I'm looking to use headphones through my amp (Roland Cube 40X) and was wondering if anyone could recommend me a good adaptor for a decent price.
I use a jack converter that I brought from Maplins for about £1. Does the job fine, just make sure you have decent headphones.
Pretty much any adapter you get will work just fine, it's more your headphones that will affect the sound. I've got a Cube Street and I have to say, it doesn't sound amazing in headphones, but it does the job.