Sample workflow for LP digitization

Ed 1Jan13: What is the policy on images in tutorials? My expectation is that most tutorial readers will be novice users of Audacity. As such they may well benefit from the additional handholding that images provide. As an example in the section where we deal with setting the recording levels I would suggest pictures which show meters at good recording levels (and maybe even one with overdriven levels) and probably a picture of the vertical ruler between the Track Info Panel and the Wavetrack.

Additionally, in the same vein, in the section where we deal with setting Audacity's project rate and sample setting, we parenthetically mention that these are the defaults with a link to the manual page describing where to control these settings. I would lean toward being a bit more proactive here; something more like "Open the Preferences dialog to the [Recordings page] and ensure that your settings are…"

Ed 1Jan13: this "intro" seems way too long IMHO. I think only the first 1.5 paragraphs should be in the "intro" and all in one paragraph. The rest of the material should be reworked for continuity and readability and placed right below the TOC (this also removes the visual clash of having to headings with no text in between them):

This tutorial outlines a set of example steps using Audacity to digitize LPs to create files that are ready for CD creation, loading into a digital jukebox or portable music player. There is no fixed "right" way of working - there are many alternatives; like any recipe, it can be adapted to suit your personal needs.

(TOC here)
Making vinyl to digital transfers is a skill and the more you do the more expert you will become. Consider starting out with an LP or singles that you are very familiar with; your first goal will be to ensure that you have as perfect a digital copy of the material as possible. Clean-up steps are optional and need only be applied if your recording requires them.

Note that this workflow does not at any stage necessitate the saving of an Audacity project (though you may wish to do that if you need to interrupt your work). Your final goal will be to export WAV files for CD creation or other file formats which might be more suitable for your needs.

While all of the processing in this tutorial is carried out using Audacity, some users may prefer to use alternative software for specific sub-tasks like noise removal and the removal of clicks and pops (Audacity's Click Removal may not give as good a result as other software).

This tutorial outlines a set of example steps that can be used to digitize LPs with Audacity, ready for CD creation or loading into a digital jukebox or portable music player.

It is not the only way of working - there are many alternatives. Like any recipe it can be adapted to suit your personal needs. Most of the clean-up steps are optional and need only be applied if your particular recording requires them.

You can work in AIFF rather than WAV if required.

Note that this workflow does not at any stage necessitate the saving of an Audacity project (though you may wish to do that if you need to interrupt your work). It relies on the export of WAV files.

All of the processing in this tutorial is carried out with Audacity. Some users may prefer to use alternative software for specific sub-tasks like noise removal and the removal of clicks and pops (current Audacity Click Removal may not give as good results as other software).

Making vinyl to digital transfers is a skill and the more you do the more expert you will become. Consider starting out with some LPs or singles that you care less about and only ever played infrequently. This way you will not need to go back and repeat important earlier transcriptions that you made.

Workflow

Audacity settings

Work with Audacity set to a project rate of 44100 Hz and 32-bit sample format (these are the default quality settings). You may use 16-bit if you prefer; it will give smaller working file sizes but you may lose a little quality in some of the processes. Export WAV files at 44100 Hz 16-bit PCM stereo, the standard required for burning CDs; this will also produce WAVs which are accepted for import by iTunes (and most other music player software).

Clean the LP

Cleaning the LP carefully and thoroughly before recording it will reduce the number of clicks and pops and will improve the quality of your recording.

Prepare a solution of lukewarm water mixed with a little dish washing detergent. Use a soft, clean washcloth (or piece of velvet) to carefully wipe the LP's surfaces - try not to get the label wet. The detergent will float away all the greasy fingerprints - a gentle scrubbing motion will help. Rinse in lukewarm water until all the detergent is gone. Finally, rinse in distilled water (which dries and leaves no residue behind). Air dry your record thoroughly before playing - do not be tempted to play the record "wet" as this may damage the LP and possibly your stylus.

There are a number of commercially available cleaning fluids and cleaning machines that you may wish to consider:

• KAB EV-1 Record Cleaner & KAB cleaning solution
• Disco Antistat
• Discwasher

Flattening a warped LP

If an LP is warped it may not track or play properly; if so, you could try to ease the warps in the vinyl. Place the album in its sleeve and cover between two sheets of flat wood (plywood, glass or similar) in a warm room and place some heavy (but not too heavy) weight on top. Leave in the warm room for several days and then try playing it.

