Having put some time and money into my car audio, anyone who listens to it can notice the amazing sound quality or variations thereof from different sources (CD, HD radio, AUX, USB, lossy, lossless, etc) without being an audiophile. Right now, it sounds incredible when streaming AM on iPhone 6s with Cellular Data > High Quality Streaming over AT&T's network. I'm grandfathered into the unlimited plan, so I stream 'till my heart's content.
I was curious about two things, however: how much data was I actually using streaming, and whether HQ streaming and downloaded content sounded differently. Here are some rough numbers based on some quick tests I did using the DataMan stopwatch (not an exact science but relatively accurate from my experience):
HQ Streaming over AT&T LTE:
- 10 min = 4MB data used
- 1 hr = 25MB (extrapolated)
- 40 hr = 1GB (extrapolated)
Downloaded (same size whether over AT&T LTE or wifi)
- 5 min song = 10MB actual file size
- 10 min song = 20MB actual file size
- 1 hr album = 120MB (extrapolated)
In my car, there is a notable audible difference between a song streaming in HQ vs. its downloaded counterpart. Again, one doesn't need to be an audiophile to hear less separation, less breadth, depth and a smaller soundstage in the downloaded song. This—combined with the small file sizes of the downloaded songs—leads to me to believe that downloaded content on AM is of lesser quality than its 256k+ AAC streaming counterpart. There isn't as noticeable of a difference when using my mid-grade Sony earbuds, though.
I cannot listen to downloaded AM music in my car because I know I have a better sounding option available to me. This is disappointing as there are/will be times when I may not have cellular coverage and/or I'm being throttled for exceeding my 22GB (hasn't happened yet). So, I need Apple to allow us the option to choose HQ quality downloads.
And they still need to work on that hideous UI.