The amp looks like a pa2v2 to me.  

With a few tweaks the indeed/bravo amps sound **** fine.

I haven't heard the dt990s so I can't really comment on them, but they are supposed to be a more lively or fun presentation. The dt880s are fairly neutral. Trebles are slightly boosted but not ear piercing to me, bass is pretty good for an open phone. These are by no means bass monsters. I would...

You might watch the for sale forum for a used pair of beyerdynamics. They are exceptionally comfortable and used dt880's or dt990's should fall in your budget.

I would read through this thread. The differences between the 250 and 600 ohm versions appear to be small to nonexistent.

I had this issue with the used TF10s I bought and used superglue. Just apply a little at the joint between the two pieces, maybe use a toothpick to apply and spread the glue out. Mine has been fine after repair for about a year now.

My Bravo v2 has no problem driving a pair of K702s, I usually have the volume at around 9 o'clock.  If you get a Bravo do yourself a favor and read the threads here and on rock grotto about them.  There are several cheap diy mods that make a major improvement in the sq, and good cheap tubes for...

They sound pretty good out of the Bravo/Indeed hybrid tube amps.  I have a bravo v2 that I've upgraded the mosfets and fixed the crosstalk on and I feel they synergize pretty well.

The 840 pads are deeper than the stock pads, even compared to brand new stock pads. Imho this makes them quite a bit more comfortable, it is probably why the soundstage increases a little too.  I think they are a big improvement overall.

If you've ever had a car headunit with a "loud" setting they sound kind of like that.   There is an emphasis on the bass and treble with recessed mids.

From the thread on rg it appears that the regular hd681 is the bass oriented one and the b model is "balanced" with less bass.  http://rockgrotto.proboards.com/index.cgi?board=review&action=display&thread=5352

I have both the pro 700s and the hd681s.  I'd go for the pro 700s if there is a reputable seller still around, otherwise the hd681s sound amazing for the price.  There are a couple of long threads about them on rg http://rockgrotto.proboards.com/index.cgi?board=review&action=display&thread=4559...

The pro 700 sounds ok out of my mackbook unamped.  Here is a review http://www.head-fi.org/products/dbi-pro-700/reviews#3893

I have both the dbi pros(both kinds) and the m50.  I honestly couldn't pick between the m50 and pro700 as to which sounds better, there are pro700s available on ebay again for $40 shipped and that is imho an incredible value.

The superlux hd681s have been getting a lot of attention on rockgrotto, I've been meaning to pick up a pair to see what all the fuss is about.