K271 first impressions

[jpgerard]

Hi there,

I just plugged in my new 271 and here's what I heard;

Good sensitivity, almost too much for me since I'm used to the 240M!

The switch is handy and works well.

COMFORTABLE INDEED! Almost as good as the 240 family.

The balance is pretty amazing for a circumaural closed back set. And the overal sound of the 240M is there! the midrange is smooth, the highs defined and clear, and like the 240m, the 271 enhances sybillance a nitch. BUT...
The 271 low end is muddier; the 240M remains king of LF definition AFAIAC.
WORSE is that the L driver sounds like its LF peak is lower than the R driver! But it's a minor problem. Let's keep in mind that thies are sealed cup headphones.
I tried the "mod" from the Head-Fi forum, and I don't like it. Instead of knowing where the problem is, it actually blurs/hides the problem and the low end doesn't sound the way it should (well, even less.).
The top end sounds a bit different but I didn't spend too much time with the mod and decided to go back to "stock".

I decided to burn them in a few hours and see what happens.
So far Im' thrilled that I've found a closed back set that comes so close to the 240M. Even the soundstage well represented.
After the 171, it's a pleasure: a lot more linear, smooth and relaxed, but they can't be used with musicians who want a "smiley curve" response and move their heads a lot: that's where the 171 comes in!

More 171/271 comparisons soon.

First let's see if a good burn in solves the funky 271 LF.

JP

[jpgerard]

Hmmm... after many hours, there's a change. I don't know if it's supposed to happen. But... I left the cans on continuously for 11 hours friday and another 5 today with a healthy dose of music and the low end did indeed stabilise a bit, but there's still a slight L/R mismatch. i swapped pads, didn't change a thing. My 140m, 240m, 171 sets have perfect stereo spread, but the 271 has that low end that's slightly shifted towards the left cup (the one with the cable).
Again, it's VERY subtle. No real point of concern, although mono sources appear slightly to the left.
I wonder if it's because the L & R elements aren't closely matched enough in terms of sensitivity? I'll test the resistance and see if there's something weird.

Otherwise, what a sound! Very close to 240m, but closed back of course. These will be used a lot. I'll test drive another set and if the funky lows aren't there, I guess I was just un-lucky with this pair; but assuming the LF "problem" is case specific and not a regular occurence, I'll get another set for sure.

JP

[jpgerard]

Yep, there's a +/- 2 Ohm difference between drivers!
Not sure it's the cause of the problem...
If anyone at AKG could shed some light on this...

Hopefuly the difference in sound will keep slowly disappearing.

I love them though, they're by far the best closed backs I've tried...
AND they're comfortable.

JP

[Michael Yoder]

jp,

Did you buy your K271 from a retailer with a sensible returns policy?  If so, ask them to swap you another pair to see if in fact you have a defective unit.

Maybe AKG will provide a comment as to whether or not the unequal bass response between the L and R sides is atypical??

Thanks for the reviews thus far.

Cheers,
Michael Y.

[jpgerard]

Hi Michael!

Well... I gave up buying equipment in my country (Belgium) and I order mainly from Germany now; sending the cans and waiting for another pair... which will probably have the same "problem"...  nah.
I tested my other cans, and a few Ohms between drivers seems a normal tolerance. The 171 are similar to the 271. And of course for 600 Ohms models, who cares?

Some more listening tests revealed that the "problem" was slowly going away; perhaps the diaphragms settling down? I don't know. It also varies with the HP amp used! I double checked everything, from wiring to cup seal. Actually I noticed that the 271 are more critical when it comes to positionning than all my other 'phones. Reminds me a bit of my "old" another competitor 265 I sold a few weeks back. A slight movement and the whole timbre would change! AND, I'm a mid-long hair hippy so that doesn't help.

At this point, the subtle difference is almost non existent. Very weird.
I'll post again if the problem comes back, and will then look for a solution.

JP

[jpgerard]

Hi Michael!

Well... I gave up buying equipment in my country (Belgium) and I order mainly from Germany now; sending the cans and waiting for another pair... which will probably have the same "problem"...  nah.
I tested my other cans, and a few Ohms between drivers seems a normal tolerance. The 171 are similar to the 271. And of course for 600 Ohms models, who cares?

Some more listening tests revealed that the "problem" was slowly going away; perhaps the diaphragms settling down? I don't know. It also varies with the HP amp used! I double checked everything, from wiring to cup seal. Actually I noticed that the 271 are more critical when it comes to positionning than all my other 'phones. Reminds me a bit of my "old" another competitor 265 I sold a few weeks back. A slight movement and the whole timbre would change! AND, I'm a mid-long hair hippy so that doesn't help.

At this point, the subtle difference is almost non existent. Very weird.
I'll post again if the problem comes back, and will then look for a solution.

