What is needed to take out a Raid Boss(lvl50-55)

Well We are a little group consisting of the following party members.
lvl50+ Spellhowler
lvl50+ Prophet
lvl50+ Sorcerer
Lvl50+ Dark Avenger
lvl40+ Shillen Elder.

Is it possible for us to take out a raidbos in our range of lvl(50-55)?.

If yes, whic kind/name should we try out? (eg. one without minions, etc.)

If the above party is to weak, what added classes/lvl are needed to set up a good raid-boss-party?

ive never taken the new bosses but i'd say no
i think you need at least 10 nukers
ill take a guess and say you can do it with 5 nukers who are delvled and have massively overenchanted gear

Well in C3 raidbosses were to be taken on from 3 "normal" groups, incuding melee, ranged and nukes, healers, buffers, whatever. If all raiders are in the same level range as the boss.

I've not yet tried the "new" raidbosses, mostly because we have no idea what it really takes to beat them.

The old ones could also be taken down with less than 20 people, if you use a perfect setup. One tank with healers, buffers, lots of nukers.

Cal

Fewest we took a RB down with on PTS was 7 people.
You need to select your targets carefully though.

A similar group of 12 - 15 people got owned on different RB's of the same level.

5 is cutting it too fine, try to get 2 full parties together

Yep, that's a too few. You need at least one more healer type, and maybe 6 or 7 more nukers to be able to kill a boss. And that's if you have good gear. A BD would help too.

The C4 d-grade level raid bosses are easily doable with one group, even non-ideal groups.

Ummm yeah, with most 50+ raid bosses that group would be eaten instantly. You usually need 2-3 groups. 1 with quite a few healers/MP batteries, a few good tanks (with hate), and a pile of damage dealers. While you may think naaa we can take this, the reality is after you kill all the minions, and start on the boss, you will find before he is dead, and your MP is drained, the minions come back, and usually spoil the show for you. The more DD's you have the better your chances of finishing off the boss quickly.

If you wanted one to try out, I suggest King Tarlk near IT. He is a lvl 50 boss, and as far as I can remember he doesn't have any minions.

1 tank group with tank and healers/rechargers to keep him running.
1 or more full Nuker group with lots of nukers and 1 BD each
and some assorted buffers and rechargers for the nukers. (Think SE or Prophet), bring at least one high level rezzer.