Alternatively, stabilizing rims on a conventional turntable or expensively, laser turntables can be used to safely play all but the most extremely warped LPs.

Recording levels

Read this page about making a test recording then make a test recording of portions of the LP (or even a whole side) so as to check the levels. It is important to avoid any clipping during the recording! Try to aim for a maximum peak of around –6 dB (or 0.5 if you have your meters set to linear rather than dB).

Enlarging the Meter Toolbar by clicking and dragging helps with this task; you should read this section about resizing the Meter Toolbar.

Capture

Ed 1Jan13: "Record both sides…" make some sense but is not really necessary; requires additional handholding here –we need to explain both Append Record and Pause then continue recording.

Record both sides into the project prior to doing the processing; you may, if you wish, work with a single side of an LP as that gives a smaller working set. After recording you may find it helpful to zoom out to display the entire recording in the Audacity window.

Raw master backup

Ed 1Jan13: "Export a single WAV for this side of the LP at 32-bit float" I suspect that this is not easy for the novice to figure out since the only solution is "other uncompressed files" which says nothing about 32-bit float – Needs more handholding.

Also note that this assumes that the dear reader has ignored our previous suggestion to record both sides of the LP into a single project– I am going to change this wording…. Also note that the original wording seemed to imply that this "raw capture" would also maintain some form of editorial trail – I changed that wording as well.

Export a single WAV for this recording at 32-bit float (not 16-bit). Retain this WAV file as a maximum quality "raw capture" file that you can import back in to Audacity later to start over (if you damage the project while working on it).

Remove DC offset

DC offset can occur at the recording stage so that the recorded waveform is not centered on the horizontal line at 0.0 amplitude. If this is the case with your recordings, see the Normalize page for how to use Normalize to remove DC offset and how to check if your Windows sound device can perform this correction automatically.

Place-holders for song labels

Ed 1Jan13: Why do this now? If we are going to use these labels further down in the tutorial then it would seem important to get them more closely placed than "the approximate point between". Maybe just a few words about zooming in to get the label and the dead space?

Mark the approximate label points - click in the waveform at the approximate point between the tracks on the album, press CTRL+B then ENTER; don't forget to insert a label at the very beginning for the first track. Alternatively you can mark a label point while recording (or on playback) by pressing CTRL+M.

Peter 25Nov12: ToDo If and when an improved Sound-Finder/Silence-Finder gets implemented consider adding advice about sound/silence finder as a way to place labels.

Remove subsonic rumble and low frequency noise

Use Effect Menu > High Pass Filter... with a setting of 24 dB per octave rolloff, and a cut-off frequency of 20 - 30 Hz to remove unwanted subsonic frequencies which can cause clicks when editing. If your record is warped, this will definitely generate unwanted subsonics, in which case consider a lower cut-off frequency.

This step can probably be omitted given a flat record and high quality turntable, arm and cartridge.

Remove clicks and pops

There are a number of ways you can use Audacity to remove clicks and pops from your recording. First, without zooming in too far, visually inspect your recording for clicks - they will show up as abnormally tall (sticking up or down), very narrow (one or two pixels wide) vertical lines protruding from the waveform. Select a region with one or more of these spikes and listen to it to ensure that they are clicks. After determining that your selection indeed needs to have clicks removed use the Click Removal effect with various settings - preview the effect with these different settings to get the best results. Then, using the settings from your preview testing, use the Click Removal effect on selected regions of audio or on the whole project.

Clicks which did not get removed with Click Removal can be treated individually with other methods. These methods are only really useful if you have a relatively small number of clicks and pops to deal with; otherwise, these approaches will be too labor-intensive and time-consuming:

• Try Audacity's Repair effect. This repairs a very short length of up to 128 samples by interpolating from the neighboring samples. You will need to zoom in to see the individual samples to use this effect.
• For somewhat longer regions of audio, try:
  • Draw Tool. You need to be zoomed in to the individual samples to use this. Some patience may be needed with this tool, but the principle is to put samples back into line with their neighbors so that a smooth contour is presented.
  • Hard Limiter... This is an extreme compressor effect, but can be effective used on an individual click. There is no need to zoom right in to sample level to use this.

