Total newbie question here about completing a system

Much thanks for all...this has given me a good next step in my understanding. I'll circle back with more info on the TT, but in the meantime I'm intrigued by Willemj's suggestion of "the very good and very affordable ODAC"... I'm a little unclear about the model.. Is this it? https://www.amazon.com/FiiO-E10K-Headphone-Amplifier-Black/dp/B00LP3AMC2/ref=sr_1_1?ie=UTF8&qid=1514410871&sr=8-1&keywords=ODAC
And can I assume you simply connect this to a USB port on your computer, then attach cables from line out on this unit to line in on the preamp?

https://www.amazon.com/JDSLABS-ODAC-Digital-Analog-Converter/dp/B00EJ9N8U2/ref=cm_cr_arp_d_product_top?ie=UTF8

The one you linked to looks fine to start with. You'll need a 2.5mm to RCA cable to connect these DACs to the LS2.

The one the OP linked to is not the ODAC but a FIIO. The ODAC is a now legendary design by an anonymous experienced engineer called NWavguy (you can google him and his description of the design process, plus measurement data) who was fed up by expensive snake oil products and designed an affordable usb dac that really is about as good as the best. It is available from different sources and with different cases.See e.g. here: https://www.jdslabs.com/products/46/standalone-odac-rev-b/
The one I bought is from Mayflower and sells for $119: https://mayflowerelectronics.com/odac-rev-b-stand-alone/
It is a basic usb DAC: you connect it to the usb port of the computer, and you connect the output to the line input of the amplifier. You normally do not need any specific drivers on the computer. Output is 2.0 Volt, just like a standard CD player. It takes its electrical power from the usb port, so no further cables are required. And it is a tiny and discreet box, smaller than a cigarette case.

thanks for this...we'll pick up the ODAC as a start.

The turntable/cartridge combo is from an old kit and is nothing special -- Yamaha Stereo Turntable TT-300U3, cardridge -- Audio Tecnica VS245LP

Would love recommendations on a phono amp.

As for cables, can I assume the normal Monoprice cables are good enough?

A Pro-Ject Phono Box would be a good place to start: ($100)
https://www.amazon.com/Pro-Ject-Audio-Phono-preamp-output/dp/B007DB5I60/ref=sr_1_8?ie=UTF8&qid=1...

...or I have a friend with a cambridge cp-1 he's been happy with as a budget phono amp: ($150)
https://www.cambridgeaudio.com/usa/en/products/hifi/phono-stages/cp1

...or if you or he likes puns, people tend to love Schiit Audio equipment and they make a phono preamp. I haven't heard it myself, but their stuff is usually very good for the money and includes decent warranty and return policies: ($130)
https://www.amazon.com/Pro-Ject-Audio-Phono-preamp-output/dp/B007DB5I60/ref=sr_1_8?ie=UTF8&qid=1...


Cables are a huge debate on these forums, but I'm of the opinion that so long as your cables aren't broken or damaged, they're almost never the weakest link in the chain. I'd get these interconnects:
https://www.monoprice.com/product?p_id=5346
and I'd spring for speaker wire with banana plugs already attached just to make your life easier. Something like these:
https://www.monoprice.com/product?p_id=13913

Best of luck and enjoy the music!