The cable won't make any difference in sound (IMO); however, the ZX2 is quite underpowered for full sized headphones so if the pseudo-balanced output of the ZX2 provides more power then yes. Now, if you aren't using this for portable use you would be WAY better off getting any kind of amp to use with the ZX2. 15mW of output is really not very much, but to be fair the PM3 is fairly efficient but if you are like me and like louder playback levels, and have some quieter mastered material, the ZX2 is going to struggle. Don't get me wrong, I almost bought the ZX2 on a few occasions as I know how amazing it sounds, but it is the lack of any real power that stopped me. Even Sony figured that out, look at the power on their new DAPs, quite a bit higher. The ZX2 is ideal for IEM or extremely easy to drive loads. All of this just IMO, your perspective may be quite different, and equally valid.