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http://www.enjoythemusic.com/superioraudio/equipment/0903/akgk1000.htm
Dal sito:
http://www.6moons.com/audioreviews/akg/k1000_1.html
World's best
dynamic headphones?
Live long enough in
America. You'll risk terminal immunity to hyperbole. For example, cross
the remote Sonoran desert and stop at any crummy no-man's diner for some
greasy chow. You're liable to order the World's Best chili
con carne with corn bread. Or, drive through Northern California and its
Garlic Capital of the World. Going an illegal 70mph, you
probably missed this wonder because it took all of 10 seconds to pass
through. So much for absolutes.
But boy do the AKG K-1000s ever compel the question of World'
Best. You wonder whether, for anything approaching sane dough versus
fanatical excess, something better exists, somewhere, somehow. No
credible reviewer should pretend to know for sure. Still, with the
wooden Sony MDR-R10 discontinued and the Grado RS-1 and Sennheiser
HD-600 in-house for direct comparison -- generally regarded as the two
best currently available dynamic headphones in the money-matters arena
-- I could make a reasonably educated guess.
How trustworthy
are memories?
I first chanced upon the AKGs during the Tigris' ascendancy at Mesa
Engineering. I needed to demonstrate the integrated's tubular headphone
output with some world-class cans at CES. I wanted something to attract
showgoers already on looks and rarity. The K-1000s fit the bill to a
dime.
Darn, I shoulda read the specs before ordering up though. At 74dB/mW
free field sensitivity, the K-1000s need far more juice than
regular headphone sockets provide. They are fitted with a 4-pin XLR
connected tail that terminates in four high-level amplifier leads. This
scheme didn't gel with my -- carefully -- hatched plans. And while
I drooled over the sound via the amp's speaker terminals,
disconnecting the speaker leads each time I wanted to demonstrate
headphones was out. Hence CES came and went and the AKGs returned to
their maker. I stuck with my wooden Grados and loved them faithfully
ever since. Still, I never forgot the K-1000's phenomenal performance.
Nor their $1,200 sticker shock.
Years passed. My hair turned gray. My hearing declined. I grabbed the
only job left under these desperate circumstances - audio reviewing.
More years passed. All my sane friends left. I turned lonely (loony?)
and relocated to 6moons.
Then headphone maniac Tyll Hertsens of HeadRoom promised to enter my
crater-ridden but rarefied low-G domicile. He suggested a Maxed-Out Home
amp and Senn 600s for the occasion. A quick perusal of his site and --
Eureka! -- I ran into my old flame, the K-1000s. Priced at 529 smackers?
A flummoxed call confirmed that this wasn't a typo or short-term
inventory dump. It's a new, radical and standing arrangement with the
supplier. Not what passage of time and inflation usually implies.
Aural fantasies of past lusty transgressions die hard. Could he include
a pair with his shipment? Affirmative. Would the past-meets-now
encounter equalize expectations? $529 puts the K-1000s center of the
range between the Senn's $449 and Grado's $695. It would make for a
reasonably balanced peaches vs. peaches comparison (hey, none of these
are garden-variety apples or oranges - by a long shot).
To level the playing field, I asked HeadRoom
to fabricate a replacement tail for the AKGs with a standard 1/4" plug.
I had been promised a review Portal Audio Panache Integrated whose
headphone socket -- with the Ks' 120 ohm impedance -- is said to output
approximately 8 watts. I had already driven the Ks speaker-level on my
6wpc Art Audio PX-25. Its optional attenuator cranked open less than
half gave me all the loudness I could stomach. This suggested that
despite very low sensitivity -- and Tyll's skepticism that even 8 watts
would be sufficient -- perhaps less power was required than
seemed mandatory.
Being a good sport, Tyll sent out the adapter tail. The Panache hadn't
arrived yet so I plugged the new tail's 1/4" jack into Tyll's Maxed-Out
Home. I fully expected a load of hot air and not much else. Wrong!
Granted, I had to open the attenuator to between 4 and 6 o'clock, i.e.
run the amp nearly or all the way open. But even on classical CDs with
extreme dynamic range -- i.e. mid-levels recorded abnormally low -- I
never was deaf enough to require or want volume levels in excess of what
the Maxed-Out's times six voltage gain could deliver.
