AKG K612 Pro -VS- Audio Technica ATH m40x

[3ee]

I wouldn't ever recommend mastering on headphones. HD600s are very common with mastering engineers, but not for doing the main work on, just for QC checking at the end.

I only want a pair to check mixes (and masters) on.
Have a fairly decent treated room..
also an IR eq system to compensate the frequency response to check the low end

[3ee]

OK, this might be a stoopid question (mainly because I don't know how it works) but...

What if I burn-in the headphones with a significant bump (about +8 db) right where the freq boost is in their freq response?
They might settle-in differently, more flat me thinks it might happen! thought?

here's the freq response I found on the web: AKG K612 Pro

[Shy]

Don't use noise to burn in headphones, use music, and not with some huge overall frequency bias. You can't "punch in" a frequency range bump or dip by playing back equalized noise or a synthetic tone, and you can't know exactly in what ways headphones that are not burned in are inaccurate (compared to the final, "settled in" response). "Static" noise has no transients and it may be harmful to make headphone or speaker drivers work continuously at high volume for so long.

[3ee]

OK, thanks for the tip, then I won't really bother with burning them that much... Will just let time do it, I'm sure that in a month or so they will settle in more or less regardless...

Well, then I guess I'm settled for the AKG K-612 Pro, will post my experience after they'll get here...
again, many thanks guys for your comments!

[3ee]

OK, right out of the box: the K612 Pro (made in china)

No headphone amp, sound out of my M-Audio Firewire Solo headphone preamp.
(Had to drive the volume a bit more than expected but getting some pretty hot levels at max... but usually for mastered stuff about 60% is fine "normal-loud-ish")

A bit about build quality:
Is OK, has a bit of that "made in China" plasticy sheen and tiny bit of edge but I can't complain about a poor build. So a 7.5 out of 10 I guess. They're a bit stiff atm so they aren't super comfortable (no worries, I expect to be more comfortable after a week or so like many people on the internet point out)

Sound is very natural, clear and flat spectrum (some little dips and bumps from the higher-mids upwards with some slight stereo differences revealed by the sine sweep test, nothing serious).

Sound is "open" and detailed (sound character different than I expected after listening to an AKG K240 MK II for a bit)

Dynamics seems snappy and very responsive (also tested with some synths with very good envelopes)

Highs seems a tiny bit brittle-ish (not harsh) but not annoying.
...after studying a bit about headphone burn-in I highly suspect that a little burn-in will smooth up the sound a bit.

Stereo Image seems more or less like on my near-field monitors (from what I had read, I expected a wider image but I'm glad it's "normal" and not too wide)

I'm happy with the headphones so far, will mildly burn them and post my experience with them after!

[3ee]

After burning them for a little bit (3h + 1h + 50 minutes) I already feel some difference, the sound became more "unified" and the brittle nuance sound is no more or unnoticeable anymore (would actually been interesting if I had a before and after graph, feeling that the highs have smoothed up about 1 db give or take. )

I used different volumes but mostly the same (medium to medium loud) I put the headphones on and raised the volume on the noise until it was reasonably loud while still sounding great (the sound gets a bit driven past 70% here anyway so I guess this is the built-in headphone amp and not the headphones + that slight -digital- shade might be the quality of the preamp as well)

I used this little file I made for the "smooth" burn ( https://app.box.com/s/ewv1108i5mdypp2ta4bt ) and will have to burn them in a bit with "transient" material too. I'm planning to simply listen to music for about a month for this instead of having a test that might -damage- the phones if not used properly.

So far, I'm very satisfied with the headphones!
Will have to get myself accommodated with the sound to give more comments...

Update on the comfort: They already feel more comfy to wear regarding the strap/clamp, I do feel that my ears are getting a tiny bit hot though...

The only thing I can complain about these headphones is that they don't have a removable cable!

Some more things about the sound atm on the sine sweep:
Bass seems very linear/flat, it's tight and sounds awesome IMO (not emphasized by one bit), it does resemble the -5 db cut at about 30 Hz and downwards like that graph is showing... that's no trouble of course. The overall highs seem slightly accentuated (like with AKG cans in general I assume) but can still easily fit them into the balanced/flat category. (I really think I can work with them easily after I get to know them)

The slight bump in the mids about 2-4 k doesn't actually seem like that when listening to -complex- sounds instead of a simple sine sweep. The bump is followed by a short dip @ about 5k... after that small dips and bumps here and there... but I don't hear much past 15k, maybe it's because my age)

It's interesting the tonal change if I try to cover the outside part of the cups with my hands (feels notchy with some 1-4k oddness, this is a slight tonal change though)

[3ee]

Bump... have the K-612 Pro model for over a year now...

I work with them, let's say 80% monitors and 10-20% headphones (I also have a "grot-box" pair of headphones now, the Apple Earpods) ...

These headphones are great especially for the price if you ask me, ... although a tiny, tiny bit on the bright side, the highs have smoothed out after a good while of using them, they really help to point out resonances and more subtle stuff like clicks and noise and I couldn't really work without a good pair of reference headphones anymore...

One thing I noticed, (and I guess is valid for all headphones) if you push them harder the bass/kick/low freqs isn't as punchy as with the same relative volume when listening on nearfields for example, so if you don't have that in mind you might compensate freq balance in the low-end freqs