Recording - March 2014 - 24

Reviews by Mike Metlay
Of all the headphone reviews I'm doing for this issue, this one's
the toughest, because I have to balance attention to three very different new headphones from AKG. The K612 PRO brings a previously unthinkable level of listening quality to a price point that's
reachable by any serious recording musician; the K712 PRO takes
an existing headphone design that's already won rave reviews all
over the world and makes it available to a wider audience than
before; and the K812... well, let's not get ahead of ourselves, okay?
We have been reviewing the AKG K Series headphones for
many years now; there are certain K models that have entered the
history books. I frequently turn to AKG's closed-back K271 Studio
phones for my work, and I still have and use a pair of AKG K240
M phones, a fixture in orchestral recording sessions for decades,
that have been with me for a quarter century.

a gold-plated TRS miniplug with screw-on 1/4" adapter, connects to the left earcup and is not detachable.
The K612 PRO has a 120 ohm impedance and therefore
wants a bit more power in a headphone amplifier than phones
with a lower impedance need to get really loud; it will be fine
with any professional console or audio interface, but might not
get to the levels you want to hear if you hook it up to an iPod or
smartphone. Its sensitivity of 101 dB/mW means that it will have
good transient response when properly driven. Its frequency
response is a far more than respectable 12 Hz to 39.5 kHz.
My first impression of the K612 PRO was of an expansive,
detailed, balanced space in which I could live with the music.
I could pick out individual instruments easily and home in on
details like pick noise on guitars, sibilance in vocals, reverb on
guitar amps, and more. While it's possible to listen to a mix as
a coherent whole on these phones, the tendency is to hear
almost an exploded view of a track with each of its component
parts represented clearly. When a mix makes too much use of
stereo effects that smear sources across the whole sound field,
the overall effect is to produce a sort of dimensionless flatness,
and the K612 PRO reveals those excesses instantly.
The frequency response of the K612 PRO sounds almost clinically flat; sources are clearly heard in the soundstage but there's
no particular emphasis of bass over mids or treble over bass. It's
easy to make accurate use of EQ for surgical adjustment or
broad tonal shaping, as the K612 PRO lets you hear precisely
what you're doing to each track. The overall sense is that there
isn't a frequency curve to speak of; it speaks by its absence.

AKG K612 PRO, K712 PRO, and K812
Pure listening joy, in your choice of excellent, phenomenal... or Oh My Gosh
Keep an open mind
Some engineers prefer open-back headphones because a sealed earcup can have a
strong effect on the tonality of audio heard
through the headphone, especially in the bass.
Open designs are considered by many to give
the most accurate listening experience possible
on headphones, but they're not suitable for use
near open mics because there's no isolation of
what the listener is hearing in the phones.
The overall experience of a good open-back
headphone can be a revelation; the soundstage seems to extend well beyond the user's
head, providing a virtual stereo field where
individual sources tend to sit with an accurate
and reproducible pan position. While my own
studio space favors the use of closed-back
headphones due to their isolation, I love the
sound of open-back phones when I can get
away with it, and I was looking forward to
hearing these three new models.
The K612 PRO
I'm not sure if the K612 PRO is the most
affordable open-back AKG headphone ever, but certainly no openback AKG has ever delivered this much quality at this price. It's a circumaural design with large, airy cups that seem to float on the ears.
The earcups are supported by a spring-loaded leather headband
that adjusts precisely to the size and shape of your head simply by
putting the headphones on, a feature that's long been an ergonomic plus for AKG. The velour-covered foam earpads position the drivers without being obtrusive, and the headphone weighs only 238
grams (just over 8 ounces), meaning there is essentially no listener
fatigue even over hours of listening. Its 3-meter cable, terminated in
24

RECORDING March 2014

If you've never heard what a good
open-back headphone can do for your
tracking and mixing, the K612 PRO
would be a fantastic place to start. It's an
extraordinary introduction to the sonic
pictures that AKG headphones can paint.

Recording - March 2014

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