I've been using a USB turntable and Audacity to convert my vinyl LPs to digital files. I had been noticing that the captured files tended to sound a bit tinny. Recently, I got a fairly reliable timing sample - the album liner stated that the track was 6:30 in length, but the captured file was 6:15. "Ah!," says I! The TT is running a wee bit faster than 33-1/3 rpm! I found a tool in Audacity that slows the captured file (Effect > Change Speed) by percentage. Doing the math on the afore mentioned file times, I got a factor of ~3.85%. Processing the 6:15 file at -3.85% speed adjustment yielded a track length of 6:30 and a better sounding track/file. Now, I have to go and process quite a few tracks that I've already converted.