Converting LPs to CDs using your Computer
I've got a small collection of LPs, and I was thinking that it would be nice to be able to take these with me and play them in the car. Previously, this would have best been achieved by recording the records to cassette tapes, but these days the CD has become the standard media for mobile (as well as home) audio. Some might argue that portable music players, such as the iPod, Zen, and Zune have become the new standard for mobile music, but the process of getting music from vinyl to any sort of digital music file basically requires the same steps, up until the final output.
Hardware
Assuming you've got a collection of old records that you also would like to convert into digital music files, what will you need to make this happen? Obviously, you are going to need a record player. Most people with a collection of LPs are likely to have a turntable. However, I probably am not the first person to discover that their nearly 30 year old turntable no longer functions properly. Faced with the choice of repairing it or buying a replacement, I went with buying a replacement. My reasoning was that my old Technics SL-20A (seen below) wasn't a very expensive turntable and the motor seemed to be failing (replacing the belt still left the turntable with a problem of not rotating at a steady speed).
This is a cautionary tale, because I found out that today's less expensive turntables are not of the same quality as those that were available back when vinyl was the heart of everyone's stereo system.
I picked up an opened-box, but unused, Technics SL-BD20D on eBay.
This model seems to be among the last of the turntables that Technics's made for home entertainment. Currently, Technics only manufacturers turntables designed for DJs who are mixing club music. I was disappointed to discover how poorly this turntable compared to my old one. The cartridge and stylus simply did not have a very good sound, and the SL-BD20D's tonearm had no provision for adjusting the balance or anti-skating force. These features are used to properly set the tracking force when installing different cartridges. Below and on the right, you can see the adjustments available on the SL-20A's tonearm. At first glance, you might think that the SL-BD20D's tonearm, on the left, is also capable of these kinds of adjustments, but it isn't.
Fortunately, the Audio Technica Signet cartridge from my old turntable was close enough in size and weight to the one that came with the SL-BD20D that I went ahead and made the switch. While the result is less than ideal, it has worked well enough.
If I were to do this over, I probably would still look for a replacement turntable, but this time I would realize that a good turntable is going to be more expensive. The lower end turntables don't offer the same quality that they use to. Audiophiles constitute what is left of the market for turntables; therefore, these products are aimed towards them. (I'm leaving aside the DJ mixing turntables, since these are not very good choices for home audio.) Manufacturers who are still building high quality turntables, such as Pro-Ject, Music Hall, and Rega, offer "entry-level" models; however, these "budget" turntables are in the neighborhood of $300-$350. Nevertheless, compared to the Technics SL-BD20D, which currently sells for around $150 to $180, these turntables offer a lot better sound quality.
Another option would be to look at the older, "vintage" turntables on eBay. These were manufactured back in the 1970's and early 1980s, when turntables were the heart of every stereo system. However, pursuing this route will require a fair amount of research on your part, since you'll need to figure out which of the many turntables that are available offer good quality at a reasonable price. You also have to be concerned about whether any older turntable is still in good working order. Your best option is to find a reputable seller who knows the turntable well. For example, a seller who is also the original owner of the turntable should be able to fully describe what condition the turntable is in. You can also find some older turntables that have been professionally serviced and tested before being placed up for sale. Sometimes, these reconditioned turntables are even sold with some degree of warranty.
Once you have the issue of a turntable squared away, you still have to consider how to hook it up to your computer. Generally, you cannot hook up a turntable directly to your computer's soundcard. Record tracks are laid down in a fashion that emphasizes the high frequencies and de-emphasizes the low frequencies. This is done in order to make more efficient use of the physical dimensions of the record groove. As a result, the output from your turntable needs to be put through a specific kind of pre-amplification before it will sound right. Back when everyone was listening to vinyl records, the amplifiers and receivers that people plugged their turntables into had phono sections that provided the proper pre-amplification for the turntable's output. Using your stereo amplifier or receiver as an intermediary for hooking your turntable up to your computer is one solution. Connect the turntable to the phono-in jacks on your amplifier and hook your computer up to the amplifier's record-out jacks.
Many newer amplifiers and receivers no longer include a phono preamp section. As a consequence, you'll find that some turntables now have their own phono pre-amp built in. Unfortunately, many of these turntables with the integrated electronics don't appear to be of any better quality than the Technics SL-BD20D, which I already complained about. Denon's DP-300F turntable with an integrated phono pre-amp may be an exception. At least from the pictures, it appears to have some of the features that you'd expect to see in a better quality turntable.
