The AKG K701s are very good headphones. The information retrieval these headphones show up is very, very good! Vocals are also very good with the K701s in my opinion, and you can hear how good and badly recorded the songs are with the K701s. These AKGs really show do up on things in the music and your set up.

In my opinion, these headphones don't do euphony. They are neutral and revealing!! If you play a song that is badly recorded, these headphones will sound shockingly bad. So be warned!

I own the AKG K240 DF Studio monitor headphones, and I have been using them for more than 10 years.
Assuming that, after so long period of time, the headphones sound quality should have improved, I decided to make a research on the market in order to find a substitute of my old headphones.
I took into account technical specifications, reviews and prices, as well as the availability of some brands in the city where I live.
Discarding other brands, I considered choosing between Sennheiser and AKG. Sennheiser was generally more available than AKG in all the shops I visited. But I have always used the AKG and I have been very happy with them, so, eventually I decided to keep on buying AKG headphones.
The present AKG top model is K701 one, but the average price I found in the shops was about 350 €, which was too expensive for my budget.
Fortunately I found a person who was selling his second hand headphones of this type at an affordable price for me.

I was impressed by the incredible sound quality of the K701. The music is so detailed, so clear, so balanced and the frequency response is so extended that I doubt anybody can find anything better, at least in this price range. I have heard that there are headphones that cost even five times the price of AKG’s, but this is another world and, anyway, I have neither the chance to listen to them nor I could afford them by no means.
I have never heard the instruments so separated and exactly situated in the sound space as I have heard with this headphones. I realised that it was time to move away my old headphones. Moreover, I have read that the sound quality of the headphones improves after 300 hours of working, so I expect a better performance after some months, if possible.

If I had to change something of the headphones, I would come back to the leather pads of my old K240 DF, instead of the velour ones. But this is due to a personal problem that I suffer, being allergic to some kind of fabric. This is not AKG’s fault.

I use a Cambridge Audio 340 SE amplifier to drive them. The CD player is a Sony CDP-X8920 Q series. Although I am aware that this is not the best equipment that an audiophile would desire, I think it is enough to appreciate the great sound delivered by the headphones.
I have clearly noticed the great differences of record quality among the CD’s I own.

Having owned the HD-600 and AKG-501 concurrently for some time in 2002, I opted to sell the 501's and keep the HD-600's. To say that I am familiar with the sound of the HD-600 is a huge understatement. Unfortunately, 7 years of almost daily use left me with the need to purchase a new set of headphones. Having listened to my boss's HD-650's, I considered that option, as well as the new HD-800.

Listening to the HD-600 vs. HD-650, there differences weren't incredibly large, and perhaps not significant enough to justify the price difference. Then I noticed a set of AKG 701's used locally. I looked at the specs and surmised that they were best driven with a dedicated headphone amp (I have four currently), and the used price was hard to beat, so I went for them.

These are a gigantic improvement over the 501's IF you have the power to really get them going. I found that a Headroom Airhead didn't quite do the job, but a Bottlehead SEX amp (2 watts @ 8 ohms) was more than adequate. Compared to the HD-600, these have a far tighter sound to them, and they really stay composed with difficult material. I noticed at first that they sounded very, very hard. This characteristic seemed exaggerated with the Headroom amp, especially in the lower octaves. After letting them play for a little over 100 hours (they were used when I got them, but not well broken in), the sound has softened and the tunes are sweet. The bass control is out of this world! For the price I paid, I couldn't touch anything close to comporable in the Sennheiser line. Also, these are some very comfortable cans. The large padded ear pieces provide enough pressure on your head to hold the headphones in place, so the downward pressure on the top of your head is nill.

Overall, these are a killer deal for an at home headphone. Don't even bother running them without a dedicated amp. An iPod or Zune will fall way, way short of what this headphone can do. Even some smaller portable amps are debatable.

Clarity.
Smoothness.
Comfort.
Price.

You will need a headphone amp if your receiver, pre/pro or pre/amp doesn't have one built in.

These are without a doubt the best headphones I have ever listened to.
I use headphones to listen to music after my wife goes to bed to maintain peace in the house, and had been using AKG500's for a few years. I decided to upgrade about a year ago, so I took my AKG500's with me to test against different models at the local hi-fi stores. I listened to Sennheiser 600, 650 and a couple of Grado models (I don't rember the model #'s) in the $200-$600 range. Nothing I listened to came close to the AKG 500's I already owned.
I then decided to order a pair of the AKG 701's over the web, since no local stores carried them. They had gotten great reviews, and since I could return them if I didn't like them, I had nothing to lose.
I didn't return them. They sound great. Far better than the AKG500's, which were better than anything I had auditioned.
My SSP (Anthem D2) has a built in headphone amp, which I'm sure helps the sound quality greatly. Like many good headphones they need an inboard or outboard amp to get the most out of them. These are not meant to be used with an iPod.
The sound is clear and neutral. The bass is very good for headphones. I have yet to hear floorstanding speakers that match the sound from these cans. I'm sure there are some, but they are out of my price range.

Similar Products Used:

Sony's, Sennheisers, Grado

Great sounding cans after extensive break-in period. Mine took a good 3 weeks of being played 24/7 before they sounded really good.

Comfortable around ears, lowish clamping force (unlike vice-grip Senn '600's), don't feel hot after long periods.

Could use a bit more dynamic impact and bass response could be stronger, so -1 Star for those.

Similar Products Used:

AKG K240M, Sennheiser HD 600, Sony MDR-V600, Sony earbuds (unknown model #), Koss Pro 4AAA+, others.