And of course there's the issue of whether you really want to walk around like this:

The Source it is!

A 3.5mm stereo male to dual 3.5mm stereo female adapter would be smaller. Plus, you'd, uh, be ready to share you're audio with a friend. Yeah.

Funny how this came up, I am, at this time, working on creating an adapter so I can use a variety of headsets and microphones with my N900, PC, radios (I'm a ham radio operator), etc.

Today I bought a a pair of 3.5mm TRRS plugs for only a couple of bucks each from a local store (living in Phoenix makes this kinda easy). Now it's just a matter of getting some 4-wire cable (I ran out of time in that store before I had to go to work) and other connectors to do the job on the other end (one of which is proving very hard to find locally and/or cheaply). FWIW, there's no need to have the ridiculously long cable above if you can solder a bit.

One other idea I had (now out the window since I bought the 2 TRRS plugs) was using the N900's TV cable and just connecting the yellow video connector to a mic via another cable with RCA plugs on one end and the necessary jack on the other. There's no reason why this won't work with other people's projects, though.

BTW, that leaves a question: I still haven't read anywhere whether there is phantom voltage on the mic line to power an electret (condenser) mic. Both of the mics I want to use are dynamic so I'm wondering if this will create issues. Also I do not know the impedances of either the N900's output or my new headset's earphones...

If you do make one work for the N900, i'd be happy to buy one

I'm sure there are a bunch of better options (the above, only if you can get a compact Y-cable version - there are monolithic adapters of that sort available but obviously you'd end up with a giant plug stuck in the phone socket) but it comes down to what he can readily buy I guess.

I still vote for a headPHONE.

Im voting money;(

Well, put it this way - you can get a usable headphone better than most stuff they'd integrate into headSETs for little more than an adapter in many places.

Since you mentioned The Source, I assume you're... Eh.

Shopbot.ca has this source for the KSC75 for example, a popular on-ear-clip phone for audiophiles on extreme (ly low) budgets. http://www.ncix.com/products/index.p...2&promoid=1276

Sorry to be necrobumping here, but I bought the latest Koss Korta Pro model, and the same problem arises. Terrible noise plugging it all the way in. I was wondering, these TRRS-->TRRS adapters out there should work right?
Up to now I have found this one that seems to be the deal:
http://www.meelec.com/MEElectronic_T...tr-trrs-35.htm

But, interestingly enough there is one at DX.com too, but can anyone confirm that this should do the right remapping of the TRRS pin?

http://dx.com/p/3-5mm-4-conductor-tr...r-5-pcs-174101

I bought the damned headphones just because it HAD the mic, thought it would be a nice addition. See, my old koss porta pro finally broke.

I want to use the mic in them.
Would this work with the DX.com adapter? Or the first one?

Ah, never mind! My wife had a very short cable she had found just laying around at her work. I remember examining it and saw it was a 3.5mm female to 3.5mm male. I remember that I was thinknig "wow, this is the invention of the century, who would want this stupid thing? Extend your cable by 10cm?" I gave it to my little daughter to play with.

Now I know: Dammit, its a TRRS-->TRRS adapter. I tried it out and it works like a sharm. Even taking phone calls and using the mic!

There's a little white plastic sticker on it showing that it was bought here in Gothenburg Sweden in the most common electronics store chain we have "Clas Ohlson".

But: This story made me loathe iPhone and apple even a little more (if that is even possible).