Ed 1Jan13: If we are going to suggest using the Hard Limiter as an appropriate tool for this we should probably go into some detail about appropriate settings ranges – way beyond my remit!

Remove hiss and high frequency noise

Get a noise sample from either the lead-in grooves immediately before the music starts, or from a lead-in between tracks. The length is not important but, typically, it will be less than a second; what is important is that you have a true representative sample of the noise without any audio signal at all (such as a very quiet fade lead in). Try amplifying the sample and audition it to ensure that no real audio signal is present. If it's OK, undo the amplify, Get Noise Profile with the Noise Removal effect then re-apply the Noise Removal effect with these settings:

• Noise reduction - no more than 12 dB (9 dB is a good guideline)

Ed 1Jan13: ???

• Sensitivity - 0 dB

• Frequency - smoothing 300 Hz
• Attack/decay time - 0.25 seconds

Ed 1Jan13: Why are the above values not the default?

Noise reduction is always a compromise because, on the one hand, you can have all the music and a lot of noise and, on the other hand, no noise and only some of the music. Try different settings on the "Noise Reduction (dB)" slider until you get the best compromise.

Whether you need to use Noise Removal will depend on the quality of your LPs, your stylus and cartridge.

Silence the inter-track gaps

Ed 1Jan13: Here is where I think it most appropriate to suggest that the labels be created. The user is already zoomed in and working in the appropriate spot.

These are rarely truly silent so you may want to replace them with silence by selecting the gap and using CTRL+L or the Silence Generator effect. Edit the inter-track gap as desired to around a maximum of 2 seconds; you may wish to use a shorter gap or even no gap at all for some recordings.

By default CD burning software almost always adds a 2-second gap between tracks. Check for any options to turn this off, for "gapless burning" or "Disc-at-once (DAO)" that you can enable.

Fade Ins/Outs

You may wish to more cleanly Effect > Fade Out the track ends and Effect > Fade In the track beginnings. Normally fade outs should be longer (typically a few seconds), and fade ins, if required, quite short (typically a fraction of a second).

Consider using Effect > Studio Fade Out instead of the linear Fade Out. It applies a more musical fade out to the selected audio, giving a more pleasing (more "professional studio") sounding result.

You may also get a more musical fade-in by applying Effect > Fade In multiple times to the selected audio; three times is a good guideline. This will produce a shaped, curved, fade rather than a linear one.

Peter 1Jan12: ToDo-2 If we do produce a Studio Fade In then the above advice can be replaced

As an alternative: you may find it easier to do: fade-out, silence gap, fade-in, shorten gap, adjust label position – in that order, one track at a time.

Although no keyboard shortcuts for effects are provided by default in Audacity it is possible to set up your own shortcuts for any effects you choose. You may find it particularly beneficial to assign shortcuts for fade-in and fade-out as these are used repeatedly. For instructions on how to do this please see the Keyboard Preferences page in the manual.

Adjust label positions

Ed 1Jan13: Remove this section completely as well as the much earlier section and put all of this information in the section on silencing inter-track gaps.

If you are using a 2-second gap, adjust the label position as desired to be 0.5 seconds before the start of the next track. To move the label, drag by its center circle.

Track names

Edit the labels for the song names - we suggest using "01 First Song Name", "02 Second Song Name", and so on as this helps keep them in the right order for CD production or loading into iTunes. You may find that changing the zoom level will help you with this task; you can advance to the next label by ensuring that the focus is in the current label then using TAB.

A new feature was added in Audacity 1.3.12 which will allow you to automatically prefix named tracks with a sequential two-digit number. In the "Name files" section of the Export Multiple dialog select the Numbering before Label/Track Name radio button.

Ed 1Jan13: Given that this manual is now reflecting version 2.X do we need the preface in the previous paragraph in re. the "new feature… 1.3.12"?

