I'm confused on 2.5 vs 3.5 mm cable.

iPods don't support balanced cables. The four pole 3.5mm jack supports a common ground, left and right audio output signals and a mic input.

tt2

The balancing bit happens in the audio hardware not the cable that links things together. That needs enough conductors and contacts to support the task. You cannot use two pole jacks and two core cable to transmit a balanced signal, but with three pole jacks and two-core cable with a screen you can pass either one balanced signal or two unbalanced.

tt2

Again, it isn't the cable, it is the equipment that is, or is not balanced. Yes.

tt2

TRS 3.5 and TRRS 3.5 should both work. It won't matter if an unsupported mic is connected to the iPod. Models that do support mic input via the extra ring should also play audio to standard headphones using a TRS 3.5 connector without a problem.

tt2

I’m am also utopia the difference between the two I keep have my original cord replaced with a bigger longer cable the original usually will not charge my phone.

You're welcome. 🙂

tt2

The 5th generation iPod classic has a 3.5mm stereo jack socket. I can't actually recall if that version includes support for voice recording or if that came in with the next model, but you cannot use a 2.5mm connector because it would fall out. If you're describing the overall thickness of the cable rather than the connector then 3.5mm is going to be more durable.

tt2