Just received my Omega 2 MK2 and I had a question:

I don't think you can be sure unless you take them apart and look (or you try them on and see if they "fart"). Since the only person who is known to have a non-ported Mk2 is Clark, perhaps he can share his serial number so you can see if they are an earlier/later model.

 

To grab a reply of mine from the C-32 thread:

 

My Mk II was one of the two heard by Spritzer at CanJam 2010. I received it very shortly after it was received by a dealer from Yama's. It shipped September 9, 2009. Judging from the soap opera it took to get it from the distributor, it was probably hot off the boat from Japan. #SZ3-1383.

 

Spritzer heard the other one in the Woo room.

He noticed right away that it "farted," and he said it did not need the spring mod. So I haven't touched it.

Edited by Clarkmc2 - 1/7/11 at 10:12pm

Apparently Spritzer didn't open it to check the port.  Someone really needs to open them to see what Stax might have done.

I wouldn't worry too much if yours has the port or not,

On my 007a, which was ported, it was very easy to plug the port.

The easy way is to just cover the small holes on the black earpad plate with some blutak.

 

This way, you wont have to unscrew the earpad plate, and if you want to remove the blutak, you can simply rip off half of the earpad and just roll it off.

Stats make a sound when the air pocket between your head and the driver pushes or pulls against the diaphragm, due to a change in pressure.
It just means there is a somewhat airtight seal for the air pocket.

It kinda sounds like a popping sound for the O2, and the lambda's made a squeeky sound.

If you break the seal you get a silly amount of mid bass, and a loss of deep bass.
And that's more or less what the port did to the O2mk2.

The fart is very obvious, if you lightly push the cups towards your ears, you should hear it.
If you don't hear it, it has the port or you need to rotate the earpads for a better seal.

You are quite a ways away from me...   No amount of tweaking will make a Mk2/A into a Mk1 as the drivers are slightly different to these ears.  Slightly more forward but in no way inferior, just different.  I haven't opened up a SZ3 version (not that Stax serial number have ever meant something in the past) but if somebody has a used set they want to sell, drop me a PM.  I'd love to rip it open and see what Stax have done. 

 

The spring mod eliminates some mild midrange etch which is present in the Mk2/A but not in the Mk1.  My audition of the Mk2's at CanJam was too brief to fully establish is this was needed or not.  The spring which holds the earpads in place on the newer model is quite a bit different from the Mk1.  Stax probably received complaints that the cups were to shallow so users with protruding ears couldn't get a comfortable fit.  Their solution was to increase the height of the earpads but that is a terrible idea when it comes to planars.  The solution is quite simple, make the spirng sit closer to the backing plate and make it slightly larger so it grips the sides of the earpads and isn't just sitting in the middle. 

 

If you want to read up on this, just google "sr-007a port mod"...