You may also have noticed that there are turntables that can be hooked up directly to your computer with a USB cable. These turntables have both an integrated pre-amp and an analog to digital converter. Many of these turntables are offered as part of a LP to CD kit, and they are of lesser quality than I feel comfortable recommending. However, Pro-Ject's Debut III USB turntable appears to be a valid option. Pro-Ject has taken their entry-level (audiophile) turntable and built in a phono pre-amp and an analog to digital converter. Although the turntable itself is better than what you will find with the other USB turntables, I have no information on the pre-amp or the analog-to-digital converter being used. I would like to think that it is of the same quality as the turntable.
A more flexible option is to purchase a separate phono pre-amp, which can be used with any turntable. I found a used Creek OHB-8SE on eBay. This allows me to hook my turntable up to my computer without moving my integrated amplifier to where my computer is, and this particular phono pre-amp provides better sound quality than the built-in phono section of my inexpensive amplifier.
Note the ground screw on the back of the pre-amp. You'll need to connect the ground wire from your turntable to the ground screw on your pre-amp or amplifier in order to prevent an unpleasant background hum from being generated.
The next step is to connect your amplifier, receiver, or preamp up to your computer. You likely will need a different kind of patch cord than the audio cables you typically use, which have RCA connectors on both ends. You'll need a patch cord with a mini-jack on one end (to plug into your sound card) and RCA connectors on the other end to hook up to your audio system. I picked up the one shown below at my local Radio Shack.
You may need to consult the manual that came with your computer or soundcard in order to correctly identify the "line-in" jack, since these may not be clearly marked. (The lay-out of the jacks on my Audigy 2 ZS soundcard is shown below.)
The Creative Audigy 2 ZS sound card that I've been using is primarily aimed at computer gamers, but it does an adequate job as an analog to digital converter. I think that most of today's computer sound solutions should be usable for this task. However, if you are looking for a sound card more specifically designed for the purpose of working with music on your computer, M-Audio offers a range of these products. Their Audiophile 2496 seems particularly well suited to plugging in stereo components, as it comes with two pairs of RCA connectors on it.
Beyond these higher end sound cards, there are external analog-digital converters. Because these components do the digitalizing of your sound outside of your computer's electronically noisy environment, there is an argument to be made that they provide a better solution than using your computer's sound card. The drawback is that these converters tend to be rather expensive. For those with a do-it-yourself bent and some skill with a soldering iron, Hagerman Technology offers the Ripper, a phono pre-amp and analog/digital converter in one. You can either purchase this as a kit or pre-assembled.
A final piece of hardware that you might find useful, is a set of headphones. This is optional, of course, but I find using headphones helpful when listening carefully to the music, in order to hear how much noise is present. Computers tend to be a bit noisy, due to their many fans, and headphones can help block out this external noise. Headphones that completely enclose the ears (circumaural) seem best for this purpose. I've been using Sennheiser HD 280 Pro headphones, which I picked up refurbished from NewEgg.
Software
Once you have your turntable hooked up to your computer, you'll need some software for recording and working with your digital music. I found three pieces of software that were very helpful. The first piece of software is free; it is an open source, audio editor called Audacity. You can use this software for recording your music to a music file, editing this file, breaking it into individual tracks, and exporting your music into various formats.
I've also relied heavily on the shareware program Click Repair, which does a very nice job of cleaning up much of the noise that you will run into on vinyl records. Old, beat-up records can be much improved, and records that are in pretty good shape turn out even better.
These two programs would probably be enough to get the job done, but I've also made use of another shareware program, Wave Repair. This program combines features for removing clicks and other types of noise with the ability to record and edit music tracks. In some ways, it combines the functions of Audacity and Click Repair into one program. However, I wouldn't recommend using just this program, since the two programs that I already mentioned have some clear strengths over Wave Repair in certain areas. For example, Wave Repair can only work with 16-bit files with sample rates of either 44100 or 48000 Hz, while Audacity allows you to record your music at much higher bit rates (32-bit) and sampling frequencies (96000 Hz). For repairing clicks and other small background noises, Click Repair can be run in automatic mode and will do a very good job on its own, while Wave Repair lends itself better to a manual process of going through a recording and fixing individual areas damaged by noise. Wave Repair's features are very well done, and I suggest that you at least take a look at this program.
Both Wave Repair and Click Repair offer free, trial periods during which these programs are fully functional. This will give you a chance to evaluate how useful these programs are for your needs. I think that you'll find Click Repair to be indispensable, and you may find Wave Repair to be helpful enough to pick it up as well. (Click Repair offers a 21 day trial period and a license sells for $35. Wave Repair offers a 30 day trial period and a license sells for $30.)
Procedure
Now that you have everything that you need, how do you proceed? A preliminary step might be to clean the record, before you play it. There is some disagreement about how necessary this is, but I think it comes down to the condition of the record. If a record has been well taken care of, you may not want to put it through the abuse of cleaning it. Rega makes this point very clear in their product manuals (as quoted below).
