Number 223 - December 2001

Vinyl LP to Audio CD or MP3 Files
by Bruce Fries, PC Alamode, August 2001, Alamo PC Org via QBits October 2001
With a good sound recording and editing program you can take those old scratchy LPs and 78s record them through your sound card, filter out all those clicks and pops, and then burn the music to an audio CD or store it as an MP3 file. The following process also works for recording audio from other external sources, such as cassette tapes and microphones.     Use a program like CoolEdit 2000 for the PC or Peak for the Mac. Demo versions of both programs can be downloaded for free. Connect Your PC to Your Stereo     The first step is to connect an adapter cable from the tape out (or record) jack of your stereo receiver to the line input of your sound card. These cables can be purchased from most consumer electronics stores, such as Radio Shack, Best Buy and Fry's Electronics. Newer turntables with line-out jacks can be connected directly to the sound card Set the Sampling Rate and Resolution     The next step is to create a new file in the sound editing program. If you intend to create an audio CD, you must choose a sample rate of 44, 100, two channels (stereo) and a resolution of 16 bits. This will create a file that takes up approximately 10MB of space for every minute recorded,so you will need plenty of free disk space. For voice or music to be embedded in a Web page, you can use a lower sample rate, a single channel and 8 bit resolution to create a much smaller file. Set the Recording Level     Now play part of the track and use the Volume Control program to set your recording levels. In Windows, the first screen of the Volume Control program is for playback levels. To get to the Recording Level screen, choose Properties from the Options menu and select the check box for Recording. Make sure the check-box for the LineIn volume control is also selected. Click OK and the Record Level screen will appear. Set the Monitor Record Level option in your recording program to On, and, as the track plays, adjust the slider for LineIn so the level meter shows a strong signal, but not so strong as any peaks cause the meter to go into the red area. Record the Audio     Lift the stylus and queue up the beginning of the track. Click the Record button in your recording program and then lower the needle. Make sure no other programs are running while you record. When the track is finished, click the Stop button and lift the stylus.	Remove Clicks, Pops or Hiss     Play back the track to hear how it sounds. Trim off any silence at the beginning and ends of the track If you have an audio clean-up plug-in, use it to automatically remove any clicks, pops and hiss. If you don't have an audio clean-up plug-in you can zoom in to each click or pop, select an adjacent cycle of the waveform at the zero crossing points, copy it to the clipboard, and then paste it over the cycle that contains the click. Listen to the track again and run the hiss removal if necessary. Normalize the Volume     Normalize the track to adjust the volume up or down so that all tracks will play at a similar level. A value of 97% usually works well if your software normalizes by peak level. More advanced programs, such as CoolEdit Pro, can normalize by average levels, which is much more accurate. At this point, you may want to add a fade-in or fade-out. Some CD recording programs, such as Nero can automatically crossfade tracks as the CD is recorded. Save to a WAV or MP3 File     If you intend to record the track to an audio CD, save it to a PCM format WAV file (PC) or an AIFF file (Mac). Save the file to MP3 format if you want to play it from your computer or on a portable player. Record an Audio CD     Now you can use a CD-Recordable drive to create a Red Book audio CD that can be played in most CD players. Avoid using CD-RW media because it will not be compatible with most CD players.     It pays to experiment with a short clip before you record and clean-up an entire album. Find out which settings work best for different types of recordings and write these down for future reference.     Many of these old 78s and LPs are irreplaceable, so it pays to preserve them in a digital format. If you ever have recorded a cassette or reel-to-reel tape, you should be comfortable with this process and delighted with the ability to improve the quality of the audio.     For more information on recording from vinyl LPs to audio CDs or MP3 files, pick up a copy of The MP3 and Internet Audio Handbook for $19.95 from www.TeamComBooks.com or read it online for free at (www.MP3Handbook.com).     Bruce Fries is a writer, technology consultant and entrepreneur who lives in Silver Spring, Maryland. He is an associate of the Audio Engineering Society and the founder ofTeamCom Books, a customer-focused publishing company that combines the best of traditional print publishing with new media, such as e-books and the Internet. He is the author of The MP3 and Internet audio Handbook.
Number 223 - December 2001