Pros: Sounds good with all genres.
Cons: Sounds slightly "grainy".
Found these classic headphones at my local thrift store for 20$! I just had to pick them up immediately when I saw them. Lucky I was, they were in perfect working order, and also cosmetically in a good shape.
The sound?
When I first heard them, I was really surprised. Since they were "monitor" headphones I expected them to sound ear piercing, with little or no bass, but wrong I was. The AKG's have a natural warm sound with solid bass and plenty of detail.
So let's compare them against the 400$ Sennheiser HD600's, and see how they hold out?
Bass:
The AKG's have slightly more oomph than the Sennheisers, but the nature of the bass is very similar; it has a nice mid bass impact, but is never overpowering. However I find the Sennheiser's bass to be tighter, while the AKG's sound slightly "bloated" at times. Both have a bass rolloff at around 50hz.
Mids:
I find the Sennheiser's have slightly more "tight" mids, in a way they sound sharper, more accurate. Sennheiser also has the edge on instrument separation maybe due to this. The K240M sound slightly compressed in comparison.
Highs:
I found the highs in the HD600's to be somewhat cleaner, more "airy" and sparkly, than the AKG's. AKG's top end sounds slightly "grainy" in comparison.
Overall:
When compared with the HD600's, the K240M's don't sound bad at all, which is quite impressive considering the HD600's cost 4 times more.
This is just a quick review, I will edit this later. Now off to sleep!
BR heinz