I need advice for power cords


In my system there are 4 components that power cords are interchangeable.  They are PrimaLuna EVO 100 Tube Preamplifier, PrimaLuna EVO 100 Tube DAC, Manley Chinook phonostage and Dayton Audio sa1000 subwoofer amplifier.   Should they all be upgraded, if not all which one to change to give me the most improvements.  I can't go crazy on cost, 1k to spend.   I've followed along with many threads on this subject. Always looking to make improvements to sound quality.   Many of you have much more experience with cables than I do so what do you recommend and I can do the research.  On a side note my McIntosh MC75's are vintage so old thin manufacturer cables and probably shouldn't change them. 

Thanks 
Mike 
zardozmike
The only power cord I would buy under a k is the Transparent Audio Premium at $600.
I have the Reference on my amp and Premium on my DAC. Transparent cables are the most natural, least distorted on the market. They actually use live acoustic music as reference. The Premium on your pream and DAC will make a difference.
I really like Jena Lab power cords in my system but you could probably only get one at that price range. That stated, if I was only going to change one cord in my system, it would be the one coming from the wall to the transformer feeding the conditioners. Big impact there. If you don't have a transformer or conditioner, Mill's advice is spot on IME. 
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