[SWIN]

As an owner of AKG 340 since new, I have found that every piece of hifi equipment with a phone socket, is unsuitable for the AKG 340 phones.

As an example, a CD player usually use a small IC, with an equally small power supply - not enough to power the AKG 340's.

And, most, if not all amplifiers that have a phone socket, also have some resistors between the socket, and the usual speaker output.
The problem with those resistors is, that they usually messes up the frequency response of the AKG's.

The only solution is, to make an adapter, and connect the phones directly to the speaker outputs.

/SWIN

 

[vid]

I'd say the loss of definition on the K 340 can't be fixed with a speaker amp, but would love to see measurements.

 

[TimSchirmer]

Mine look like a metallic mirror color on the inside but I do see some possibly greenish metallic hues in there. I agree about them needing a lot of power. My Yarland P100 seems to get them loud enough. I'm sure if I plugged in some Grados at the same setting I'd blow them out.
 
If you need something portable that can drive them, the Geek Out 1000 did an okay job of that. I actually like these cans so much that I returned my Grado GS1000's and am using these as my primary cans now.

 

[Claritas]

Mine have the green drivers. I bought a tube amp for it because the electret treble needs filling out and smoothing down. It sounds pretty good out of Vali too. When people ask what other phone it sounds like, I tell them RS1.

 

[vid]

For my K 340, I found that velour pads increased treble fidelity over pleathers in terms of neutrality and smoothness/speed of decay.

 

[Claritas]

For my K 340, I found that velour pads increased treble fidelity over pleathers in terms of neutrality and smoothness/speed of decay.

Where can you buy them? Are they the same as the K240/271 pads?

 

[vid]

They were the normal K 240 velours, bought from Thomann. It's a tight fit, though.

 

[daltonlanny]

Does anyone else besides Thomann sell velour earpads that will fit the AKG K340?

 

[ddd777]

You can find velour pads on ebay - look for pads for AKG k240 or AKG k271 - they will fit: its a tight fit, but I had them and it was ok.
I prefer pleather, however.

 

[AdamTR]

Like the vintage look of it, anyone knows which year they originally came out?
 

 

[ddd777]

  Like the vintage look of it, anyone knows which year they originally came out?
 

I think it was 1977 or 1978.
And they sound much better than they look.
After I got my NOS pair, I sold within a week k702, k240sextett and k550 altogether, they are this good.
And as I read online about bass heavy or light versions and big differences between pairs, I think that it might be due to electret element fatigue - ma pair just sounded fantastic from first minute, so Im not even thinking about modding it.
Excellent and highly underrated phones at very good price point, especially when found in new or mint condition.

 

[vid]

No one has shown the electrets to suffer fatigue - just random hearsay.

 

[Bothand Nether]

So I pulled the trigger on a set of these, They still have the tag hanging from the cable, but look pretty beat up.
 
Other than the velour replacement pads from ebay,
-I won't be modding them until I get a good feel for what they sound like.
 
I am going to be using a WooAudio WA3 (1st Gen) with them,
and thought You guys Might like some of the info I've gathered so far:
 
Letting these "warm up' before attempting to dissect their audio characteristics is a good idea, apparently.
 
A good powerful amp is the most important Mod for these phones, as I understand it.
 
"A lot of different variations of the K340 exist.
The electret and dynamic drivers as well as the passive radiators
and small transformers for the electret element changed during the production run.
There were also at least two different headbands used." (Wikiphonia)
 
Green: Highpass (bass light)
Grey:  Low Pass (Bass Heavy)
Black: Neutral
 
Modding usually eliminates these subtle differences by bypassing the xover to the bass driver, as I understand it.
This may also help reduce the difference of attack that is found between the electrostatic & the dynamic transducers.
 
HERE is a link to the AKG K-340 Manual, (courtesy of preservation sound)
 
Here is the exploded view of the unit:
 

as much as I want to send these directly to Mr. Headphile for modding, 
I am going to try to exercise some restraint & wait until I've worked them into my setup.
 