Don't use any record cleaner that works while the record is playing or any cleaners that use water or solvents. If you keep your records stored in their sleeves, avoid touching the playing surfaces, play with the lid down and keep all water and fluids away, cleaning should not be necessary. Don't worry about visible dust on the record surface, this is brushed aside by the stylus and any that collects on the stylus can be easily blown away. In general, record cleaning is overdone and one should not believe all the claims made by record cleaner manufacturers.
The disadvantage of frequently applying liquid cleaners is that you run the risk of creating a kind of sludge or residue that will dry and build up on your record. There are record cleaning machines, which use a vacuum to remove the cleaning fluids, but these machines are very expensive. If your records don't appear to be very clean, you may want to try cleaning them to see whether this will improve how they sound. There are many kits available for this purpose, just be judicious in their use.
Another preliminary decision that you'll have to make is about the settings to use when you record your digital audio file. Audio CDs contain 16-bit, 44100 Hz, WAV files; so, this should be the minimum setting that you record at. If you use Wave Repair for recording your music, you will be limited to 16-bit files with sample rates of either 44100 Hz or 48000Hz. Audacity will let you select higher sampling and bit rates. Its default bit rate is 32-bit, and it offers sampling rates up to 96000 Hz (at least with my sound card).
Does it matter whether you use something higher than 16-bits at 44100 or 48000Hz? Although there will those who disagree, the author of the Wave Repair defends his decision not to upgrade his software to support higher bit rates by saying that 16-bits is enough to capture all of the useful sound coming off of a vinyl record. In my limited experience, I haven't been able to tell any difference between working with 16-bit, 44100 Hz files and those recorded at higher rates; so, I'll have to leave it to you to reach your own conclusions on this.
When you begin recording your music, you'll need to experiment a bit with the input level. Keep an eye on the sound meters and make sure that the level does not go over 0 dB. If the sound level exceeds 0 dB, you'll end up with clipping, an unwanted distortion of the music. Wave Repair has some nice big meters to watch, which will make it easy to tell when your sound level is too high and clipping has occurred.
Audacity has adequate recording meters, which can be undocked from the main window and expanded.
You'll want to leave a cushion of a few dB when you're recording, for those occasions when the sound level peaks. After making a few recording trials, while watching the sound meter levels, you'll find the line-in, input level that works best with your set-up.
Once I've captured an audio file for each side of the record, I run each one through Click Repair. (Click Repair accepts 16-bit or 24-bit files with sampling rates of either 44100 or 48000 Hz. Either WAV or AIFF file formats can be used.) A De-click setting of 30 is a good place to start. I've been able to use a setting of 25 for records in good shape and gotten a good result.
Today's fast CPUs make fairly short work of processing these files (a Core 2 Duo E6600 @ 2.4GHz takes about a minute and half to de-click 20 minutes of music). This makes it easy to try different settings until you find one that sounds good to you. Keep in mind, a setting that works well on one record may not be the best one for another record. It will depend on how much noise has to be dealt with. My general tendency is to use the lowest setting that gets rid of most of the noise. I'd rather leave a bit of noise behind than de-click to the point that I risk cutting into the quality of the music.
Usually, a simple de-clicking process with Click Repair is sufficient to produce a file that I am satisfied with. However, I suggest that you explore some of the other things that you can do to retouch your digital recording, as these may be helpful when pulling music off of certain records. Take a look at Click Repair's de-crackle feature, Wave Repair's ability to work on individual trouble spots, and Wave Repair's filters for noise, hum, and rumble; these functions may be helpful if a simple de-clicking process doesn't get your recording into a condition that you are happy listening to it.
After I have de-clicked them (and done whatever other noise reduction is necessary), I use Audacity to trim off the excess sound recorded at the beginnings and ends of these two files. Audacity has a helpful feature that aids you in finding the "zero crossing" points when you mark a selection. Cutting your tracks at these points helps prevent a "pop" from being introduced when your track starts out. I next amplify each file to the point where the loudest portions are at 0 dB. (Actually, I use the same level of amplification for each file -- the lowest level, if one side could have been amplified a bit more than the other. I want the result to be consistent throughout the whole CD; so, I treat these two files as if they were one, by amplifying each one to the same extent.)
I've found that even after amplifying the music as much as I can, without introducing clipping, the CDs of my transferred music end up not sounding as loud as commercial music CDs. Some of this may simply reflect my combination of hardware, but I also think that music, as distributed on CDs, often is "compressed". Compression involves de-amplifying the loudest portions of the music so that you can re-amplify the whole track without pushing the loudest portions into clipping. While this makes the music sound more full, you lose some range in the louder portions of the music.
