Earphones driven by preamp RCAs?

I have plenty of volume at 12:00 - that is not the really what I am interested in here.

What about the quality of the sound? What if I compare my headphones on the pre, to my headphones on a headphone amp RCA, to my headphones on a pre with a headphone jack? Sure, the answer will depend on the specific units compared, but how do they compare in general? What are the pros and cons? If I wanted to get the best sound, which direction would I go? Or are all three just as capable?

If I already own a fantastic pre (RCA out only), would there by any reason to add a headphone amp?

Thanks

1. In general, a well constructed purpose-designed device, like a headphone amp, will be superior, for driving headphones. Note, they have a much lower input impedance than that of the average amp. Of course, such a general statement is irrelevant when you get to real-world specifics.

2. Just because it's loud enough does not mean that it has enough power to work into that load without distortion. A 12 o'clock setting is pretty high (in general and without knowledge of your preamp or the gain curve of the pot). Is that where you set it to feed the amp/speakers?

3. Why not just try a decent headphone amp and see for yourself if it is better? Surely, there are web dealers with a useful return policy.

Kr4: For the same volume, the speakers are at 9:00.

Lets get more specific. My pre is an ARC LS 25 MKII. Can I do better with a headphone amp?

Hard to answer as I've never used one. However, ARs tube units have more than decent line driving.

My advice stands: Try a good headphone amp.