Do I need a DAC

I own a Marantz SA7 CD Player with a Black Lion External clock ,Mastersound Compact 845 Amp Mastersound, PH5 Pre Amp, ART Noveau loudspeakers and a Isotec Sigma Mains Conditioner.
Would a Dac be of benefit and if so any thoughts on what to get.I have been advised Bricasti and Weiss.Rather expensive
Thanks
Patal