Streamer/server newbie

Hello everyone, I never felt I would consider purchasing a streamer/server yet here I am and I blame talking to another audiophile after he asked ‘what’s new with your stereo’ and told me about his recent streamer purchase. From peeking at these units I’m interested in the Aurender’s, Lumin’s and maybe Naim.  I do not want an integrated DAC. My system; PBN mono amps, PBN preamp, PBN M2!5 speakers and a Bel Canto DAC 3.7 with Reference upgrade and most likely in near future upgrade to a Lampizator DAC. Budget to match the system so $5k more or less. I do not foresee me abandoning CD’s for an all digital download library however I’d like to be able to have the ability to download  music. Thanks for any and all suggestions.