Pros: Solid bass, detailed highs, fairly neutral curve, great for studio mixing, ridiculous price value
Cons: Metallic tint to sound, doesn't sound "real", highs grating when loud
Ahh, the Audio Technica ATH-M50: possibly one of the most positively talked about headphones of all time, and a smash hit for Audio Technica. This headphone really hasn't stopped selling like hotcakes since it's release. Walk into any college and you're going to see almost as many kids walking around with these as Beats (ok well maybe half as many). This is because people have been recommending them to audio noobs pretty much for as long as they've been a thing, so for many people this is the begining and end of their experience with Hi-Fi audio, as many people I've recommended these to say they're good enough for pretty much everything and never buy another pair of headphones until they buy another pair. While I personally think they end up being a bit overhyped when compared to some other headphones (granted, in a higher price range) due to the harshness of the highs, and their overall synthetic, unrealistic tone to my ears.
Let's go with positives first, these cans have great bass that can really give you that hard-sub feel you want from bass heavy music like rap and house. They have a fairly comfortable fit that has served me well for years, as I use these on the daily to produce everything from hip hop beats, to indie music, to witch house in my home studio that i record many artists in, as well as running from my laptop when I produce hard hitting dance mixing for my DJ sets. They have enough bass to let you hear a general idea of what people listening on headphones that deliver heavy bass are going to hear, while still remaining fairly neutral, making them perfect for anyone who intends to due studio mixing for others to hear. You could also plug these into a smaller end amp and have yourself an great entry-level audiophile setup as well for those looking to dip into the now-crowded premium headphone market.
There are some downsides to the universally hailed M-50. The first I would say is how harsh the high can be at loud volumes, but I already mentioned that. The second would be that the highs and mids have somewhat "fake" sound to them. They don't quite sound real, and almost come across as being a bit metallic or synthetic. This is probably my biggest annoyance with these headphones, and it is especially noticeable on songs that use the pure highs of something like and 808 drum machine hi-hat, or a loud mixed crash from a drum set. The cord is also a bit long, and they aren't the best for portable use. Overall, however, these are incredible headphones for the cheap prices you can get them for today. I think you can snag a paid for something in the $90 range on amazon now, so if you're looking at getting a great workhorse studio monitor, or your first set of real Hi-Fi cans, these are the way to go for any budget under 200 dollars.