Best significant upgrade? Dac? Preamp?


Hi guys!

Im hoping some of you with knowledge of my system can help me make a good decision about my next upgrade.
I would like a surprising and obvious difference not hard to spot subtle change.
From my research i think the next move should be the Dac.
I would like to explore DSD,i have some SACDs now.
my system:
Mark Levinson 320s preamp
(Would i see a difference with a ML no.52?) I am also looking at the no.52 ,would i see a big difference compared to the 320s? Worth the extra $$ ?
interconnects: Acoustic Research master series silver high definition RG6
ML 431 amp
XLR: +bo ? +ba ? Only info on them

Wilson Audio Watt Puppy 5.1 speakers (serie 7 tweeters) +transparent music wave plus cables
Arcam rdac (wifi) with Teddy Pardo power supply.
Running on mac air (usb) ,Tidal HIFI
(i currently listen most of the time to this vs rarely SACD).
Thanks!



128x128nicsaudio
The PS Audio Direct Stream DAC is supposed to be amazing.  I have the previous incarnation, the Perfect Wave DAC mk II and it is outstanding. From what I am told, the DSD version is a significant upgrade.  Either of these units is a big step up from the Arcam model you have now.
Without question a dac upgrade.  I also don't see any reference to ac power isolation/conditioning. Any?
How much are you interested in spending? (I have no industry affiliations :) Pete
Get a tube amplifier. Something like a VAC 300.1 or VAC Phi 200. Or perhaps one of the big boys from VTL or BAT.