Right now, while writing this post, I am enjoying my friend's older 0015** revision model. I had borrowed it for this weekend to find out the physical difference between the two. I had previously watched an youtube video about how to take parts down of an AKG model without harming the headphone, so I took the time to check both headphone internals.
I am glad you are happy with your model, but than again, you have not compared it with a different AKG product. I did, and I also used in the past a pair of Q701’s. I never told that midbass and sub-bass of my K712 wasn’t there (0093** revision), I've been complaining, It wasn’t the same volume (db) lvl, compared to an older, 2014 year model, 0015** revision.
After an extensive A/B comparison, I would like to add further observations. Besides the different lvl in bass, the two exactly same headphones (K712) , sound difference in more areas, not bass lvls only. The newer K712’s also share a hump in the upper mids (1kh) region. This makes them brighter and kind of more fatigue headphones, in direct, A/B comparison between the two. So, not bass only, the mids are also different, mine are definitely brighter.
Final observation – the decay. It’s also different. The newer model has a much faster, almost non-existent decay. This makes it sound almost artificial in comparison, since in real world, music sounds different, it echoes from different objects, it reverbs, it does not disappear instantly. The decay I hear from the older K712s is different. It’s much faster then Sennheiser decay (HD650), but it’s definitely slower than in my newer model.
To put a summary , the newer K712s , 0093** revision, downgrade compared to the older models in the following aspects:
a) Bass general lvl is 3db lower, which sets the bass behind the midrange (behind the vocals), not the same layer as in older model.
b) Mids are brighter because of a distinct upper-mids hump (1khz-2khz). This cause fatigue .
c) The decay is almost non-existent, sounds disappear instantly.
Don’t get me wrong, the newer K712s are a good sounding headphone, but they don’t scale as good. Besides, Q701, K702, K701 were never considered a bad sounding headphone. The performance is right there at the lvl of mid-fi, 250$ headphones. The true K712’s , however, scale much, much better, they can do a comfortable competition for twice as much costing headphones, hell, they can sound better than a planar magnetic monster and even HD800s. Not mine (the newer one, 0093** revision)…
Ok. Now, let me share my physical difference observations.
I had made photos of the insides of my headphone. Please, take a careful look at my photo, and the one found in google for K712s. The drivers on my model have a distinct red line recess. It is present on both drivers. Not present in the older K712 model.
Unfortunately, this was the only visual difference, between the two. I had also taken away the back side of the headphone and found the exactly same parts and wire configuration. I took the time to examine everything. Even the small red and white wires had the same label. This made me conclude, my Honk-Kong K712s are not fake. These are genuine, original K712 Pro. The only remaining option is blaming AKG themselves for cheating on the customers. They should had made a distinct model for studio needs, not change the original , more audiophile oriented tuning.
The newer K712 don’t sound bad, but audiophiles like you and me won’t get the ultimate headphone, you’ll get another nice pair of headphones, that has it’s flows and positives, but you’ll gonna sell it in the end, because you don’t want that analytical presentation, you want a more life-like reference
skingg, could you please make a picture or share the link of the exact
warranty sticker, since I don't find anything like that.
well that'll be nice!
