[mypasswordis]

It is indeed Headphone Madness. And amazingly, it still somehow sounds kind of good, which I find cool.

The PCBs do indeed have resistors on them. I might try replacing them with ones with less resistance, instead of completely jumpering them. I did momentarily hear the K340 without electret connected while I was modding them and although it does really only add brightness and sparkle, I could never listen to the K340 without it. I will first try damping the dynamic drivers, the poor little things. They are being helped out by the passive diaphragms so I don't feel too guilty.

That's a very fun and accurate description of its midrange. I would personally say it has slightly viscous liquidity throughout its frequency response. And are you saying you're not getting any appreciable bass from your K340? That's fascinating, because I just drive mine out of an integrated amp. I promised to write up a review for it... that'll be coming up shortly. But that's off topic.

Edit: I could also add damping to the damping of the passives.

 

[wualta]

Quote:

Originally Posted by mypasswordis The PCBs do indeed have resistors on them. I might try replacing them with ones with less resistance, instead of completely jumpering them.

I should have said temporarily jumper them, with clip leads. This was only a test to see if electret level was the problem. The ultracool DIYer installs a Bourns multiturn trimmer pot to make the treble user-adjustable with a tool, which the owner keeps tucked behind his ear.

Quote:

Originally Posted by mypasswordis I did momentarily hear the K340 without electret connected while I was modding them and although it does really only add brightness and sparkle, I could never listen to the K340 without it.

Well, of course not. We'd have to shun you if you did.

Quote:

Originally Posted by mypasswordis I will first try damping the dynamic drivers, the poor little things. They are being helped out by the passive diaphragms so I don't feel too guilty.

Are you going to press some felt over the dynamic driver's back vents? It may not take much. There's probably some factory damping in there.

Quote:

Originally Posted by mypasswordis And are you saying you're not getting any appreciable bass from your K340?

Nope, not saying that. Doesn't seem bass-heavy or bass-lite. Or bright or dull. Which I think is an indication that it's operating as it was intended to.

Quote:

Originally Posted by mypasswordis Edit: I could also add damping to the damping of the passives.

You could try the extremes: passives sealed off entirely, then with no damping. Just to see how much adjustability there is.

 

[facelvega]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif I did momentarily hear the K340 without electret connected while I was modding them and although it does really only add brightness and sparkle, I could never listen to the K340 without it.

A clean and extended top end is one of the things that separates the men from the boys in heaphonery, and the reason for all the expensive complexity of the K340 in the first place. If one can do without the electrets, he'd be better of with a Sextett.

 

[mypasswordis]

Quote:

Originally Posted by wualta I should have said temporarily jumper them, with clip leads. This was only a test to see if electret level was the problem. The ultracool DIYer installs a Bourns multiturn trimmer pot to make the treble user-adjustable with a tool, which the owner keeps tucked behind his ear.

Ah, that works, too. Also, what a great idea. If I were ultracool I'd definitely put in a trimpot, find the exact resistance I wanted, then swap in a fixed resistor. I guess I could keep it permanently tweakable, and be seen as a nutter, constantly fiddling with a pot to adjust for each individual recording.

Quote:

Originally Posted by wualta Are you going to press some felt over the dynamic driver's back vents? It may not take much. There's probably some factory damping in there.

Yeah, I think that's what I'll try first. I wonder if there is factory damping, and if it's in the plastic casing. I'm not sure how it opens, but I could probably figure it out.

Quote:

Originally Posted by wualta Nope, not saying that. Doesn't seem bass-heavy or bass-lite. Or bright or dull. Which I think is an indication that it's operating as it was intended to.

That's what I thought of my K340's bass before putting in felt. Just curious, what sort of damping arrangement/amount do you have on yours?

Quote:

Originally Posted by wualta You could try the extremes: passives sealed off entirely, then with no damping. Just to see how much adjustability there is.

I'm not sure how I would remove the factory damping, which I assume is the thin white sheets behind the actual diaphragms.

Quote:

Originally Posted by facelvega A clean and extended top end is one of the things that separates the men from the boys in heaphonery, and the reason for all the expensive complexity of the K340 in the first place. If one can do without the electrets, he'd be better of with a Sextett.

I did indeed try a middle and late production Sextett, and found both to be lacking in both treble amount and refinement. I'm glad I can be considered a man, at least by some people, and in some respects.

 

[mypasswordis]

One other thing I would like to improve with the K340 is the texture of instruments. Anyone have any idea how I would go about doing that? Perhaps that would be solved with better damping of the housing. I might have to go for something Extreme (of the Dynamat variety).

 

[joe_seattle]

Gary can tell you that I am a die-hard vocals fan when it comes to music...and I gotta say that the K340 sounded un-freakin-believable for vocals when hooked into his amp setup. Now, I'm no headphone expert by any means, and there are lots and lots of headphones and amps that I haven't tried, but to my ears the K340 hit it perfectly with vocals: forward, present, detailed, natural and warm.

