Need JAN 6418 tube stereo headphone preamp kit advice!

[Audiological]

Hello all,

So, I purchased the K272a kit from Oatley Electronics and it arrived yesterday. I have yet to start building because I am wondering if there is anything I can do to improve this kit prior to build. I also have been reading on numerous forums that this kit is far better suited for 32-64 Ohm headphones. At the moment, I was intending on using two sets of Koss headphones and possibly a set of noise cancelling Sony's.

The first Koss headphone is a Pro 4AA @ 250 Ohms. I am not sure of the second set of Koss circumaural headphones because they simply do not have any markings on them as to what the model is (if anyone can assist in identifying these, that would be great). At this point, I really do not want to use the sony ones because they are uncomfortable.

Here is my question: am I going to need to change out/upgrade any of the parts to account for the large jump in the Ohm rating of my headphones? Are there any recommended upgrades/mods for this kit?

This is my first electronics Hi-Fi kit build, but I am ready to get going!

Many thanks!
-J

Edit: The second set of Koss headphones are the Koss Solo 32 Ohm. Google image search is a wonderful thing! Also, the Sony headphones are Model MDR-NC7 @33-35 Ohms (depending on the status of the noise cancellation.)

Thanks.