When you say USB, do you have a turntable with a USB output?
I can't help you with "best"... (I've never had an unlimited budget.)
The biggest factor is NOISE. So, I'd say use the set-up with the best signal-to-noise ratio. Your RIAA preamp is probably the biggest noise generator, followed by your soundcard. (A USB turntable has both an RIAA preamp and "soundcard" built-in.)
My "standard comments" about LP recording...
QUOTE ("DVDdoug")
There is lots of information about LP to DC transfer on
this web site (Clive's website).
I will almost always do the following:
I always
check for clipping. (I simply check the peak level, and if it's 0dB I assume it's clipped and I re-record.)
I use
Wave Repair (Clive's software) to
remove "ticks", "clicks", and "pops". It does an amazing job by replacing the defect with the just-preceding or just-following few milliseconds of sound (or a couple of other methods). WARNING - This can be very time consuming. Wave Repair seems to work best when used manually. It usually takes a day (or a weekend) for me to fix-up an LP.
I
try some
noise reduction and/or
noisegate. Sometimes there can be artifacts (side effects), so I don't always apply these "filters".
If it's an old "dull sounding" recording, I'll add some high-end boost.
After I'm done with any other processing, I always
normalize (or GoldWave's
MaxMatch). This sets the level so that the peaks are exactly 0dB, giving the best signal-to-noise ratio at playback time. It's generally best to normalize the whole album as a single WAV file to retain the
relative level between the tracks... Some songs are
supposed to be louder or softer than others.
Whenever I burn a CD, I always
make an extra archive/back-up copy. If I'm doing lots of processing, I make an un-processed archive CD too.
P.S.I forgot my most important piece of advice...
Don't do it, unless the CD is unavailable! My vinyl transfers almost never end-up quite "CD quality". I'm sure there are exceptions, especially if you have a pristine LP and if the only CD available is an over-compressed remaster... But, last time I was doing this... I was almost done when I found an out-of-print used CD copy, and I bought it!