Good advice I received a while back was "listen to what moves you," and vocals on the K340 do just that. Stairway to Heaven had delicacy and nuanced sound where/when it was needed and full-on slamming bass where it should be.

My dilemma now: do I keep the K340 or the HD600 (that I just received). I really shouldn't keep both...and I'd rather drop one and invest the money in a great amp for the other. The HD600 is definitely singing to me, but its ever, ever so slightly recessed mid-range is leaving me wanting. On the other hand, the bass is fantastic and the slightly dark, laid-back sound is addictive.

Thoughts on this?

-Joe

 

[mypasswordis]

You haven't mentioned anything about the flaws you see in the K340.

That said, just looking at it from a practical point of view, the K340 has been discontinued for nearly 30 years while the HD600... hasn't. Also, I think I read that your K340 isn't completely stock, so if that hits the spot, you may or may not like another completely stock pair.

Oh, and sorry about hijacking your thread.

Edit: Reading your sig, it seems you also want a bit more highs. I'm trying to figure out a good, simple mod to bring them up a bit, so if you're going to keep the K340, stay tuned. I'm not sure what to say about shrillness since the K340 is almost never shrill for me, but damping could help.

 

[Zorander]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif Edit: Reading your sig, it seems you also want a bit more highs. I'm trying to figure out a good, simple mod to bring them up a bit, so if you're going to keep the K340, stay tuned. I'm not sure what to say about shrillness since the K340 is almost never shrill for me, but damping could help.

That depends on the electrets as well. I have gone through a number of K340s whose electrets exhibit different energy levels (in addition to the dynamic driver being bass-light, -normal or -heavy). It sounds like the OP got a pair with electrets that are still 'strong'.

 

[facelvega]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif I'm glad I can be considered a man, at least by some people, and in some respects.

I was actually thinking of the headphones themselves as men or boys, or maybe the engineers who made them. Around here, maybe willingness to open up the headphone and tweak it counts in the same way, so you still get macho cred (from some people, in some respects, naturally)

Quote:

Originally Posted by Zorander /img/forum/go_quote.gif That depends on the electrets as well. I have gone through a number of K340s whose electrets exhibit different energy levels (in addition to the dynamic driver being bass-light, -normal or -heavy). It sounds like the OP got a pair with electrets that are still 'strong'.

This leads into a really worrying thing about the K340: lots of old electrets and electrostats have slowly developed a channel imbalance. It's easy to make up for this with the balance knob on, say, an old pair of Stax, but nobody has taken this into account with the many K340 mods AFAIK. A really thorough head-fier might run a signal ONLY into the electrets to test for this before trusting a candidate K340 for any extensive or expensive modifications.

 

[mypasswordis]

I'm not sure that's the case, since he said the highs were muted. I think there might be nasty resonances from the housings causing shrillness. I also remember the stock cotton damping to cause shrillness on my K340.

Also, I'm wondering if it has been proven that there were different versions of dynamic drivers put into the K340. Knowing AKG, probably, but I don't think there has been real evidence for it.

Quote:

Originally Posted by facelvega Around here, maybe willingness to open up the headphone and tweak it counts in the same way, so you still get macho cred (from some people, in some respects, naturally)

Yeah, most people would just call me a nerd.

 

[facelvega]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif s been proven that there were different versions of dynamic drivers put into the K340. Knowing AKG, probably, but I don't think there has been real evidence for it.

Well, there have been a lot of versions of the DKK 32 driver capsule with different parts numbers for different headphones (2030Z0008 for the K340, 0007 for the K241, 0010 for the Sextett or K240M, etc.). I believe it's also been shown in this forum that the appearance of the capsule in different Sextett models changes visibly, at least in the color of the plastics used.

So, I think we can say that there were a great many batches and tweaks of the driver over the years, more than we are likely ever to figure out now after the fact. It's kind of annoying, though, because if they were Grado drivers, we'd have an illustrated guide of which version was which, with some commanding prices four times higher than others.

 

[pataburd]

No hurry, Joe. Give the HD600 a good listen; there will always be a market for them when you're finished.

 

[joe_seattle]

I think with a little bit of damping, the K340 will lose it shrillness, since it was diminished greatly with a proper amp. I think the Technics receiver I have is jacked-up - it does add a smidge of brightness to my other headphones, just much more noticeable with the K340, possibly because my attention is also drawn to the treble being muted/underpowered.

Anyhoo, Gary recommended the NAD 3020 amp as an inexpensive option capable of driving the K340. Anyone else have experience with it? Would it be a good, general-use amp (if there is such a thing)? My source would be my ipod, if it sounded ok, or the Denon 970 full-size CD player.