The AKG K340 is a one of a kind headphone produced by AKG that employs two drivers system: Electrostatic and Dynamic in one cans. This was a top-level cans back when it was produced. Selling for $300 in the 1980s. The headphone is highly innefficient, requiring only the most powerful kind of desktop headphone amplifiers, and definitely more suitable driven by a speaker amplifier. The now discontinued K340 had several versions while it was produced. The exterior is the same, but you will notice the difference once you plug in the headphones, and/or by dissecting the headphone and seeing the colour of the driver.
The K340 is one of the hardest headphones to drive, second only to the K1000. Ideally, you would plug these in to a speaker amp, but having experienced driving headphones with some speaker amps, I find that while powerful, they don’t have the refinement in sound that headphone amps have. Thus for this review we will stick to using the Beta 22 amplifier. On a gain 8 Beta 22 (Single ended), playing classical recordings out of a desktop CD Player, the volume is on 1 O’clock position. Quite heavy indeed.
If you know that this phone was sold at $300 in 1980, then you would immediately realize that in today’s money, it would outclass today’s top-of-the line AKG, the K701/K702. Indeed the K340 have highs, instrument separation, and speed that the K701 can only dream of. While the K701 is a regular open-design phone with dynamic driver, the K340 employs an electret driver for the high frequencies, a dynamic driver for the lower frequencies, and six passive radiator technology like in the K240 Sextett. I’ve listened to the K340 before, and I thought the sound is very thin and doesn’t offer much musicality. However for this review, I am listening to the Bass Heavy Version, and now that we have the bass back, we can start listening to music.
The K340 Bass Heavy Version is actually not a bassy phone, as the name might suggest. The reason that it is called Bass Heavy Version is because most K340s tend to be very light in their sound signature, lacking body and bottom frequency. The Bass Heavy Version, however, is what I would call a neutral phone. Something along the line of Sennheiser HD600 and Grado HP1000. It’s neutrality isn’t really everybody’s flavor, and people suggests pairing the K340 with tube amplifiers to add body and musicality. As amazed as I am listening to Beethoven’s Symphonies on the K340 & the Beta 22 amplifier, I know that Norah Jones isn’t going to work as well with this combination.
The high frequencies, coming out of the electret driver, trumps anything that the HD650, the K701, and the MS-Pro can produce. The strings section on an orchestra sounded sublime on the K340. Not only do you get speed and detail, but its treble is so refined without a hint of harshness and shrillness. Although the K340’s soundstage is nothing to brag about, it is instrument separation that really shines on the K340. No dynamic cans below the $1000 mark can touch the K340 on instrument separation.