Two-part headphone question

For the first time in decades, I have an amplifier with a headphone jack. (It's a Creek Audio Destiny Integrated Amplifier.) Two questions:

1) I'd like to give 'phones a try, but I don't want to spend a ton in case I don't end up enjoying the experience. Can folks recommend a decent and relatively inexpensive pair of headphones that a boy might try to check out this whole (forgotten) world of listening with the speakers attached to your head?

2) As the most comfortable seat in the joint is a fair distance from the amp, I'm wondering if one can run a kind of headphone cord extender (quarter-inch female to quarter-inch male) without causeing any problems?

Thanks for any direction you might be able to give me on this one.

Sure you can run an extender, although that will both increase the price of your phones and tend to downgrade the sound slightly, owing to the extra cable and especially the connectors.

As for phones to try out the concept with, sound quality and comfort are the priorities most people mention and the less costly Grados score high for the money in the first category. Some people don't like the way they fit though.

I'm not a great headphone user, but I need them for some things. I have a pair of Grado SR60s and also a pair of Sennheiser 580s. The Sennys are far more comfortable, and better-sounding, but they cost a lot more.
I am a big fan of Ultrasone Phones. I find them to be detailed without being fatigueing. Headphone output impedance should be low 30-100ohm otherwise they can be bright.

I have the Pro 2500 and the I-cans. If you do not need portability the 2500s are great, comfortable and not huge $$$.
The Musical fidelity v2 headphone amp is a steal with a pair of hd 580 or hd 600's . I think its a nice step up for not much more money if any

You could get the awesome v3 for little more.

I also like the Grados too.
You can find AKG 701's for low $200s if that's in your range. Extremely comfortable and I like them much better than the Grados or Sennheisers.
Most phones come with 12 foot cables. You can easily get an extension without a noticeable loss of fidelity.
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HD650 is top line quality. If your headphone amp is not great quality then get something with low impedance. My Sennheiser HD-25-1-11 Pro's work great with crap amps - extremely dynamic and great for PC's or airplane trips as you get around 17 db external noise reduction (cupped headphone design). Horses for courses...these don't sound as good as open headphones and a special dedicated headphone amp though.
I think comfort is the most important aspect for 'phones. If you can't wear them, you are wasting your money. I can't handle the "bowl" style phones. The newer AKG's and higher end grados have them. I like the older grados with radio shack replacement pads. I can wear them for an hour or so.