I own the Ultrasone DJ1. The mids aren't recessed at all. The M50s have more of a dip in the mid section than the HFI-580 does. AT has addressed the mid section on the M50 on their earphones the CKM500 which has a lush deep mid section. AT has changed the way they do sound tuning and is use a much more balanced sound signature on their newer headphones and earphones. The WS55, CKS77, CKM500.
As for the HA-S500. Yes. They are shockingly great. Carbon nantube drivers are no joke. You guys can read the thread here. http://www.head-fi.org/t/621063/the-new-jvc-ha-s500-40mm-carbon-nanotubes#post_8581957 There are some guys that Achmedisdead who bought and loved the WS55 is now loving his new HA-S500..The thread is filled with overwhelming praise on the new headphones..
I've been reading relentlessly on this site (and others) and have finally pulled the trigger on a pair of headphones (take 2). I'm just sharing my thought process in case someone else is hesitating and has similar needs, and maybe someone will respond to my assumptions...!
I mostly listen to electronic music on my iphone but will also listen to rock on occasion. I had initially purchased the Sony XB700 and spent a whole 7 hours straight listening to them, I was in love (newbie that never had any type of decent headphone/earphone on his head before) I felt the sound was very appropriate for my listening habbits as I like bass but also enjoy hearing every sound clearly.
Unfortunately I had to return them as I want to be able to use the headphones on long bus rides and the XB700 had open slots on the cups which leaked sound way too much for me to still consider myself a respectful person when using them on the bus...
Now I had to find a replacement and was debating between:
Pioneer HDJ-500 (auditioned)
M-Audio-Q40 (i think that's the name) - but that didn't last as I was too afraid of sound leakage and couldn't audition them
JVC HA-S500 - (Weren't part of short list untill the very end)
As I read on and on, and also testing the HDJ-500 and M50's, this is what I thought:
HDJ 500 - Nice sound, big bass, on-ear but not uncomfortable, limited sound leakage
ATH-M50 - Crisper sound, especially noticeable in snare-ish sounds from an EDM song I listened, felt like I could hear the drum snap more than on the HDJ. The sub-bass was more pleasing on the M50 but the rest of it was lacking (in my bassy preference) compared to the HDJ. Highs were maybe a bit to clear I thought, but then I went back to the HDJ and thought they sounded a bit muffled on these HDJ's now that I had listened to the M50. Comfy enough for me, but I do prefer around ear (M50) to on-ear (HDJ500). Just a bit more sound leakage than HDJ. Minor annoying detail, the M50 plug did not fit with my iphone case, the HDJ-500 plug did (wasen't the Iphone version either).
At this point I thought I wanted something in between the 2 :S - (great...!!) Not many places offer to try headphones... I also tried the sony V55 (or something) but I prefered the HDJ500 (also cheaper)
As for prices well I could've got the HDJ for 90$ and the M50 for 120-130, so a bit of a difference here.
Then I read about the ATH-WS55 (90-100$) and thought these were my best choice. But couldn't audition them... So i hesitated for a while, and at the last minute I went for the JVC HA-S500 (70$ shipped + possible hanlding at customs and tx.).
What I expect to get out of the JVC HA-S500:
A bit less bass quantity (unfortunately) compared to ATH-WS55 and more so HDJ-500, yet still good presence and definition.
Sub-bass a bit closer to M-50 than HDJ in definition as lesser presence of the mid bass than with HDJ. Maybe comparable to WS55 (but I haven't heard those)
Good sound isolation, and low sound leakage.
Overall bassy headphone, that still presents all sound frequencies with a bit less emphasis on highs than M50, but not as muffled as HDJ (which aren't that bad).
Here's hoping I don't get something too clear sounding and thin in the lower ends! Rather something between the M50 and the HDJ-500 soundwise. I'm just a bit worried that I should've just went with the ATH-WS55...
Again thank you for all your input, special thanks to Dsnuts!