I'll try. I currently have the K7XX but before recently getting them I had considered the K712 Pro as well. At that time I was fortunate to get the impressions of a knowledgeable friend who'd compared them both for me. He owned the K712 at the time. I don't think he'll mind if I paraphrase some of what he noted as the relevant differences:
- The K712 has a more neutral bass and sounded slightly wider and airier to him. Otherwise, they were very similar in sound if not identical. Akin to the K7XX, he still found the K712 to be balanced, well-rounded and musical despite their revealing nature. They both use the Annie pads, so he chucked the few discrepancies up to the drivers being different (analysis of the various parts documents seems to support this). Other build materials are the same between the two but he found the external fit and finish on the K712 to be tighter and better. The K712 has nicer packaging and more accessories; one 3m straight cable, one short coiled cable, an 1/4in adapter and a velvet carrying bag. The K712's support rods and straight cable are copperish-orange with the rods also having a faint glitter finish. -
During one of the recent K7XX drops, he decided to return his K712 and purchased the K7XX (he had the option). Even if he had snagged the K712 for $90 more than the K7XX's going price, he didn't feel like the subtle differences were worth $90. Obviously, I didn't find those differences to be worth $90 either but others might have a different opinion. Hopefully this helps. I trust his opinion, but of course you can decide for yourself.
I've had the AKG 712 pro for over a year now. I do genuinely love the sound quality but my pair creaks and sqeaks all the time. My pair was made in Austria. Obviously this happens when bits of plastic meet and rub together but for £250 I do feel like AKG should have taken this design flaw into consideration. I have plenty of other cheap headphones that don't make any noise. I use my pair for music production and mixing reference especially. When theres no sound/music it's hard not to notice the creaking and it's bloody awful if for some reason I need to re-adjust the headphones whilst I'm wearing them, open my mouth or move my head. Sometimes they'l creak and sqeak even if I'm not moving. It just makes me think bad cheap manufacturing. The creaks/squeaks are originating from the earcup pivot points and where the clear plastic bits on the side meet the leather strap. I have tried various lubricant solutions but nothings has done the trick yet unfortunately. Does anyone else have this problem and if so are there any known remedies? Thx
Probably the review of lachlan could help you a little, there he compares the Philips Fidelio X2, he 400s and k712
??? The K712 is the same basic design as the k701 and k702 that have been around for many years. I've owned K702's for over 5 years and I've never heard the "squeaks and creaks" you're describing. If you could be more specific as to which plastic parts are rubbing the wrong way it would help us understand your discomfiture.