View Full Version : USB vs. cd SQ

08-31-2007, 12:36 AM
Hi, I was wondering if anyone has used a head unit with a usb input to play an ipod, and how the sound quality differs between that and a cd. I have an aux input on my head, and i know that there's a difference between the aux and cd, but is there a difference between usb and cd? Assuming that you're playing the same audio file, an mp3 on the ipod, and that same mp3 burned onto a cd.

Thanks in advance

08-31-2007, 03:59 AM
Should be the same, since they're both using the mp3 decoder and DAC built into the HU. Now if you were talking about mp3 from ipod vs an actual store-bought CD, well that would be different.

08-31-2007, 05:31 AM
Technically since its the same data on two different media, it should sound the same. I agree with Kross, if it was Song A recorded in mp3 on Ipod versus same Song A from retail CD, then yeah, retail CD would be better.

Side Show
08-31-2007, 05:55 AM
yeah cd everyday....... mp3 = ****

09-01-2007, 01:32 AM
Thanks for the info.
Has anyone used a head with a USB input before, i'd be very interested to see how it compares to cd. Thanks

09-01-2007, 01:36 AM
My 6900 has USB. I use an ipod, which sounds good but if you want all out SQ cds are way better.

09-01-2007, 03:40 AM
Look at what formats the particular hu supports. There are a lot better formats than mp3. If the hu you are looking at supports formats other than mp3 then you should be able to rip music in the higher quality formats onto a thumb drive and plug it in. If you are planning on using an ipod, make sure you turn off all eq's and enhancers on the ipod and record your songs at a higher bit rate. This will give you better sound.

09-01-2007, 03:45 AM
I use my USB flash drive on my pioneer 6900, and i rip everything at 256 kbps. and all in all CDS ARE BETTER IMO.

09-01-2007, 03:58 AM

The thumb drive/USB should be better than the MP3 CD...

There are always errors when reading/writing an optical format.

Not that you are going to be able to tell the difference... ;)

09-01-2007, 04:27 PM
Good point. My CD's in my car are always getting scratched up. :pissed:

09-02-2007, 12:26 AM
USB can be better quality then cds, the thing that makes the quality is the quality of the recording. Altought usb can be > cs usually isnt

This is why i sold my IVA-w200 cus i didnt wnaa use my ipod any more i wanted to play just cds and that deck + ipod was **** quality...

09-02-2007, 12:42 AM
Well, by no means did I mean that USB MP3 data would equal a Red Book CD.

In a car unless you can play SACD or DVD-A a Red Book (standard) Audio CD is about the best you can get.

Unless you are using a lossless format on your USB Data Adapter...

09-02-2007, 02:10 AM
Does a USB connection have much better SQ than an aux input, or is there a small difference between the two?

09-02-2007, 02:47 AM
I don't think it really matters. I think the most important thing will be the source. Using a thumb drive or a Line-out (instead of headphone jack) from your mp3 player, will ensure that the hu is playing the data purely. Using the headphone jack on an mp3 player will send the audio signal mixed with any eq or other audio adjustments that you have set on the mp3. So if you go this route make sure you turn all of those setting off.

09-02-2007, 01:42 PM
One thing about sq has to do with the d/a converters. When using an ipod you are using the cheap d/a converter in the ipod not the better converter in the head unit. A cd with mp3s on it should sound better then an ipod because its using the head units d/a converter. Only HU that I know that has a digital input from an ipod is the Alpine iDA-X001.