HF1 vs HF2

no-one knows yet.... but both will go to ear shattering sound levels.

How about waiting until after CanJam 2009?
Since so far only a couple Head-Fi'ers (Todd, Jude, more?) have had the pleasure to see and hear the HF-2, and they don't give us many hints.

Any Grado will go loud enough without distortion to cause permanent hearing damage, if that's what you're looking for...

The hf1 is more plasticy than the hf2
The hf2 is more unobtainable, for at least the next 9 days
The hf1 will be more unobtainable, starting in 10 days

Indeed..

Like the other guys said, you're going to have to wait until Canjam hits for some impressions, because that people that have heard them won't spill any details

Who's leaking all of that information to you?

To answer the question about loudness: When evaluating a headphone, I'll turn it up as loud as I can tolerate it, and then a little more--but only for very brief periods of time (I value my ears)--just to see if the sound breaks up. What I can tolerate (in terms of amplitude) may be less than most, so I'm probably not your best tester for that. That said, the HF2 played at least as loudly doing that as my HF1.

This is pretty much one of the most ridiculous threads here. You are asking a question about a headphone which has not been released, about an issue that nobody cares about (loudness).

HF-1 has a 1 in the name. HF-2 has a 2. 1+1 = 2 so HF-2 is twice as loud.

I doubt you will be able to tolerate more decibals then either of the phones can produce!

At the very least, HF-1 number 53 will be at CanJam. It's OK with me if people take them over to the HF-2 table for direct comparison.

Nope, in a field with only 2 elements, (HF1)1+0 = 1 and (HF2)1+1 = 0. So HF1 can actually play MUCH louder than the HF2.

I'd recommend a really sensitive IEM for you. It'll block out outside noise, and easily be driven louder than many other cans you'd use. The increase in loudness for ya should be pretty massive. If you damage your hearing though, it's eventually going to be pretty worthless, regardless of how loud something will go.

I've already got the 1 and I have the 2 on order, so I'll compare the two of them. And maybe I'll throw in the MS-1 for good measure.

It's more than double the price and less than double the performance. Yet both give you wood.