This doesn't make sense. Why would an ipod adaptor running off an ipod with music most likely encoded at 128 or 256K sound better than full wave CD's through the CD player? Are you guys sure it isn't just louder? from a technical standpoint it doesn't add up.
+1
I have to agree with the above quote. When I listen to the Ipod hooked in to another system, whether it be vehicle or home system, there is something about it at "first glance" that seems great...but when you really listed to vocals and such, everything seems kind of muddied together vs. a good cd. The best way I can describe it is that its warmer sounding from the CD, individual pieces of the music (vocals, guitars, backgrounds, etc) all seem more defined and easier to pick up. The Ipod is bright, yes, louder possibly due to a "hotter" signal, but its like everything is more run together and harder to pick out. I have a docking unit on my high end Onkyo Integra home system and its the same thing. In my MDX I have a Double Din alpine HU with direct Ipod connection specific for Ipod, and if you compare CD to Ipod on the exact same song, there is so much more depth to the CD than on the Ipod,(the cymbals seem to ring smoother, bass tends to be more deep and rolling, but the Ipod is louder and brighter sounding at same volume level for sure, bass seems "punchier". Granted, there is no arguing the convenience of playlists and so on you get with an Ipod.
I think because the NSX is a tough accoustical environment to begin with, engine and road noise, and for those with a T, listening with roof off, the Ipod is going to give the ellusion of sounding better because of the brightness, hotter signal, and the various EQ functions you can play with on it.
Going with the integrated Ipod connector is probably the simplest way of getting you the perception of better sound, and not change anything, but a CD is clearly the more pure source of "higher definition" sound, you just might not hear it in the NSX. Many people associate a "flatter" sound as been less quality than a brighter/bassier sound. CD's tend to sound a bit flat to me in the NSX , but for whatever reason the source signal from the factory OEM CD changer is very low, which may be seeming like it is a lesser quality source.
As far as audio upgrades, there are so many options that members have done, all of which take it to another level, along with cost.
The ipod integration obviously,
changing door speakers to a component set
external amplification
a true subwoofer
head unit
I have opted for keeping factory OEM headunit, and integrated it into an aftermarket EQ/processer, then to a small and simple amplifier that runs my speakers and a subwoofer. I used a custom built box built by prime member "Angus". All in all, cost was not huge, mostly because I didn't change the headunit, that is probably the most expensive part of a upgrade.
As discussed on many other threads, unless you are looking for audiophile quality, which it appears you are not, don't go too crazy since the NSX is not the ideal vehicle to build and expect high end car sound from...too many other variables.