No, just the Phonitor 2 is single ended, the other models offer both.
From
https://www.headphoneer.com/spl-phonitor-xe-review/
Powering Headphones
With regards to headphone performance, there is one important difference between the Phonitor 2 and the rest. The Phonitor x, xe, and e have both balanced and unbalanced outputs. The Phonitor 2 is unbalanced output only. This is quite a big deal for demanding headphones. The balanced output is roughly twice as powerful because it uses a separate power amplifier for each channel.
Other than the Phonitor 2´s lack of a balanced output, there are, according to SPL, no significant differences between the four models that affect the headphone amplifiers’ performance. All the unbalanced outputs have identical measurements.
In other words the un-balanced headphone amplifier performance of all the four Phonitors (Phonitor x, Phonitor xe, Phonitor e, and Phonitor 2) will be identical, and the balanced headphone amplifier performance of the ones with a balanced output (x, xe, and e) will be identical.