Dynaudio - iPod VS CD

[Mariani]

Has anyone else noticed that the Dynaudio sound quality is MUCH BETTER playing a CD instead of using an iPod via MDI?

The MDI applies some sort of weird compression and changes the sound quality. CD is raw and plays it the way it was intended. Disappointing really, coming out of a mini with AUX Mini jack I was really looking forward to USB iPod.

What is the best way of loading this exact raw quality on the internal hard drive? Is it possible?

Mic

[Drift]

The MDI doesn't compress anything. It's working with what it's given 128kbps is 128kbps no matter which way you spin it and if you allow iTunes to do it's thing, when updating your library, that's what you'll get.

The integration with iDevices isn't smooth enough for my liking (I'm fussy though) so instead I use a 16GB thumbdrive loaded up with a mix of WMAs & MP3s with a minimum of 196kbps. More than happy with the sound quality and certainly indecernable from CD.

[straight_fresh]

if you use apple lossless when loading songs on your ipod it doesnt compress them at all, goes straight onto your ipod the way it was on the cd, you do sacrafice storage space though, my 8gb itouch only has 300 or so songs and its full

[118 Tsi]

Even with normal sound system and aftermarket options it's the same deal. Regardless of the Kbps of the mp3, it's just ****ty! Should really be perfect quality!

[Corey_R]

I'ved moved this to the VW Audio and Electronics forum as this is not MK6 specific.
Also, it wouldn't surprise me at all if the iPhones MDI output is analogue, as almost all iPod audio connections are analogue.

In my experience, there is no difference between "real" USB devices and CD given appropriate audio files. The issue you are experiencing is something you need to live with due to Apple's product design.

[Mariani]

Corey, I think you may be right. This is the design of Apple's IPod. Nothing to do with the file quality. I did the test. Purchased a new album from iTunes. Played It through iPod via MDI and then burnt to CD as an audio file. CD is 10 times better. No question about it.

I'm going to try and import data files into the hard drive and do another comparison.

Apologies about thread category.

Mic

[AdamD]

As Corey says, the dock output for all iPods and iPhones is analogue - you're using the tiny DACs in the device to do the conversion. (This is why not all Apple products are created equal in this respect - many are better than others in terms of DAC specification and quality.) Apple have done this for copyright protection reasons: remember they used to sell DRM music; output of a decrypted digital bitstream would allow anyone to circumvent it and copy the music.

[halojump]

CD Audio will in most cases always be better than MP3 (or whatever digital format you like) as there is a loss induced in the production of the audio file. This is regardless of what brand of Digital Audio player you have. The analogue connection from the iPod (which I wasn't aware of) will just make things worse.

All that said, your'e in a car, with road noise etc. You'll never really get 'pure' sound. Plus it's way better than my first car, a 1987 Corolla with an AM only push button radio.

Not that I am an audiophile or anything - check out the article @ MP3 vs AAC vs FLAC vs CD | Stereophile.com and MP3 vs. CD Audio Quality Tests

[PunkJr]

The MP3 format takes a song in CD format, then throws away 4/5ths of the information! It then guesses as to what it should put back in playback. Comparing MP3's to CD's is like comparing VHS video tape to DVD. By playing the song from your iPod, you are using the DAC from the iPod rather than the DAC in the head unit. To put it into perspective, I have a standalone DAC on my hifi at home that cost $700 (you can spend a lot more). The DAC in your iPod is worth about $2. The DAC in your head unit would be substantially better than the one in your iPod.

So you have two issues here that are contributing to horrible sounding music, and if you're listening to hip hop or pop, then there is a third issue also.

[Mariani]

Ok...

After running various tests I can confidently confirm the following:

Playing music through the internal hard drive is WAY BETTER quality than playing it through your iPod via MDI

There is none of that dodgy compression, the bass is clearer and actually kicks nice and strong.

I'm now grabbing all my favourite albums and loading them onto the HD.

Mic

[sillywet]

As Corey says, the dock output for all iPods and iPhones is analogue - you're using the tiny DACs in the device to do the conversion. (This is why not all Apple products are created equal in this respect - many are better than others in terms of DAC specification and quality.) Apple have done this for copyright protection reasons: remember they used to sell DRM music; output of a decrypted digital bitstream would allow anyone to circumvent it and copy the music.

I understand the technical reasons why CD should be better than an iPod, but in the case of the VW it's especially bad. If you play audio through bluetooth, sound quality (as long as the file is decent) is just as good as a CD to my ears. If you play the same song with the iPhone plugged in to the MDI, you almost completely lose the bass, and it seems to want to play the vocals through the tweeter on the driver side only. Makes no sense whatsoever. And to defend the iPhone, my Denon receiver at home allows me to plug the iPhone in using a normal Apple charger cable (ie essentially the same as MDI), and audio quality there is for all intents and purposes CD quality. So unfortunately I think the bulk of the blame should be levied upon VW rather than Apple in this case.

And this is exactly why i'm trying to figure out if I can make my RCD510 allow me to change songs with bluetooth audio using the screen or steering wheel such as with the RNS510.

[AdamD]

So unfortunately I think the bulk of the blame should be levied upon VW rather than Apple in this case.

I use a dedicated iPod Classic via MDI to my RNS-510 w/ Dynaudio every time I get in my Golf. And I think that considering the tech, it sounds great, and very nearly CD quality at most frequencies. (I tend to listen to mp3s encoded at the maximum 320kb/s bitrate using good encoders if possible.) I do consider myself something of an enthusiast (if not quite an audiophile) when it comes to music and hi-fi - I do know good audio.

Sounds to me like something in your MDI is not right. Have you got the input level set to the correct value (LOW)? Are you running the latest MDI firmware?

[aussietig]

I use a dedicated iPod Classic via MDI to my RNS-510 w/ Dynaudio every time I get in my Golf. And I think that considering the tech, it sounds great, and very nearly CD quality at most frequencies. (I tend to listen to mp3s encoded at the maximum 320kb/s bitrate using good encoders if possible.) I do consider myself something of an enthusiast (if not quite an audiophile) when it comes to music and hi-fi - I do know good audio.

Sounds to me like something in your MDI is not right. Have you got the input level set to the correct value (LOW)? Are you running the latest MDI firmware?

Yep ... I second that!

Nothing beats the convenience of updating songs in your car by just syncing your iPod to iTunes and reconnecting to your MDI.

Sounds just as good @ 320 bitrate.

But biggest advantage with connecting an iPod is that it will play WAV files, whereas the RNS510 doesn't recognise them.

[sillywet]

They told me I can't do a firmware update to my RCD so sadly i'm not sure if this is the issue. Will check the input level tonight, but I haven't changed anything.

Perhaps I should have just got the Dynaudio option. I only ever listened to music via bluetooth in the dealership which made the stock system sound epic. This is still how i play my music as the quality is CD quality, just shats me that I can't control the songs via steering wheel/screen. Oh well, I guess i didn't buy the car for its ability to scrool through music, so i should really just neck-up.

[AdamD]

They told me I can't do a firmware update to my RCD so sadly i'm not sure if this is the issue. Will check the input level tonight, but I haven't changed anything.

The firmware is for the MDI, not your RCD-510 head unit:

MDI | my-gti.com

And the most frequent cause of poor quality audio from the MDI is when the input level is set to Mid or High (especially if using an iPod/iPhone). There's no guarantee it's set to Low by default when you picked up the car - it's been on another setting for many others.

Oh well, I guess i didn't buy the car for its ability to scrool through music, so i should really just neck-up

Mate, don't settle - that's what the forums are here for, to help you solve problems.