Question...are you planning on reclocking your USB signal between the laptop and your components input?
Lowrider, I'm not sure it is clear that as indicated in the OP's other recent thread
, his "audio interface" is providing an analog-to-digital converter, which he will be using to digitize vinyl recordings and to transfer the digital data via USB to a computer for storage. So (as you may therefore realize) reclocking would not be applicable in that situation. Once each of the analog samples is taken by the A/D converter (which generates its own conversion clock internally), the data that will be stored on the hard drive is what it is. Reclocking would only be applicable and helpful, if at all, during subsequent playback. (Although I believe the "audio interface" also includes a DAC function; perhaps the OP will clarify whether or not he intends to use that function for playback).
Toxicwaterfront, the Focusrite Scarlett 2i4 analog-to-digital converter/"audio interface" you will be using, as mentioned in that other thread, comes with a USB cable. I would use that specific cable, and whatever additional length of RCA-to-XLR cable is necessary to reach the 10 foot total.
Since the 2i4 is powered via the USB bus, if you were to substitute a longer USB cable, or possibly even a different USB cable of the same length, resistance differences in the power and ground runs within the cables could very conceivably cause the 2i4 to receive inadequate power supply voltage for proper operation.
I'll mention also that since the clock which controls the timing of A/D conversion is generated within the 2i4, as I mentioned earlier, and the timing of data transfers between the "interface" and the computer via USB is not involved in either the timing of A/D conversion or in realtime playback (assuming you are using the 2i4 just for ripping and not for playback) the quality of that cable does not have the criticality some associate with USB cables that are used to connect computers to DACs.
Finally, since you will be using the turntable's built-in phono stage, which provides a line-level output, the length of that cable will be much less critical than would usually be the case for a turntable connection.