STUDY: cd vs. ipod in car response w/pink noise

[tcguy85 10+ year member]

i wanted to see if there was a frequency response difference in car between using my ipod and using a cd.

-first i must say, DO NOT pay attention to the actual response, the mic was simply laying in my lap while i was sitting in the drivers seat. but, it doesn't matter since all we are doing is comparing two different sources with each other.

-this test was done with the same pink noise track, one on a cd, the other on the ipod.

-the HU used is a Pioneer 880PRS

-the ipod used is the latest generation Ipod Nano

-the ipod was hooked to the HU with the Pioneer "CD IB100 II" interface

-the EQ in the Ipod was set to flat. and yes, it does matter, even when using the dock port. i quickly picked a different EQ setting in the Ipod and the results did change.

i must say i am a little shocked at the results, but they don't lie. you'll see the only difference is a measly 1.4db difference at 80hz. i honestly don't even remember which line is for the Ipod and which is for the CD, but obviously it makes no difference.

so if you are hearing a difference between the same music on a cd and the ipod it is not the Ipods fault(unless you have the EQ on anything but flat).

Click to read more...

 

[tez4life Premium Member]

Interesting result TC, honestly not what I was expecting.

 

[tcguy85 10+ year member]

***i also just realized that on the EQ on the Ipod source on my 880's EQ i had 80hz cut one step. so that explains the slight difference at 80hz.

soooo, that means it's exactly the same!!

 

[tcguy85 10+ year member]

Interesting result TC, honestly not what I was expecting.

yea, me either. i could have sworn i was hearing slightly less on the tippy top end when using the Ipod. but i guess it's either psychoacoustics or the mp3's themselves.

 

[Supergumby5000 5,000+ posts]

interesting

 

[shaneb 10+ year member]

interesting...but, CD quality tracks (i'm not talking about burned cd's) i have heard, are better quality than mp3 format....

of course i have never attempted to prove this.

 

[tcguy85 10+ year member]

i'm not proving that they won't sound different either. don't think i don't know that. i am just proving that the response is the same on paper.

 

[shaneb 10+ year member]

i'm not proving that they won't sound different either. don't think i don't know that. i am just proving that the response is the same on paper.

RIght on, wasn't trying to argue..I should have phrased that - "Hey do a test on a real cd track compared to a downloaded mp3 of the same track, I heard it would be different" //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[tcguy85 10+ year member]

RIght on, wasn't trying to argue..I should have phrased that - "Hey do a test on a real cd track compared to a downloaded mp3 of the same track, I heard it would be different" //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

it's all cool. i didn't think that you were. i just wanted to make it perfectly clear before i get flamed for people thinking i can't hear the difference between an mp3 and the original.

what i wanted to test is the ipods frequency response along with pioneer's ipod interface. i figured there would be a difference.

i am in no way shape or form trying to say an MP3 on an ipod will sound the same as a cd. i'm just saying that the frequency response of the ipod and the pioneer interface is dead flat, which is sorta shocking IMO.

so kudos to apple and pioneer.

 

[shaneb 10+ year member]

it's all cool. i didn't think that you were. i just wanted to make it perfectly clear before i get flamed for people thinking i can't hear the difference between an mp3 and the original.
what i wanted to test is the ipods frequency response along with pioneer's ipod interface. i figured there would be a difference.

i am in no way shape or form trying to say an MP3 on an ipod will sound the same as a cd. i'm just saying that the frequency response of the ipod and the pioneer interface is dead flat, which is sorta shocking IMO.

so kudos to apple and pioneer.

Yeah, i'm impressed.

Anyway, while your at it, i am curious of the difference between original and mp3 copy //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[alex5857 10+ year member]

as long as the song is 256kbs or higher i do not notice the difference

 

[tcguy85 10+ year member]

Yeah, i'm impressed.Anyway, while your at it, i am curious of the difference between original and mp3 copy //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

the original pink noise track and the mp3 pink noise track?

the difference wouldn't be enough (if any) to matter in this test, obviously. there is a thread somewhere on this forum(i think in the HU section) that discusses the difference and has all kinds of helpful graphs and pictures.

 

[tcguy85 10+ year member]

as long as the song is 256kbs or higher i do not notice the difference

until you get into REALLY low bitrates you won't see (or hear, i should say) a difference on a pink noise track. but, once you get into really really low bitrates the very top end and very bottom end will get chopped off.