IPOD Y Cable

kimber
straightwire
http://www.headphone.com/products/cables-and-adaptors/interconnects/straight-wire-musicable-mini-to-rca-1m.php
AP:
http://www.positive-feedback.com/Issue38/analysisplus.htm

Since you're going into a preamp, you should consider a cable that goes from the dock connector of the iPod to your preamp inputs, rather than from the headphone output. That way you're getting a 'line out' signal that hasn't passed through the iPod's internal amplifier.

I don't know if any of the usual high-end cable makers offer one but high-quality versions are available online, like this and this.

I bought a cable from one of those sellers and am very happy with it. The disadvantage of these cables is that you can't run the iPod off external power while it's connected.

If you're using the 1/8" jack, Belkin make a good Y-cable for about $30, which I've found does a fine job.
That said, Sfar is probably right; use a dock & good RCA IC for a better transfer.

I use a 16' cable from Zu. They can provide custom lengths to suit your need. It works great and it is nice to be able to sit in your listening position and be able to select songs without getting up.

Before buying the Wadia iTransport, which run throgh my DAC makes a huge difference, I used a 1M Zu Cable Pivot, which sounded pretty good. About $40 on eBay new.

Neal