Low Cost DACs


Currently I have my laptop connected directly via 1/8 jack from headphone outlet into 2 RCAs directly into my tube amp. Quality of sound is lacking to say the least!
I am considering adding an inexpensive DAC ( iFi AUDIO nano iDSD LE Portable DAC  or iFi Audio nano iOne DAC ) into the stream between the laptop & amp.My question is: will this influence the overall sound I'll hear out of my speakers? Will adding such a DAC help to increase the quality of sound produced by the system?
I'm not interested in spending a lot of money on a DAC as this is a source that I don't use as much as some others already in the system.
wcc10
So as I stated I did order the Schiit Modi 3. Looking forward to hearing a huge difference.My next question is how are you all connecting your DACs to your laptop, Tablet, or Smart Phone? I guess obviously USB to USB is about all that is available, but are you using high cost USB cables from The Cable Company or just general cables from Staples? How much difference do you think this makes? I've played with cables over the years and yes, some cables do make some difference. But spending more than a couple of hundred dollars on interconnects is, to me, a bit ridiculous!
P.S.I also ordered a 5V i iFi AUDIO Low Noise AC/DC Power Supply to go with the Schiit.
Get an Audioquest Cinammon usb, less than $200 but still pretty good quality.  And do check out Qobuz.  For $5 more a month than Pandora, no comparison as to sound quality.
Musical fidelity v90 dac, $299, and worth every penny. Beats out dacs costing way more. Very well reviewed in stereophile and they gave it a borderline class A component rating. To be honest, all the small box components from musical fidelity are fabulous, including the lx lps phono preamp & the lx2-HPA headphone amp.