JP

[jpgerard]

Right, some more comparisons...

The 141m is the darkest (downwards sloping HF) and meatiest (big lows-low mids).
The 171 is the most hyped on top and very-bottom ("smiley" curve).
The 240m is the most accurate. I'm in love and will buy more. I added a notch of top end to my ref. speakers and I now have the same sound everywhere. COOL!
The 271 is very similar to 240m but has a less accurate low end and a more pronounced HF response. Mids are quite similar.

The 141 and 171 have a similar, very distinct "L C R" stereo image  while the 240 and 271 are more refined, the 240 being king of the stereo field.

The 141 and 171 aren't as comfy as the 240 but clamp the head and stay in place. The 171 is more tiring due to a more aggressive freq. response.
The 271 isn't as comfy as the 240 and is a wee bit more tiring due to a more generous LF response. I could wear the 240 all day long, but would probably need a couple of breaks with the 271 ;O)

I'll add that I adjusted the head band anchors on my 240 and 271 models so that the head band has a bit less travel.
Otherwise, clients keep complaining that "they're too big!".

I'm desperately waiting for my K401; should be with me any day now.

JP

[jpgerard]

And that double post was even more scary than my funky 271 problem!!!

JP

[jpgerard]

OK, this morning the problem was still there.
So... since I'm not a big fan of lowZ headphones anyway, I increased the impedance by adding 200 Ohms in series, and counter balanced the difference with precision Rs. So, they're both exactly 255 now.
No more LF stereo image problems!

The level is now almost the same as my K240m, and the big surprise is that the low end of the 271 is still generous, but now also tight and punchy, more precise!

So if you own a K271 set and are handy with a soldering iron...

I wouldn't mind a replacement "made in Autria" translucid sticker, the original has obviously been removed a couple times too many!

JP

[Michael Yoder]

jp,

I'm assuming that AKG's warranty would include a repair (or replacement) that would result in an improved matching of the impedance between the L and R transducers, so that a novice like myself wouldn't have to make the kinds of alterations you made.  I understand the logic of what you did completely, but I wouldn't know how to do that myself.  It'll be interesting to read AKG's response to this thread.

Anyway, I think I need a closed pair for two purposes:  1.) The occasional time when the bleeding of the cans into a mic might be a problem (such as when mic'ing an acoustic bass guitar, which is not a loud instrument, and requires the mic signal be turned up quite a bit), and 2.) when I want to listen to the mellowist of ECM jazz without distractions, and neighbors have their loud lawn mowers or leaf blowers going or are slamming the doors of their giant sports utility vehicles (EVERYBODY but me, it seems, has those dangerous eye-sores here in Texas).  Comfort matters, but the sound is most important.  I love my K-401's but they allow too much ambient noise in, and are hard to drive with a portable CD player (they even cause the Headroom Air Head to distort quite easily.)  The K240S has become my all-purpose phones now: for studio and general listening.  I take it you would recommend the K271 over the K171, given my love of the K240 sound?

So you're in Belgium??  I've always had a fascination with your country!!  Glad Belgium did so well in tennis this year.  I've been meaning to travel there to look over the urban geography and industrialisation of Li?ge, and nearby Maastricht (I'm a geography professor/researcher by trade).  I would need to find a grant to get me there, however.

Cheers,
Michael Yoder

[jpgerard]

Michael,

I'm sure that if I'd called and got a RA N? from AKG, all would've been well! I just figured, well, might as well try a quick fix.

Re: 1) The 271 will work just fine.
Re: 2) The 271 is a fine set, but very loud outside sources will come through. So don't expect a complete sonic void. But they do offer good iso.

Since you really like the 240, the 271 will be more to your liking. almost as comfortable, and as I mentionned, it gets close to the sound of the 240. Th elow end isn't as precise, but it is a closed-back model!

Funny you should mention Li?ge, I'm about a 15mn car drive away from Li?ge... Plenty of stuff to see in Wallonie!

If you can manage to come to Belgium, Email me jpgerard@advalvas.be and I'll show yuo my studio!

JP

[arush]

JP
u mentioned the isolation factor of the K 271's.

I'm a drummer, and have my set miked, so i need some isolation headphones to protect my hearing. Will the 271's isolate me from my drums without having to pump up the volume which would damage my ears even further?

thanks

[jpgerard]

Yes, but the K171 will probably be better suited, although they're a lot more coloured: too much top end bottom end emphasis for me, but most drummers who come to my studio love the 171.

Otherwise, the Beyer 100 family would be nice too, but I find them WAY too woofy.

Try the K171s, if you don't like the way they fit, thejn try the K271s.

You could of course try ear plugs + the K171S, it works well, I've done this a few times!

JP