From what you say it seems the PW might be a better match to your amp.
1) Perhaps it has a better output stage than the Transporter and you are getting more dynamics?
2) If you are not using a preamp then how were you controlling the Volume with each setup? Software and digital colume control can be a bit of a minefield. The rule of thumb is to set software to MAX volume (with no processing) and to use analog controls to attenuate the sound - this helps ensures bit transparency.
Enjoy!
1) Perhaps it has a better output stage than the Transporter and you are getting more dynamics?
2) If you are not using a preamp then how were you controlling the Volume with each setup? Software and digital colume control can be a bit of a minefield. The rule of thumb is to set software to MAX volume (with no processing) and to use analog controls to attenuate the sound - this helps ensures bit transparency.
Enjoy!