AKG K-712 Pro

I compared the sound with a beyerdynamic dt-990 and the better sound quality especially for spacial recordings (live concerts, field recordings) is obvious. Great.
My synths sound a bit too thin in the low ends, but thats fine.

My biggest problem with the HP is the sound the plastic shell produces when I move my head. It is made to shift slightly to adapt your head's position (why?) and that gives a terrible squeaking sound.
I thought it was a production mistake, so I send it back and got another one (thx thomann!), but same issue. My partner has the same problem with it, so it is not only the shape of my head.
Also, I read about it online already, (people suggested to add some grease to the plastic to make it stop...:) , so it must be a thing for some people.

Also, the long and stiff connection of the cable touches my cloth, when I wear hoodies or shirts with a collar, and that also produces a noise.

Built quality; plastic, with a leather strap.
The sound quality is okay.
They have no bass what so ever and muddy sound... not really recommended for anything other than gaming.
The only plus these have is that they're big and light...
If you want headphones or IEMS that have bass and good quality, i recommend Truthear x Crinacle Zero, pretty bassy with good sound.
These headphones are just brand, you're paying for brand here. K371 are good headphones. These are not, I regret buying them... Too late for a refund i recon at this point... also too lazy, they fit my needs anyway.

I bought a pair of K-712s just over two years ago, the sound quality is impeccable. The comfort is brilliant especially for extended listening sessions, I would forget they were even on my head.
Sadly after two years of use the elastic, which is the one thing that manages the extension of the headband and how the headphones sit on your head, has deteriorated and become next to useless. The headphones used to sit comfortably around my ears, but now they are held on by the tops of my ears and will slip down to my jaw.
After looking around online there are other users who have had similar problems with their pairs of K-712s. Given that headphones can have very long lifespans if cared for properly it is a massive disappointment to have these become so loose that they slip off my head after only two years of use. They were stored safely in a hard case when not in use which wouldn't lead to over extension of the elastic.

In summary I would avoid these as they have one single point of failure which is known to fail over time.

I was lucky to use my brand new unit for two or three times. When I was trying to change the cable, the mini XLR port got into my hand with couple of wires. So when I see little bit further I saw that there were no threads inside the housing but in the XLR port.

It is totally a design fault.. might be the whole production line lot could be effected with this issue.

So I return this product back to thomann and they have replaced with another brand new unit. I'm still waiting for it and I'll give a feed back once I received it.

Great service. They just replaced.. Thank you thomann.

If you are buying this product, please be careful with this issue.

Clarity and comfort is very good with this product. I love how K712 Pro sounding.


UPDATE:
I received a brand new item again from thomann. The delivery was so fast. Great service and thank you..

About the product:
Still I have a doubt when I check the mini XLR port attachment. So when I unplug the cable, I'm always so careful.

My Suspect on how that loose coupling can be happened is as follows:

When I open the both of the boxes(the previous and the new), I noticed that the cable that had been plugged in to the headphone, the end of the mini XLR port (toward TRS jack) was sit on the bottom side of the card board holder tray that hold the headphone inside the box.
It's like holding the headphone by the mini XLR jack assembly. All the weight of the headphone hold by the mini XLR jack assembly.
Since the headphone is not tight enough inside the box with in the cardboard tray, when it's moving or transporting, it might cause to loosen the mini XLR port attached to the housing of the headphone.
So still it's a design fault.
May be thomann can send this feedback to AKG...

BUT STILL I LOVE HOW AKG 712 PRO SOUNDING and the COMFORT.

I CAN RECOMMEND THIS PRODUCT.
But be careful when you unplug the cable.