects errors or loses connection). This was also covered by the link to the testing that I referenced in my previous reply. To sum that up, after 12 hours of continuous playback using USB, no errors were detected.

Finally, there can be noise injected into the analog output circuitry. However, this is only a problem if you can hear it at the playback volumes you usually listen to. For example, I can hear noise with my Benchmark HPA4 / DAC3 B system on my AKG K371 headphones but only if I crank the volume to max - a level that I would never listen at. If I do the same thing on my DAC3 HGC connected to my PC and turn the volume all the way up, I only hear silence.

Now onto streamers, yes I’m saying that an inexpensive streamer can sound just as good as an expensive streamer if the DAC receives the same data. Bits truly are bits - and that’s the beauty of digital data. We can make and store and stream as many copies of music files as we want and as long as those copies match the original bit for bit, they will always sound identical. This is why you see encryption being used on non-paid music downloads from services like Apple Music or Qobuz.

@jetter 

Thanks - I appreciate the comment.

@ghdprentice 

I can accept the fact that people hear differences when using different streamers in their setup. However, in most (if not virtually all) these cases, I don't think it's the streamer that's causing the difference. Since it's difficult to know how controlled the conditions were for these evaluations, it's hard to judge how reliable the outcome is given that people can be easily swayed by our own biases and other external factors. This video sums it up nicely - https://www.youtube.com/watch?v=_nthIOIXizs

@femoore12 @cmb13 

If you're connecting the Macbook via USB to the McIntosh, then the McIntosh is decoding the audio data. What's happening is unfortunately it seems the Apple Music app isn't switching the sampling rate automatically. You can switch it manually using the 'Audio MIDI Setup' utility if you know what the actual sample rate is. Otherwise, macOS is resampling the music to match whatever is set in 'Audio MIDI Setup'. I don't know why Apple can't quite get their act together on this but it is what it is.

There are players out there that will switch the sampling rate automatically. For example, Kodi can do this when the 'Output configuration' setting in System -> Audio is set to 'Best Match'. However none of these players are integrated with Apple Music streaming.