"Ear speaker"

[Navyblue]

I am wondering, if it is possible to build an "ear speaker" like the AKG K1000 or some of the Stax with easily obtainable FR driver?

For those not familiar, this is how AKG K1000 look like.



It is basically open baffle full range speakers. You can call it "super near field listening" if you like.

It doesn't have to be that small or sleek. But to keep the weight and size reasonable, it can not have a speaker box. The question is, can the full range drivers out there achieve a decent frequency response when used like this? I imagine bass would be a problem, the K1000 above is reputed to be light in bass.

I'd appreciate if you guys can point me in the right direction on which drivers to look into, hopefully something affordable.

[nattonrice]

There are two distinct versions of the k1k: bass light and bass heavy.
Having heard both (and having a heavy version sitting here at my feet) I can tell you that the bass heavy pack a real punch in the low end of things.

I'd be very interested in a miniature fr with similar capabilities to the drivers in these.

[pHirenze]

Is the K1k FR or multi-way? Could you approximate the size of the drivers used in it. I tried to google pictures, but it's hard to see through that mesh.

[qusp]

its fullrange, as mentioned above...twice =)

Nattonrice, have you got winks K1K on loan?

its true its not uncommon for people to run a fullsize sub while listening to these to augment bass. pretty special headphones (if somewhat whack to look at)

[Navyblue]

I have no info on the exact driver size, But from the look of it, it looks like 1-2" (2.5-5 cm)

6moons audio reviews: Stefan AudioArt hard-wired AKG K-1000

Towards the bottom of the page, you can see a simple circuit. Anyone has a clue on what it is? Low pass filter?

[pHirenze]

Oh sorry, how could I miss that!

I once had a pair of W3-871s' breaking in on baffles made out of covers of empty CD stacks (basically plastic 13cm diameter 10cm long tube with a driver at one end stuffed tightly with natural wool). I listened to them "extreme near field" one night, because everyone else were sleeping. I was really amazed how low those went when held just a few cm away. That got me basically the same idea of design. Those massive shielded 3-inchers are not the type of driver you'd want for this kind of application tho, so I experimented with little 1-2" pc speaker drivers in cardboard and plastic baffles to get an idea of the problems and limits of the concept. I was most worried about the back wave traversal time issue similar to open baffle, but when the driver is that close, it's really different.

If I'd try this with real applications in mind I'd look for 1-2,5" lightweight fullrangers with relatively small magnet size to Sd ratio that could handle the lowest point of your chosen bandwidth.

[pHirenze]

Can't really see the whole wiring, but there's an inductor and a capacitor and a resistor in parallel, so I'd bet it's something more complicated than just LP/HP (i think HP is what you meant).

[cotdt]

It's an easy project with a 2" fullrange. You can put the passive network in a box instead of inside the earspeakers. I'm surprised no one has tried it.

[Osvaldo de Banfield]

Yeah!. I tryied a pair of 15" speakers, but the people around me get very angry .

[nattonrice]

Originally Posted by qusp

Nattonrice, have you got winks K1K on loan?

Nope I got Justin's.
I think Wink has both versions for memory.