The headphones could be characterized as closed for recording vocals without bleeding?

Yes, if they fit you well enough to achieve a good seal.
 
If they don't, then you can retrofit them with Brainwavz angled pads which may seal better on difficult heads, and change the sound little if at all (to my ears at least).

Massdrop has these at $119.99 for 5-6 more days. Heckuva deal. 

By the way, I never saw Tyll's measurements of the k553

AKG k550mk3 and k553mk2 are very different.

firstly, both of them are better than 545 so please dont compare these to them.

AKG K550mk3 is leaned to treble and 553mk2 is leaned toward bass with 2dB boosting effect.

553 sounds deeper and 550mk3 sounds taller.

the difference is the paper damping the holes(they are different)

but hey, do a solderdude mod on k550mk3 and get akg k501 (annihilating soundstage, clarity and image....this is bigger than k712) and bass extension of closed back, with neutrality in check

I know this is an old thread, and IDK if the OP is still active here on Head-fi.

But note that he doesn't mention burning in his brand new K553 when comparing them to his 2 year old K550. I'm wondering if he did so or not. If he didn't, the fact that the K550s were well burned in and the K553s were brand new could very well account for the difference in sound signature he experienced between the drivers of the two.

pinkfloyd4ever said:

I know this is an old thread, and IDK if the OP is still active here on Head-fi.

But note that he doesn't mention burning in his brand new K553 when comparing them to his 2 year old K550. I'm wondering if he did so or not. If he didn't, the fact that the K550s were well burned in and the K553s were brand new could very well account for the difference in sound signature he experienced between the drivers of the two.

Click to expand...

I have both the K550 and latest K553 - both with replacement cable mods done by professional (on this site). My K550s are very well used and highly burned in after years of moderate to high usage. My K553s sound similar but definitely have lower and more detailed bass extension. I find however my original K550 MKII's have more detailed imaging in the mid range to upper range however than my K553 Pro's. My K550's are also definitely far more comfortable IMO than my new K553s. My K550 pads (in great shape) are also softer than the K533 pads. They appear identical in size. The clamping force on my new K553's is fairly high and I actually can't wear them that long without them becoming uncomfortable. Probably over time and usage, the sound and fit of my K553's will improve but may never sound like my K550's. I actually like both for different reasons and for now I'm keeping both of them.....