Sounds like you would enjoy the Telefunken tubes... they are the quickest sounding tubes to my ears. The NOS Telefunkens are expensive, but JJ is currently making rebranded tubes which are supposed to be decent. I would imagine that they do not compare with the original Telefunkens, but it's worth a shot.
To give you an idea on cost, here are some links...
Original Telefunken tubes - very fast, quick decay, "solid state" sounding, with a very natural sounding tube infused sound... not particularly warm or bloomy... good for faster genres like metal/jazz:
(Note the getter and the support, with the dimple in the middle and the angle on it. Also note the number code vertically on the side, and the gold pins. Also note the dual supported stage, beneath the getter, and the shape of the grid. The ones made in Ulm, Germany have a diamond imprinted on the bottom... these are the most sought after).
(Another auction with good pictures, note how everything checks out as per above)
Here are the new production tubes, made by JJ in Chekoslovakia. The black label ones are apparently hand selected.
I would also recommend a Russian tube; the Voskhod rocket style actually does quite well with faster genres, such as metal. Instead of buying off eBay, you may want to contact @rb2013 as he has a selection of tested tubes. He is also a great resource for 6DJ8 tubes, as he put up a fairly comprehensive review. He rates the Russian tubes as #1... I do not. He has a lot of believers in the tubes, and I personally found they worked best for fast genres, myself. The Russian tubes are a crapshoot on eBay, and I would strongly urge to consult rb. They are also fairly cheap, although he probably sells the most highly rated ones for more. I haven't heard any of his "holy grail" rated tubes, so I can't comment on them.
PS. The model numbers and price of headphones doesn't dictate quality... (eg. the Beyer DT-880's imo are much better sounding headphones than some of their newer models.) Just food for thought. Price does not always equal listening pleasure.
Appreciate the links and the information. I will get in touch with RB2013, was reading through his reviews, makes it much harder to decide now.
Though i will probably get a telefunken (either ones from the ebay or the new ones )...
I own the HD700 and the Aune T1 mk1. Besides the stock tube, the only other tubes that I have are all of the Amperex Orange Globe 6DJ8 kind.
Some quick impressions of the Aune T1 with Orange Globe tubes and the HD700 combo:
Vocals are definitely pronounced - but they aren't extremely in your face. Guitars come through cleanly and distinctly in rock music (I listened to some Eagles and Aerosmith to test this out), though I wouldn't say they are at the forefront of the music. The HD700 definitely is not clinical here - this combo gives it a bit of warmth that works well with most genres of music. Actually, I really like this combo because the Orange Globe tubes seem to tame the treble of the HD700 a bit (which is good for the HD700, but to me is a bit annoying with other headphones). The only complaint that I have is that the Orange Globe tubes don't seem to provide as much bass in comparison to other tubes (like the stock one) - but I'm not sure how important that is in rock music.
In case if you're interested, here's a couple of listings on eBay that I found for the Orange Globes:
In my experience, you should be fine buying used tubes, especially if the seller has good ratings and/or provides information how the used tubes have tested on some kind of machine. I actually bought a set of four used Orange Globes like the second listing, and the tubes are still going strong more than a year I bought them.
*EDIT: Actually, I don't want to sound like I'm shamelessly promoting myself, but if you want, I can sell you some of my other Orange Globe tubes for cheap. Just PM me. But if you really are in Europe, I probably can't sell it to you because shipping costs would probably be higher than what I'd sell you the tubes for since I'm in the US.
@chowmien83 Thanks for the links and you've got a pm.. since i do have an option for you to ship the tubes to the states, just in case you are willing to sell it .
I cant wait to get my hands on the HD700's and start listening on them...