First of all, hi there! I have been reading and digging around quite some time at Head-Fi, but now I'm really in. This forum is quite addictive, I fear for my bank account...
After 4 years of occasional use of my K701 I recently started to use it more and more. But whereas I used to run it with a Marantz CD player and an Aune X1 Pro dac/amp, I now use it mainly with a Macbook Pro. Period. No dac, amp or any fancyness in between, though I know the K701 really needs (and deserves) a decent amount of power to make it sing. But without the necessary power it's terrible! A macbook is no match at all for a K701, the harshness and coldness was unbearable. So I started searching for inexpensive ways to solve this and stumbled upon this modification. It took me several hours, a lot of swearing, a few drops of blood and I ended up with battered grills. But man, it was worth it.
The original sound of the K701 is amazing to my ears. I kind of grew up with the K501s of my dad and therefore am a bit of an AKG fan soundwise. I love the airy, open sound, the details in the upper mids and treble, the detail and texture in the lows. And with decent music and decent amplification really liked the way the bass is extended really low and precisely articulated, without being too loud. Then the mod happened.
First of all, just like I hoped and expected from what I read about it, it's way more enjoyable and usable directly hooked to a Macbook. Mission accomplished. But to really understand what changed I started to play some CD's on the cans through my CD/DAC/AMP setup and I was surprised. The highs are rolled off quite a lot more then I expected based on the reports in this thread. This makes it less detailed, but to my ears more forgiving on harsh voices and less fatiguing. The lows are definitely louder, and again quite a lot more then I expected. So my first impression: messed up the treble, added too much excessive lows. But then I tried to let go of the nitpicking, I tried to forget what it sounded like before the mod and I tried to enjoy the music. And it started to make sense. It's still pretty tight and textured in the lows, but sooooooo enjoyable!! It's funky, it grooves. My head automatically moves to the grove and my heart syncs up with the bassdrum. It sounds quite a bit warmer and therefore to my mind a bit more relaxed. As if I can relax more to enjoy the music. Though I have to say I understand the people who don't like it or thinks completely open is too much. The difference was way more dramatic than I expected. That piece of plastic seems some kind of magic.
The only downside to this story is that now I'd like to have another K70X without the mod for the occasional acoustic oriented, beatless records that benefit from the open/airy top end.
So thanks guys. Besides being informative and making me want to buy more stuff, you also introduced me to the world of headphones modifications.