I've tried to play my iPod through my stereo, and it always sounded like total crap. Too loud, scratchy, and it sounded like it was muffled by a few feet of cardboard. Line in, headphone jack, no difference. (But the headphone jack sounded about 5% less crappy.)
This patch cord used to work perfectly with a CD player, but it's been a long time since I used it. The iPod works fine, so I started to suspect a bad cord. Just for kicks, I used another cord (going into another input), and it sounded wonderful. Using the bad connection on the XM tuner make it sound like crap, too. Progress!
Just for kicks, I switched inputs, and identified the problem: the phono input. Switching the patch cord to another open input fixed everything. Who'd'a thunk it?
Now for the $64 question. Is the phono input specially calibrated to receive input from a turntable (doubtful), or do I just have a bad set of inputs (probable)?
In other news, Slim Devices upgraded their SliMP3 and came up with the Squeezebox. The SliMP3 was a cute idea -- a networked stereo component that played streaming MP3s from a server somewhere in the house, but it was wired. The Squeezebox fixes this design flaw -- it can receive streams over wired ethernet or WiFi.
Re:phono is input for turntables ...
bart on 2003-11-20T12:46:29
That URL gives me an error ("Redirection limit for this URL exceeded").But anyway: phono is indeed only for turntables. Why? Because it contains a special preamp, turning the phono signal into a normal audio signal.
- A turntable element reurns a very feeble signal: a few mV typically — roughly the level of a microphone. Normal audio jacks expect a signal of 100mV to 500mV, approximately, which is what normal audio equipment, tuner, cassette tape player, CD, deliver. So the preamp needs to boost the signal by about a factor of 50-100. That's a lot. Any other input, like from the iPod, will most likely be much too too strong for this input, resulting in a heavily distorted signal.
- Phono signals require a special equalization: bass needs an extra boost, higher tones need to be weakened. This correction is known as the "RIAA correction". You can see a nice graph here, under point 3, showing both a theoretical approximation (straight lines), and the practical EQ (curve). So even a good microphone, when connected through the phono input, would sound like crap, because of this.
I found a rather nice explanation here (subsection "Phono Pre-amplifiers").