I don't have both a commercial CD and a LP of the same album to make a direct comparison; so, I experimented with what would be required to boost a recording from an LP up to a volume level that seemed comparable to a commercial CD. Below is my recording of a track from Rickie Lee Jones's LP ("On Saturday Afternoons"). This song primarily features quiet vocals.
Next, let's look at the CD track from a different album, which also features quiet female vocals, Robinella's "Solitude".
It is apparent that the music on the commercial CD will sound louder. If I amplify the Rickie Lee Jones song to bring the overall level of loudness up to something comparable to listening to the commercial CD, the track ends up looking like this (below).
Amplifying a relatively quiet song doesn't really affect the nature of the music, since no part of it is pushed to the point that clipping is a problem. However, you don't really want to amplify just some of the tracks on the album; for consistency, they should all be amplified to the same extent. The dilemma is that the loudest tracks on the album already are near to the point of clipping; so, amplifying them will result in clipping. The compromise solution is to first decrease the amplitude of the loudest portions of these tracks; then, the whole track can be amplified without clipping.
For example, below are two versions of Rickie Lee Jones's "Danny's All-Star Joint". The first is as it was originally recorded, and the second shows the result of compressing the track to the extent that it is amplified to the same degree as was the the "Saturday Afternoons" tune, which we looked at, above.
I think that you can see in the compressed file how the loudest portions have been de-emphasized so that the whole track can be boosted up to a higher level. This achieves the result of making my recorded CDs sound comparable in loudness to commerical CDs, but there is a loss of variation in the louder portions of the music.
The only reason that I could see to use Audacity or Wave Repair to compress music files and make them louder is so you could put your home-made CDs into a multiple disc CD player along with commercial CDs and not have to worry about the music suddenly playing too loud when it changed from one of your CDs to a commercial one. Personally, I'd rather avoid altering the music like this; so, I just keep my home-made CDs separate from the commercial one and remember to change my volume settings when I go from playing one type of CD to the other.
After trimming the files and amplifying them a bit, I break the files into separate tracks. I do this one at time by highlighting the portion of the file that I've identified as a single music track or song and using the "zero crossing" feature to make sure each section starts and ends at points where the music level is close to silent. Then, I split that highlighted portion off onto its own track. I do this for each song. Then, I go back through and export each of these tracks, individually, as a 16-bit, 44100 Hz, wav files. I name them something like "01NameOfthisSong.wav" to help me put them in the right order when I burn a CD.
I've often seen the suggestion to fade-in the beginning of each track and to fade-out the endings. My preference is to just fade-in the beginning of the first track and fade-out the end of the last track. I don't cut any of the sound out between the tracks; so, the pauses between songs will be the same as they were on the record. For this to work out properly, I need to make sure that my CD burning software doesn't insert any additional spaces between the song tracks on the CD. Nero, for example, will insert a two second pause between audio tracks by default, so, I need to check the option telling it not to do so.
I prefer not having any complete silences inserted into the CD, because I would rather have whatever background noise is present from my recording (even after cleaning it up) remain constant throughout the CD. I notice background noise much less and can more easily ignore it when there is no absolute silence for it to standout against. This is essentially the experience we have when listening to a vinyl record on the turntable. Unless the record is in poor condition and very noisy, we usually pay little attention to whatever little pops and clicks may be present with the LP. Of courese, this is a personal preference, and you should experiment to find out which options are most agreeable to you.
The suggestion that you try different things to see what sounds best to you is almost a theme running through this article. I think that it captures something important about taking on this project. I don't believe that transferring your LPs to CDs is something that you should feel in any hurry to accomplish. Recording and editing music files tends to be a pleasantly time consuming process; therefore, take your time and enjoy listening to your music as you go. If you like listening to music and if you like working with your computer, you likely will find converting your LPs to CDs to be a very satisfying endeavor. On the other hand, if your primary interest is the end result, you probably are better off just buying commercial CD releases of the music in your LP collection. There's no need to go to the trouble of recording your CDs yourself, unless you find the process enjoyable.
Further Reading and Other Resources
The author of Wave Repair, Clive Backham, provides a very nice summary of his experience with recording LPs and turning them into CDs. I highly recommend taking a look at this.
Here are few other descriptions of the process of transferring music from vinyl to CDs: 1) A Hardware Secrets Tutorial, 2) Part of a tutorial for using the Wave Corrector program, and 3) Another tutorial on transferring from LP to CD.
Looking for a turntable, pre-amp, or record cleaning supplies? I have not actually purchased anything from them, yet, but I sure have spent a lot of time browsing the Needle Doctor's website for information.
LP Gear and Music Direct are a couple of other sites you might enjoy browsing.
I've already mentioned NewEgg, as they are the first place that I go to when looking for what's available in the way of computer hardware; this includes sound cards.
November 16, 2007