AKG K340 Electrostatic-Dynamic Headphones

General Information

A discontinued electrostatic-dynamic hybrid headphone with an electret transducer for frequencies above 4kHz and a moving coil transducer for frequencies below 4kHz. The headphones employ passive diaphragms similar to those in the AKG K240 Sextetts. The nominal impedance for each channel is 400 ohms.

Latest reviews

Pros: Long life, used in both studio, live sound, and for fun
Cons: after buying them new in 1987, the foam is a little worn, wire tension on the pods is a little loose
When I first began my career, I was looking for some inexpensive but good quality headphones for my personal reference. The K340`s were less expensive than the cream of the crop at that time, the Staxx system with the discrete amp, etc. Over the years I have had no problems with the jack shorting, cord fraying, plastic breaking, etc. They have always been reliable and within the factory specs.  At the time the k340 came about, most of the less expensive headphones had the standard 3 strand wire design that was not well shielded and little separation of the left-right-gnd wires inside the mono outer casement. My K340`s have the molded 4 wire flat cable that provides about .080" separation between the conductors. I have never had problems with crosstalk or noise from the headphone wiring that I can remember. They have held up very well over the years. I have used them as reference head monitors for a number of recording projects from Margo O'Donnell, Dolly Parton, Five Bucks, to the smokey mountain travelers. They remind me of a headphone version of some JBL 4310`s or some good NS-10s. For live, the ear  foam ring does do an ok job with high spl situations during a loud show. They have survived many road shows over the years. I still pack them in the original Styrofoam vendor packaging. They are well used and loved and they have never let me  down. I am surprised that AKG stopped making them years ago, but has continued making the k240 which is the baby. I feel as though I made a decent investment those many years ago. And, if I ever need to, I can send them to Austria for a tune-up. thanks all 
I got my AKG K340s back in the early 80s. Mine look like new but I need to locate the rubber bands for the head set. I think these are pretty special in that you can forget your listening to headphones. There like speakers for your ears.
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Hi oddioengin. I have a pair of AKG K340 and am being a little unsuccessful with my enquiries here in France. I have tried Austria, France and England and they seem to be confused with the newer model K 340 which is an in-ear device. You said that you could always return yours to Austria for a tune up, so can you give me the contact details please.
Pros: Detail, Deep Soundstage, Smooth Highs, Clarity, Transparency, Excellent Instrument Seperation
Cons: Heavy, Difficult to Drive, Bass Not Very Detailed, Several Version Don't Sound the Same
I bought the AKG K340 Electrostat-Dynamic System twice. The first pair was very worn out and sounded weird so I sold them after a while. I bought the second pair from Ebay, and this one sounded very different. I used the first pair with the Beta 22 amp which really struggled to drive it properly. The second pair I'm using with Headroom Ultra Micro Amp with Astrodyne PSU, and surprisingly it drives this pair with no problem, I hardly pass 10 o'clock of volume!
I suspect that the second pair is the bass heavy version. There is a lot of bass here with deep impact, although not very detailed but not loose bass like that of D2000/D5000. It's well integrated into the spectrum of sound and adds a lot of warmth to the sound character. 
The Mids and Highs are the best quality of this pair. They are very clear, very detailed and very smooth. This is attributed to the double driver system of the K340 (electrostat and dynamic), which eventually results in a very layered sounstage of 3D holographic nature, while on the K702 it feels 2D in comparison.
Compared to my beloved K702, the violins and flutes sound very smooth and extended, while on K702 they seem very bright in comparison with slight harshness. If I don't compare the K340 to K702 and keep listening to the K702 I don't feel there is any problem with the highs, they look absolutely OK, but when I put the K340 on, the K702 pales in comparison and sounds gray while the K340 is all black and white. The only area where K702 excels is a wider soundstage (which lacks in depth) and the bass is more detailed but without the impact and warmth of the K340.
On listening to DG's marvellous CD "Fiesta" or Boulez excellent recording of Varese's Arcana on Sony, I feel like a real Orchestra is playing on the stage, giving the instruments a great weight and impact that I never felt with the K702. Playing Beethoven's Cello Sonata No.1 by Schiff and Perenyi  I was overwhelmed by the Cello's deep and dark sound, it was a great emotional experience that brought tears to my eyes!

On listening to the K340 I only think about the music and the composer who created it, while on listening to the K702 I only think about the good sound quality! 
Considering their price range of 150 to 200 those cans are a steal, they can beat HD650, HD600, K702 and even my recabled K400 in performance. They are not perfect but considering the price and value they are a real treasure!
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Totally agreed.
This is the pair of headphones when I bought once I got my first salary 20+ years ago.
After those years most of the other gears like CD players, amp, etc were all gone, but this is still working fine. I recabled it with Cardas cabel, and drive it with a sinlge end tube amp ( Darkvoice 336 SE), and the sound is second to none of the moving coil competitors. The only HP which can beat it should be a Electrostatic.
I agree. What makes it so unique is the elecrostatic driver. I don't believe that AKG are eager to create a superb cans like those anymore!
Pros: very articulate can with great mids
Cons: good but not great detail
This a great cans , but very hard to drive. Vocals never sounded so clear and articulate, bass is good , but not great.


I listen to them for sometimes now,i heavily modify them, and my audio system is heavily modded also, and this headphone now sound so good that they are absolutely no comparison between it nude or modified in a clean audio system... Defects that many people report are there no more,or way less evident, after cleaning the electrical grid of your audio system and modify the AKG (pricipally grid mods,and damping with sorbothane and stones) Their principal sound quality is depth imaging like my speakers with a sound so natural that they kill my Stax SR-5...Anybody who listen them nude ,in a non cleaned system, does not know them.... I think that short of Stax omega or many thousand dollars headphones they cannot be beaten...I does not search headphones anymore ...i pay them 100 bucks...Must i say i steal them?