To boot, I had the
PX-25 and 120/360wpc Bel Canto eVo 200.4 to ascertain by comparison
whether added power delivery impacted dynamics, resolution, frequency
extremes and intelligibility. I was all set to use the AKGs in a
variety of contexts. Afterwards, I could do an even-steven comparo
between three headphones driven from the same set of electronics
despite a potential handicap for the Ks.
Ear speakers, not
headphones
Even beyond the famed Stax electrostats that pioneered the term, the
K-1000s are earspeakers, not headphones. The wire-mesh protected
transducer panels are 2.5" wide x 4.25" high x 1" thick. They're
hinge-mounted to the front of the crossbraces that hold the contact pads
and connect the two red metal frames on each side. The rear contact pad
is mounted to a slider that allows width adjustment for the most
comfortable head fitting.
Because the transducers are of the open-air design and not clamped to or
sealed around the ear, the only points of physical contact are
your temples right above the ears, and the self-adjusting head band
across the skull. The pivot for each speaker is upfront. Once you
release the lock, each panel can be rotated outwards to either parallel
your ears -- which in front are closer to the skull but splay outwards
toward the back -- or create additional airspace such that each ear
perceives yet further cross-channel data. Think of speakers-en-miniature
floating in front of your ears like the Jecklin Floats of yore - but now
toe-in's adjustable just like with "real" speakers.
Why did AKG's engineers bother? Because they
wanted to enhance binaural hearing qualities. Just as with conventional
speakers, this natural process of human hearing (duplicated in our
binocular vision) relies on each ear receiving the same
two channel information.
This parallax delivery is time-delayed due to the closer ear receiving
the information first. The time arrival differential is what the brain
processes to allocate the diverse apparent sound sources their specific
positions within a three-dimensional sound stage.
When listening to normally encoded material, conventional headphones
impose an unnaturally hard left/right/center-of-the-head effect. Each
ear only processes single-channel data. The right ear does not hear what
the left one hears, nor vice versa.
HeadRoom's well-known but proprietary crossfeed algorithm addresses this
dilemma in the electronic, AKG's engineers in the acoustical domain. The
penalties for eschewing electronic compensation is sound leakage (since
this couldn't be a sealed design - if total privacy is a must, forget it);
and low sensitivity because the free-air driver deals with far greater
air mass than is trapped within your ear canal by conventional
ear-hugging approaches. We'll soon get to the very real advantages
of AKG's crafty acoustical solution.
But first, a few final specs: Weight is <10 oz or 270 grams; total
length of the very flexible wire lead (the captured plus the
XLR-connected half with the binding posts pigtails) is a generous 13
feet; rated impedance is 120 ohms; frequency response (as per a graph in
the five-lingual manual) is 50Hz to 20KHz essentially flat within an
enviably tight -2dB overall window, and -4dB @ 40Hz, -8dB @ 30Hz, and
-20dB @ 20Hz.
As common sense predicts and these measurement confirm, free-air
dispersion causes more rapid rolloff in the bottom octave than
equivalent sealed designs. Another unusual element is the "ventilated
linear dynamic" radial NdFe magnet yoke engineered for "minimum aspect
ration and maximum flux density". The size of the dome driver appears to
be 1 inch, with a composite diaphragm of elastic intermediate layers
finished with a 16th century violin varnish to suppress ultrasonic
ringing.
Fit'n'finish and wear comfort are of the highest pedigree - think famed
Teutonic luxury cars. No undue pressure exertion onto the head.
Precision-engineered hardware tolerances. Zero chintz in sight. Shipped
in a wooden box with serial number, comprehensive owner's manual and
clear hookup instructions. In short, what you'd expect in a $1,200
headphone system.
At $529 however, it makes the now-closely priced HD-600 Sennheiser's
marbled hard-plastic construction a bit less, ahem, classy. Admittedly,
that's a "superficial" appearance comment, to be filed in the
pride-of-ownership lower drawer. But for some, it might belong into one
of the upper drawers when it comes to spending serious bread on
headphones - more on that later.
Make no mistake then - even before being hooked up, the K-1000s already
strike one as veritable class acts, samples of superior engineering with
bespoke attention to every conceivable detail. All of which amounts to
naught if the ears didn't pleasurably curl up. Not to worry ...
