The pono player is a best piece of hardware and its sound quality levels are so special. When you use a pono player as external DAC, then it allows the players to play multiple digital formats and also links with its own ecosystem.
If you already have the best quality of speakers, then you just need an amplifier with a preamp and it converts the weak electrical signal. The ideal preamp will always be liner and have high input impedance.
DJ controller might come with tons of confusing connections and you must understand how to connect DJ controller to speakers.