The most recent Fundamentals of Digital Audio podcast includes a segment on trying to digitize vinyl records using an Edirol interface and a borrowed turntable. Geoff, the host, gets mixed results, since the files he has in the end sound harsh, bright, and noisy. Here’s why.

You really need a proper phono preamp to do this sort of thing, for three reasons:

1. It will boost the signal so you can get as much fidelity as you can.
2. The ground wire screw that phono preamps usually provide will help avoid static and interference, further reducing noise.
3. The preamp will apply proper RIAA equalization curves to the signal. Yes, before the RIAA was the Evil Empire, they were primarily about establishing technical recording standards.

#1 and #2 are the main reason the recordings were noisy: boosting signals artificially in Bias Peak is really only stretching signals that aren’t using enough of the digital bandwidth, and it’s much better to get a hot signal from your record player to start with.

#3 is the main reason the recordings were harsh and bright: the RIAA curve was established because really bass-heavy recordings tended to send phono needles skipping right out of the grooves, so the bass frequencies were rolled down for record pressing, then boosted back up in the preamps of phono players.

So if you don’t have a receiver with phono inputs?

• Borrow a stereo receiver that has a phono preamp with ground screw. If it has both phono inputs and RCA outputs, you’re good, because it will send out a line-level signal to your computer.
  – OR –
• Get yourself one of the many phono-available interfaces out there. Some USB and FireWire interfaces also offer phono inputs, but they’re expensive. A dedicated phono preamp should only run you about $50.

Your sound will be so much better you won’t believe it. Indeed, it’s true that re-buying on CD or in iTunes may be more cost effective—but if you have records that are out of print or otherwise hard to find, doing the audio work may be worth the effort. Some software, such as Griffin’s Final Vinyl or Roxio’s CD Spin Doctor, can help you automate the process somewhat.