I've been shopping around for another pair of cans to add to my collection, with an eye toward open-back models since I don't currently have any. I have two goals: an additional reference to complement my existing headphones, and something suitable for pleasure listening on my portable MP3 player.
 
After considerable research, I've concluded that the AKG K701 meets my first requirement. Its frequency response is almost a mirror image of the ATH-M50s that I use most. Should be a great alternate reference.
 
But many reviewers say the same thing: you can't use the K701s with an iPod. Not efficient enough, too high impedance. Hence my query here. I don't use an iPod, I use a fancier unit that drives my other headphones just fine. But I'm concerned that the AKGs might not work well with it.
 
My ATH-M50s have a fairly low efficiency rating of 99dB SPL/V but low (38 ohms) impedance and they work OK. The K701's published specs boast 105dB SPL/V but a higher (62 ohms) impedance. It's possible that even though they're more sensitive they'll still require more power to get the same volume as the Audio-Technicas.
 
My question: if you use K701s for mixing, have you ever tried them on a portable player and found them to be a) wimpy, b) adequate, or c) superb?
 

To me, my new Q701s sound about as efficient as the old AKG 240M I had a few years ago even though the 240M spec out at 88db (600 ohms). I love the sound and it does not bother me that they do not get very loud. They get loud enough and I do not listen to them in a noisy environment. Love them for tracking and mixing. Unfortunately, I have no experience with using them with portable gear.  Might be a challenge though given the combination of open air design and being on the power hungry side.

Thanks for replying, Steve.
 
I'm still trying to figure out the deal with impedance and pocket players. There's such a wide variance in impedance among headphones that I'm surprised they are as interchangeable as they are. I can only presume that the players have a very low output impedance.
 
According to my calculations (using nothing more sophisticated than George Simon Ohm's handy law), your Q701s should indeed be about equal in volume at a given power output as the K240s, and both of them should be more efficient than my Audio-Technicas. You may have answered my question.
 
 

I have some AKG 702's. Not sure of the difference from the 701's. They sound great with an iPod but the volume is a little low. I'm not saying they're not loud enough but with the iPod turned all the way up they are not real loud. I would sell them if you wanna try them.

Thanks for the reply. Sorry I just got around to reading it; I've been incapacitated this past week. I read somewhere that AKG considers the K702 as the replacement for the K701, even though they"re more expensive. Once I'm able to get back to my computer I'll do some more research and maybe talk about a purchase deal.

Duplicate post.

Duplicate post

Just noticed this slick new forum software will hapily send the same post 3times in a row if you press Reply 3 times! Not a good feature for the impatient user. Like me.

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