Amplitude adjustment

Normalize the amplitude of the recording; either do each track of the recording individually (especially if the tracks will be randomly played from a library containing many different styles of music) or, do the whole recording at once (which will work fine if all the tracks have the same average volume). Use Effect > Normalize as the last editing step to bring the amplitude to around -3.0 dB. The Normalize effect can be set to either:

• Adjust the amplitude of both stereo channels by the same amount (thus preserving the original stereo balance)
  

or

• Adjust each stereo channel independently (this can be useful if your equipment is not balanced)

Ed 1Jan13: I feel that the On/Off nature of the above control would be better presented as something other than an unordered list; just make it a sentence:

"The Normalize effect can be set to either adjust the amplitude of both stereo channels by the same amount (thus preserving the original stereo balance) or adjust each stereo channel independently (this can be useful if your equipment is not balanced)."

Compression

The Compressor effect reduces the dynamic range of audio. One of the main purposes of reducing dynamic range is to permit the audio to be amplified further (without clipping) than would be otherwise possible.

Compressor makes the loud parts quieter and (optionally) the quiet parts louder. It can be very useful for listening to classical music in a car. Such music normally has a wide dynamic range and can thus be difficult to listen to in a car without constant volume re-adjustment.

Export a set of WAVs

Use File > Export Multiple to produce a set of WAVs for each track on the LP at 44100 Hz 16-bit PCM stereo. Audacity will down-sample on export from 32-bit to 16-bit. Shaped dither noise will be applied by default to cover any defects (clicky noise) that may result from the conversion from 32-bit to 16-bit. Advanced users can change the type of dither, or turn it off, in Quality Preferences.

In order to facilitate later retrieval and use place all the files for a particular album in a specifically named folder for that album.

Export Labels

Some users advise a final step of exporting a file containing the labels. Use File > Export Labels... This produces a text file that you can later re-import using File > Import > Labels..., should you wish to re-edit from the raw capture file that you backed up earlier in the workflow.

Backup

Backup your WAV files - you don't want to lose all that valuable work and have to do it all over again, do you? Use a dedicated drive(1+ TB external drives are convenient and economical) to hold the WAVs; you may create a sophisticated file structure - each LP can be stored in its own folder (named for the album) within a folder named for the artist (or, perhaps, composer for classical) to make retrieval easier.

Alternative software

• GoldWave: Though nominally not free it is effectively a top class, free click remover as well as an excellent alternative audio editor (its click removal is an effect, just like in Audacity). The trial version limits you to a hundred or so commands per session, and a total number of several thousand commands before it expires, but if you export from Audacity as 32 bit WAV and just do Click Removal in it, you should be able to do several hundred records for free. Note that Audacity's Noise Removal is probably superior to Goldwave noise removal on the whole.
• Gnome Wave Cleaner: Only for Linux users.

Ed 1Jan13: I suggest adding a little bit more information on gnome wave cleaner - beyond my remit.

===Low Frequency removal=== ??

Clicks and pops

• ClickRepair: A good tool for removing clicks and pops is Brian Davies' ClickRepair. Some new users may find it a bit intimidating as an entry level tool but, once you have understood the settings you want to use, it is effectively an automated tool. It is not free, but many users report that it saves a lot of time and produces good results.

You may find the default settings for this application remove a little too much signal. An alternative recommendation:

• DeClick = 30 (default is 50)
• Pitch Protection = "on" (default is "off") though leave this "off" for brass recordings
• Reverse = "on" (there is no processing penalty for this and it helps on percussive music)
• Method = Wavelet

Hiss and noise removal

• DeNoise: Brian Davies also supplies a tool called DeNoise; this is effective at removing noise and hiss. As with ClickRepair, some new users may find it similarly intimidating as an entry level tool. Users report that settings normally have to be reset for each recording to optimize the noise removal thus making it difficult to use in a semi-automated way.

Steve 14June12: Bias (makers of SoundSoap) have closed. SoundSoap is no longer available.

• Peter 14Jun12: Thanks for that update Steve.

Ed 1Jan13: The direct links to the download pages for GoldWave and ClickRepair were both broken; I redirected them to the main pages for now. How do we wish to deal with this sort of problem? The highly qualified direct link to the download pages seem much more likely to change then the links to the main pages. My impression is that, generally, most pages which refer a user to an external link do so to the main page not the download page.

Compression

• There are some alternative compressors available, see Compressors in the Wiki for ones that we know work well and are free to use.

Links

|< Tutorial - Copying tapes, LPs or MiniDiscs to CD

>  See also tutorial on: Recording 78rpm records