I've been in the market for some portable headphones, and I have been especially eying these two. First, I'd like to share some background about my subjective tastes. I'm not a big fan of mid-bass. I love sub-bass rumble, but in my experience mid-bass tends to drown out midrange and vocals when too excessive. Midrange and especially vocals is my favorite range. I love female vocals. I'm also a fan of treble due to the genres of music I generally like such as rock, pop, and electronica. Treble gives a sparkle and a sense of excitement for me, and since the music I listen to are generally fast paced, treble is important. One thing to note about treble, however, is much like mid-bass going into the mids, there's a range in the upper mids and lower treble that I find distasteful when elevated. I believe this is the range that also cause sibilance.
I will be playing both headphones straight into my HTC One smartphone. The music player is Poweramp. I'm choosing to do this because the main purpose these headphones serve for me is for when I'm on the go, and don't have access to a DAC or amp. As a benchmark, I will be comparing both also to my Beyerdynamic T90 hooked up through Schiit Modi and Bottlehead Crack.
These came in today and I've had them on all afternoon. Coming from around the ear headphones for so long, I found these on-ears to be quite uncomfortable. I had some co-workers who are used to on-ears try them out, and they say these are more comfortable than what they're used to. The clamping pressure on these are minimal, however, it still does distort the shape of my ears to the point where the upper tips and back edge of my ears are touching my skull. With low clamping pressure and memory foam pads, I'm sure these are among the most comfortable on-ears, and if you're used to on-ears, you wouldn't mind the comfort. But for someone coming from around ears like myself, it may take some getting use to. I'd like to note that my ears face outwards more than the average person, so that may play a role.
The discomfort for me was so much that during the first hour I really could not get into listening to the sound because I was too distracted by the discomfort. However, thanks to the adaptive qualities of the human body and our ability to zone out constant senses, it got a lot better. I found the sound to be surprisingly good for a pair of on-ears. The bass was punchy, the mids very clear and fluid, and the treble, while not as exciting as I'm used to, it's definitely there. I'd say much like the frequency graph advertised on the box, the M500 has a very flat sound with nothing elevated or lacking.
I stopped by Best Buy and picked these up after work. I had demoed them for about a hour in the past. These are around the ear headphones, but barely, as they still keep it small and portable. Luckily for me my ears fit perfectly, and have no problems of sides being squished against the inner wall of the pads like I did with the Sennheiser Momentum. The clamping pressure is much more apparent compared to the M500, but since it's not pressed against my ears, it's still much more comfortable than the M500.
From memory I remember the P7 to have a very powerful and impactful bass. So much so that I was shocked at how close it came to my Hifiman HE-500 through a speaker amp in impact. And this is coming from a phone. This notion was reaffirmed today. The bass mentioned here includes both sub and mid bass. The mids are not recessed, much to my surprise considering the powerful bass. The vocals, from first impression are not as natural, in my opinion, compared to the M500. It sounds a bit congested and compressed. However, as I found, the M500 does not win hands down even in vocals. I found the M500 to struggle in the upper midrange when the volume goes above 70% on my phone on female vocals around the 3-4 kHz range (usually sung at the end of verses). When played at higher volumes, the highs of the upper midrange starts going uncontrollably piercing in nature, much like feedback in a mic. Of course, this could likely be fixed with proper amping, but that's outside of the parameters here. I found the P7 to not have this problem surprisingly. Perhaps only at max volume does it start getting a bit uncomfortable, and even then it's mainly due to the volume in general, and not a specific high midrange frequency. The treble of the P7 I remember to be it's weak point for me, and it still is. The M500 was already a bit on the light side for treble for me, but the P7 is even more recessed.
Honestly I have to admit my first impression putting on the P7 after an afternoon of listening to the M500 was wishing that the P7 had the M500 driver (this would be a hell of a mod, but dangerous and expensive too). While bass impact is nice on the P7, I find the mids and treble on the M500 to be much better. Especially in vocals, as long as I don't play too loudly, it beats the P7 hands down. The experience reminds me of how I found the MartinLogan vs Focal speakers and their presentation of vocals. It's like listening to vocals on 128 kbps on the P7 and Focals, as compared to 320 kbps on the M500 and MartinLogan.