cccplus

go with the ipod adapter. the sounds from the ipod are much better than fm and would depend on how the mp3 is burned for cd quality. i can tell a difference between fm and ipod even when i'm not an audiophile

on a different note, i heard bmw came out with a cd changer that can play mp3 cd. is this correct?

BigAardvaark

If set up and used as per my earlier post (iPod in disc mode with just the standard white Apple cable or a USB drive), with decent high bit-rate or lossless encoding, the USB interface IS CD quality unless you're the owner of incredibly discerning hearing. Even then, unless you have the L7 or better audio you probably won't hear a difference as soon as you start the engine anyway!

iversonm

I doubt they would even be able to discern the difference then, either. As you mention, road and engine noise pretty much defeat any attempts at fidelity. I have a few poorly-encoded MP3s that sound marginal through headphones or on the home stereo, but sound fine in the car.

As you mentioned, at any decent bit rate, you'll need a carefully controlled experiment to tell the difference. On top of that,
the vast majority of people's hearing sensitivity falls off quickly around 18kHz. (Mine certainly does, and it is classified as normal.) The audio compression algorithms exploit this phenomenon by eliminating signal that is marginally audible.

Talk about 20Hz-20kHz fidelity usually brings sniggers from my audiologist wife.

BigAardvaark

This is true. So I threw watts and a bit of Alpine technology at it, worked a blimming treat! In the UK, it's rare we exceed about 15mph so it sounds great 99% of the time. It sounds so nice in fact, it really makes a fantastic job of showing what a complete mastering disaster modern CD's have become. Somebody mentioned FM station compression earlier, most new CD's are the same, overly compressed crap in some kind of runnerless race to make them sound the loudest.

As for the <20khz thing goes, here in the UK we use the fact that teenagers can hear a much higher freq range than "grown ups" by putting "mosquito" devices in areas where we'd much rather they didn't congregate. Basically very high pitched buzzers that only scrotes can hear.

Anyway, miles off topic so, don't hesitate, GET THE USB INTERFACE, it's marvellous.

kirk

Aha! don't forget that the usb port can read USB keys directly! so if the upgrade is usb+autio-in you can play music straight from usb keys OR from an iPOD (with the overpriced cable).

BigAardvaark

Just put the iPod in disc mode and use the white apple cable instead of the overpriced cable.