Let me repeat that: 24/48 sounds worse on the iPhone than 16/44.1. If you convert to 16/44.1 (CD quality) ALAC (apple lossless) then at least the headunit (assuming you have a highend headunit) will do the decoding on board and you will acheive the best sound you can hope for in a car. When you play these tracks back in your car your are forcing the iPhone to do the decoding which actually gives you worse sound than the headunit doing the decoding. A lot of headunit manufacturers out there claim to use 24bit DACs (Alpine comes to mind) but none of them will actually decode 24bit audio tracks. You mentioned you were listening in your car. It doesn't matter anyway because without an analog out on crap hardware like a cellphone you couldn't achieve CD quality audio in the best environment. The DAC (digital audio converter) built into the iPhone doesn't 24/48 output in analog. The iPhone will playback those files but not at that quality. The issue I take with everything you've posted is that you're trying to use your iPhone for playback. Sample rate arguably makes less of a difference in perceived quality. That's what you get when you go from 16bit to 24bit. There is potential for a large dynamic range with a greater bit depth. I know this thread is old but I stumbled upon it and I thought I would throw in my opinion on the subject.

So, I hope this info helps anyone else who is trying to convert big HD music files for use on an idevice, and thanks to everyone for chiming in. Don't fully understand it all yet, but the sound is my answer for now. Whatever this converter is doing, it really works.Īnd, I really think bit depth is important, just like on our computers. I've been CRANKING Talking Heads Remain In Light, and it's blowing me away. I always thought it was my amp or speakers. The thing that really got my attention was that I was not wincing when the dynamics got intense, as CD's always seem to clip or distort when the going gets rough, or if the sound is dense (lots going on). The net result is sound, even in my car, that sounds far more rich and with clarity of detail that I've never heard on a CD. No, I didn't try AIFF, but the converter I used - MediaHuman Audio Converter, is running at 2300kbps, according to itunes, and in 24 bit, and I was able to keep it in ALAC. I jus tknow there are people with audiophile libraries who must be doing this regularly. i'm not a music snob, mp3's actually kind of hurt my ears, kinda like aural sunburn. I just can't believe there isn't a simple converter that won't do more than just evicerate the data and leave me with essentially the same shyte I could buy from itunes. I know they would be big files, that's fine. So, my original question was about whether there was a way, either native in itunes, or with an app, that I could simply convert these files down to rates supported by the phone (24/48, optimally). The phone will actually support 24bit/48k, which is a really big jump even from CD, and a giganti one from 320 AAC or mp3. Itunes supports these files, they play fine, and I have my MIDI output set to its max, which is 24bit/96k. I've got music that's 24 bit, 96k, with bitrates at about 3000 in ALAC (50k original). And this is just CD quality, 16 bit/ 41.1k sampling rate. The thing is, I can really hear the difference between 320 and CD, which is usually around 700-900 with ALAC for me. Thanks, Chris - got it about the AAC, since the bitrate limit seems to be 320, I just lumped it in with mp3 (still learning about all this).

Download MediaHuman's Audio Converter