Are Headphone amps worth the expense?


I have a Mac tube amp and grado phones. Would I benefit from a headphone amp? How are they hooked up? Thanks for any thoughts.
drpat
Headphone.com(headroom products) Meier-audio headphone amps also use cross talk.
I pondered this very same question a few years ago. I use AKG701's and Ultrasone 8's. I have a McIntosh C2300 (previously a C2200). I used both phones with the built in C2300 with great results.

I bought a Creek headphone amp, and then a Pro-Ject SE. In short and in substance the McIntosh sounded better. More separation of instruments, tighter deeper bass. The add on headphone boxes had a very dry sound in comparison.

Also, I gave up remote control ability. The C2300 has a superb headphone amp built right in and is perhaps under appreciated.

By the way the C2300 has the 1/4" phone plug vs. the 1/8" mini plug on the C2200 requiring downsize adapters (why McIntosh did that was bizarre).
Aren't there special recordings made for headphone listening?

I think they are called binaural and are made with microphones in the ear positions of some kind of artificial head.

Am I mixing this up with something else?
Didn't the Carver Sonic Holocaust try to eliminate the out of phase stuff coming from the other speaker? Didn't Polk make speakers with double mids and tweets which had a wire pair between speakers to remove this out of phase information mechanically, if you will? The double speakers were located about 6" apart, the distance between the ears so the time cues remained.
This is not a new idea.
Good headphone amps are great if you do alot of headphone listening with a good set of phones. Headphone amps (lots of tubed models available, as well as solid state) are hooked up directly to the source component (cd player, dac, fm tuner, phono stage) or can be be placed on a tape loop monitor output on a an intergrated amp or receiver. It is pretty much a preamp and amp, with a headphone jack.

Inless your Mac tubeamp is an intergrated, you cannot connect a headphone amp. They do not get connected to speaker terminals (or headphone input jacks except for ipod like headamps).
There is a headphone jack on my Luxman 509u integrated amp, and my Beyerdynamic T1's sound wonderful when plugged-in. How does it compare to a dedicated headphone amp? I am not sure how much better a high quality dedicated amp would be, but as I am quite satisfied with what I have I am not going to lose any sleep over it.