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Discussion Starter · #1 ·
I was given an iPod MMI cable with my new A5 B&O system, and then also picked up a mini-USB MMI cable today. Just had a chance to do some side-by-side listening: I was surprised at how much better the USB-connected hard drive sounded than my iPod 160gb Classic. It is not as big a difference as say Sirius vs iPod, but the music from the hard drive sounded noticeably clearer and tighter. (This is even more surprising given that I had Apple Lossless files on my iPod and was listening to 320kbps MP3s off the hard disk).

It is possible that the B&O DAC is just better than the iPod's (lots of audiophiles complain about the DACs in the iPod Classic). Or, perhaps the B&O system is taking the analog output of the iPod and converting it to digital to run the signal through its DSP before converting back to analog again. This could explain the signal degradation.

Has anyone else tried this experiment?

Other questions on the hard disk front:

1) The manual says it supports MP3, WMA & AAC formats. I can't get it to recognize my AACs. Maybe iTunes doesn't create Low Complexity AACs? Anyone had any luck with AAC?

2) Does anyone know if it supports the lossless WMA format?

3) The 'Mix' function only seems to shuffle the tracks on a given album. Does anyone know how to get it to shuffle the entire contents of the hard disk? (I have my music organized by Genre->Artist->Album->Song).

Thanks,
muski
 

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I was given an iPod MMI cable with my new A5 B&O system, and then also picked up a mini-USB MMI cable today. Just had a chance to do some side-by-side listening: I was surprised at how much better the USB-connected hard drive sounded than my iPod 160gb Classic. It is not as big a difference as say Sirius vs iPod, but the music from the hard drive sounded noticeably clearer and tighter. (This is even more surprising given that I had Apple Lossless files on my iPod and was listening to 320kbps MP3s off the hard disk).

It is possible that the B&O DAC is just better than the iPod's (lots of audiophiles complain about the DACs in the iPod Classic). Or, perhaps the B&O system is taking the analog output of the iPod and converting it to digital to run the signal through its DSP before converting back to analog again. This could explain the signal degradation.

Has anyone else tried this experiment?

Other questions on the hard disk front:

1) The manual says it supports MP3, WMA & AAC formats. I can't get it to recognize my AACs. Maybe iTunes doesn't create Low Complexity AACs? Anyone had any luck with AAC?

2) Does anyone know if it supports the lossless WMA format?

3) The 'Mix' function only seems to shuffle the tracks on a given album. Does anyone know how to get it to shuffle the entire contents of the hard disk? (I have my music organized by Genre->Artist->Album->Song).

Thanks,
muski
It's exactly as you say, the DAC and preamp in the iPOD is not as good as that in the head-unit of your car - something has to give when you package something so small. Mostly, it's designed for the limited dynamic range of a set of in-ear headphones.

Incidentally, when I use the ipod in my band's PA, it makes me cringe how poor this is compared to a CD (yes one of those old-fashioned things!) even with higher bit-rate songs.
 

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Discussion Starter · #4 ·
your AAcs are probably bought from itunes
so they have copy protection on them
Good point, but no, they are converted from FLAC files using Foobar & iTunesEncode, so they wouldn't have DRM. I noticed in the manual that it says they only support Low Complexity AACs -- not sure exactly what this means, but maybe that's the issue. Short of finding a supported lossless format, I would probably opt for 320kbps AACs. I will try some more experiments.
 

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FYI...

Modular encoding

AAC takes a modular approach to encoding. Depending on the complexity of the bitstream to be encoded, the desired performance and the acceptable output, implementers may create profiles to define which of a specific set of tools they want to use for a particular application. The standard offers four default profiles:

Low Complexity (LC) - the simplest and most widely used and supported;

Main Profile (MAIN) - like the LC profile, with the addition of backwards prediction;

Sample-Rate Scalable (SRS), a.k.a. Scalable Sample Rate (MPEG-4 AAC-SSR);

Long Term Prediction (LTP); added in the MPEG-4 standard – an improvement of the MAIN profile using a forward predictor with lower computational complexity.

Depending on the AAC profile and the MP3 encoder, 96 kbit/s AAC can give nearly the same or better perceptual quality as 128 kbit/s MP3.[7]
 
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