I am hoping my WA3 will be enough power for them.
 
I am eternally grateful for all of the information & opinions You folx have provided,
I'm pretty sure I won't be needing any other set of cans.
 
(yeahright)
 

 

[ddd777]

Well matched amplifier is more important for k340 than any of the mods...
Your WA3 might work the treat, as it is of very similar construction to mine: SET, OTL, class A, just uses different type of tubes - hopefuly it will be great pairing with k340 for you.
I use Consonance and couldn't be happier. Also, as it is a tube amplifier, different tube variants change heavily k340 response, so you can adjust how much resolution/softness/bass/mids/alts you need.
After numerous trials I think I found best sound for classical music, which is the most nautral, life-like and with haunting realism, especially when it comes to violins, cello, piano and human voices.
My setup for classical music looks as follow: computer with foobar->Gustard U12 usb interface through ASIO->Denon DVD5000 as a DAC (4 x pcm1704)->Consonance amplifier with 2xPsvanes el84+1xAmperex12au7->akg k340 without any mods at all and with pleather pads.
Never before I heard chamber music being so realistic or vocal lines so interesting. Now with k340, finally I listen to music, not to set of separate notes.
Also, Gustard u12 further imrpoved scene imaging, and although it took slight amount of "meat" away, it gave extra wideness, precision and 3D to the sound. My dac using pcm1704 also helps to deliver analogue, pleasent, vinyl-like sound, and psvanes with amperex are match made in heaven, as they greatly improve resolution, dynamism and give open, airy sound and instruments you can nearly touch.
 
I think that finding synergy with the rest of equipment is more important than modding headphones, especially that there is no need for any of the mods once you find your own sweet spot. And after trying different pads I ended up with pleather ones again - they sound best in current setup.
 
And yes, I sold all other headphones once I found my sweet spot with k340 and currently I consider this setup as a kind of end-game for me.
 

 

[Bothand Nether]

My 340s arrived last week & I couldn't be happier.
 
I really love these 340s, I am very pleased that the ebay photos of them did not do them justice.
They appear to have not been used at all, even the the pleather is perfect.
 
I wonder if the people that got theirs new in box had that tag on them.
 
I can only compare them to My vintage 240s, My Q701s and a set of HD250s.
They are fuller, especially in the lower mids, & the treble is crystal clear.
They are heavier, but more comfortable,very 70's feel to them.
They will not distort at all from the 4 output sources on my desk;
Eleven Rack HP Amp, Kemper KPA HP Amp, Behringer HP Amp or the WA3+.
 
I see no reason to mod headphones these at the moment, other than velour pads, elastics and a headband pad.
 
I checked the driver & it is the green "Bass Light" driver,
but believe me when I say that these are not bass light in any way.
Maybe even a tad bit heavy in the lower mids,
-but I'm going to roll tubes to see if that changes things much.
 
The sound is rich and full, but I feel the WA3+ may need a 5998 & the power tube mod or I may need a more powerful amp.
-It just feels like they aren't even breaking a sweat, like they want more power......
 
One of the main reasons I wanted these phones is so I can listen to my Kemper KPA Profiling Amplifier.
I actually like the sound in these 340s better than My near-field reference monitors for this,
- but I really do think they might benefit from more power.
 
The original tubes that came with the WA3+ were microphonic & weak sounding chinese ElectroHarmonix. 
I got a GEC 6080 tube & 2 matched 1970 Tesla ECC88s for 30 bucks from an audiophile in sweden.
-Much better than the tubes it came with,(but then I got it for 260.00 w/ free shipping.)
 
Pros: Big improvement in sound quality, my guitar sounds fantastic and very detailed.
Cons:I have a feeling these Headphones will weed out any inexpensive elements in My signal chain. 
 
I see a Schiit Bifrost or something like it in My near future.
 
My chain is:
Yamaha CV820WB >Kemper KPA >Frenzel Tube Preamp Sylvania >Avid Eleven Rack > Behringer Xenyx Control1 USB monitor controller > WA3+ > AKG 340