Setup
I connected the
HeadRoom amp to the tape-outs of my Bel Canto PRe1. Then I wired the
speaker lead tail of the AKGs to the Art Audio PX-25. By muting the
PRe1, I could cut signal to the tube amp when unplugging the AKG's
captive tail from its other half - most SET output transformers smoke
under signal without driving a load. No need to risk frying my reference
amp. However, the PRe1's tape-outs would still pass signal. By simply
hitting mute and swapping leads, I could toggle to the Maxed-Out Home
and sample the K-1000s to compare against the tube feed, then adjust
volume and compare to the Sennheisers and Grados.
The Max really came to life when I bypassed the attenuator of the
Birdland Audio Odeon-AG DAC for its undiluted full bore 2.7V RMS output
(7.68V peak-to-peak). When not used amplifier-direct but into a preamp,
the manufacturer recommends the Odeon's 3 o'clock attenuator setting. It
gives a slightly lower-than CD standard 1.5V RMS output and optimizes
impedance for preamp connection. Though the Max retained sufficient
output in this mode, the sound became somewhat thin. Feeding it a
stronger signal -- and reducing its attenuator setting instead --
significantly fleshed out the music.
The biggest difference between either hookup? Via the Max, things
sounded zippier, brighter, with a mild prominence in the upper midrange
and sharper, more highlighted outlines 'round performers. With edgier
material, this could turn slightly aggressive. The PX-25 packed harmonic
meat on those bleached bones. The presentation became far more relaxed
and full-bodied. Any former tendencies for some potential stridency
sneaking in were abolished.
Before I sketch out the sonic bliss that
follows when you kowtow to these demands, I must stress that the AKG K-1000s
are, single-mindedly, ultra performance devices. They don't suffer
casual fools lightly. Unless you treat them with the same respect you
accord your dialed-to-the-max main rig, you're better off with the
Sennheisers or Grados. The Senns up the ante in the resolution and
honesty department over the Grados and, for "normal" applications, are a
far saner recommendation than catering to these high maintenance babes.
However. For those intent on scaling the tallest peaks, the AKGs are
rare and reliable Sherpas. They image far more like real speakers,
except in reverse - the soundstage wraps around your medulla oblongata
rather than the forebrain. Stage depth is a function of how far behind
your head sounds originate This reads weird only on paper. Once you
inhale the pure air, spaciousness and freedom from typical headcase
confines, it's hard to go back. Even acoustic solo instruments now
stretch out in space rather than being locked dead center in the middle
of your skull. The ability to listen into the faintest of details,
masked by most speakers and heightened by good headphones, now operates
on a higher plateau - magnification squared.
This overall rez effect of speed, subtlety, cubits of air and fine inner
detail is similar to Stax electrostats. But here it's ballsier and more
gripping, intense in a look-how-many-stars way that night time visitors
to the high desert sanctuary of Taos always express. Like the
Avantgardes, this kind of intensity (not a tonal forwardness but simple
multiplicity of powerful sensory stimuli) isn't for the faint-of-heart
who want to drift off. It's for the thrill seekers, the adrenaline
junkies of sound orgies.
Sweaty ears, space
& matters of perspective
Take my old standby for superior female vocals, "Round Midnight" on
Carmen Lundy's XRCD release Self Portrait [0005-2, 1996]. The
Grados sounded wonderfully liquid in the mids but lacked some of the
high frequency shimmer that the Sennheisers bestowed on the sea of
violins. This created a texturally drier but timbrally warmer sound - an
apparent contradiction only if you don't refer to dryness as a textural
phenomenon.
Tonally, the Sennheisers were much closer to the AKGs than the Grados.
However, their presentation of texture differed in similar fashion to
how the 600s added air over the Grados. Now the Sennheisers stood in for
the RS-1s and the K-1000s pulled ahead. The sense of airiness and bloom
via their open-air design was in a different league. More importantly,
their sense of realism when compared to a first-rate speaker setup was
far superior. The Grados and Senns create an artificial intimacy that
lets you hear all the right sounds, but still remains divorced
from the acute realization of space, venue and perspective.
