3.5mm jack or USB for better sound?

[jrm]

my HU has both options. Using a 80g ipod classic or a iphone 4.

 

[Gerdo]

The USB will be slightly better and it will charge the ipod.
Either will work just fine. In a vehicle, I doubt you would hear any difference.

 

[GX4SEVEND]

On my old runner I ran my iPhone at the time off the USB with an alpine deck. When I sold it and got a 335i with logic 7 sound I used the 3.5mm. I thought there was a world of difference in sound. Plus you couldn't charge it. Plus I couldn't control it from the deck and the phone screen dims less then half way through a song.

If it was me and had either option I would do USB for sure. Just my $.02

 

[RAD4Runner]

The USB will be slightly better and it will charge the ipod. Either will work just fine.

Agree.
When using 3.5 mm plug, your media player audio processor produces the audio. HU will simply amplify.
When using USB, HU audio processor will produce the audio. Chances are HU audio processor will be better than media player or iPhone audio processor, because that is the former's forte. Therefore, theoretically, USB would be better.

In a vehicle, I doubt you would hear any difference.

Yep, Realistically, there's too much noise in a vehicle that human ear will probably will not notice the difference.

 

[RAD4Runner]

On my old runner I ran my iPhone at the time off the USB with an alpine deck. When I sold it and got a 335i with logic 7 sound I used the 3.5mm. I thought there was a world of difference in sound.

Was 4Runner better than on 335i, or the other way around?

 

[GX4SEVEND]

Lol probably should have clarified that. Using the 3.5mm vs USB I'd say the runner was better because of the USB. Now cd for cd the 335i had a much nicer sound system even though it was stock.

 

[Offroader5]

One thing I noticed is that sometimes (not sure why) when I use the 3.5mm to connect my phone to the HU, it adds noise. Noise as in buzzing with the rev of the engine. A ground loop or something...not sure, doesn't do it all the time. USB is clear as day.

 

[RAD4Runner]

3.5mm is analog, noise picked up will be amplified.

One thing I noticed is that sometimes (not sure why) when I use the 3.5mm to connect my phone to the HU, it adds noise. Noise as in buzzing with the rev of the engine. A ground loop or something...not sure, doesn't do it all the time. USB is clear as day.

As expected, because when using 3.5mm plug, HU amplifies all analog signal from aux input cable, including interference picked up from ignition. (Also see my post above)
On the other hand, when using USB, HU will filter out analog noise picked up by USB signal, and process only digital mp3/mpa data, that's what digital signal is about- clear as day

Regards,
RAD