By comparison, the intimacy of the AKGs
seems the real deal. When you think about the binaural hearing
principles they exploit, this makes perfect sense (and goes far
beyond HeadRoom's electronic crossfeed). There could also be an added
psycho/physical factor at work. The Sennheisers create a little cave
that seals around your ear. The Grados rest on your ear.
The AKGs let your ears breathe freely. These differences operate already
in the tactile sensation of physical contact. Personally, I prefer the
Grado "touch" over the Sennheisers'. The latter make my ears sweat -
literally.
Such impressions are hard to separate from raw sonics. Together they
form a set of sensory inputs that combine into the total experience. And
while I appreciate the 600s' superior fidelity in terms of frequency
response, I prefer wearing and listening to the Grados. (Incidentally, a
friend of mine just sent her personal Grado RA-1 wood-body
battery-powered amplifier to throw into the ring of my current headphone/headphone
amp survey - more to follow shortly.)
On this Lundy and subsequent other tracks, the Grados conveyed more
weight and body in the bass than the Senns, quite possibly as a function
of their downshifted tonal balance. Consequently, they could be accused
of sounding slightly romantic, whereas the Sennheisers strike me as the
ideal recording monitor. Bass heft via the AKGs is somewhat adjustable -
angle the dynamic panels outwards farther to create more spaciousness
and a bigger soundstage. Swivel them in closer to emphasize foundation
weight.
The quality of bass, compared especially to the Grados, recalls sealed
versus vented alignments - very precise, tight, nimble and fast, but
with a bit less weight and mass than the RS-1s that are slightly on the
fat/warm end of the spectrum. Slap bass lines snap harder with the AKGs'
leaner demeanor while Reggae beats whomp with a heavier punching bag
clobber on the Grados.
By settling on enough physical distance to insert my index finger
between the ears and the panels' free rear edges, I obtained the most
pleasing balance for my personal tastes - between ambient cues and
airiness on one hand, and bass slam, HF shimmer and robustness (or image
density) on the other. And once I had this aspect licked, there was no
going back.
True, the K's benefited from $5K worth of world-class SET amplification.
But that's part of their twisted appeal. Being earspeakers with
high-level connections, they'll feed on the choicest signal delivery you
care to send their way. Of course I'll be the first to admit that $500
($1,200) phones driven by $5,000 amplifiers are an off-kilter
proposition. This merely reflects what I had in-house at the time.

The 4-pin XLR
juncture with speaker level leads
Hence I'm presently looking into the Antique Sound Lab offering to dig
up something more appropriately priced, say up to $1,500. True, that's
still a $2,000 package for the 'phones and amplification, but it'd be a
true SOTA rig, with the kind of superior sonics regular speaker systems
would easily charge you five to ten times for - if the rooms
cooperated. And granted, as good as the AKGs are at creating a
three-dimensional soundstage, it's not the same as via standard
speakers. But then everything else about the AKGs is far more advanced
than most room-compromised speaker setups.
So you see where I'm going. Apply the same stringent quality standards
to private listening via 'phones as you do to your beloved main rig --
and granted, not everybody takes headphone listening remotely that
serious -- and the AKG K-1000s are true cutting-edge stuff. For now, I'd
go with tubes, but likely that comment should be expanded. Perhaps the
forthcoming 47Lab Shigaraki op amp integrated, or the Portal Audio
Panache? An older Pass Labs Aleph 3 or used Volksamp?
...True
cutting-edge stuff...
Does that now make these earspeakers the world's best dynamic headphones?
I wouldn't know. What I do know is that they get my qualified nomination
for said title - if such a thing existed. And qualified -- in brief
recap -- by the need for superior ancillaries and a dedicated amplifier
that, unless you don't mind swapping leads or a switch box, will most
likely not ever also drive speakers.
Where's that leave
us?
If I can find a suitably affordable amp or preamp with copasetic
headphone capabilities that mimics the phenomenal Art Audio PX-25 hookup,
I will have to send Tyll over at HeadRoom a check for these super cans
and make an official package recommendation: For the truly dedicated
headphone fanatic wanting a top-level rig that, while dear, won't be
insanely expensive. I'll report on hits and misses of this hunt in
the saga's next chapter. Stay tuned.
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