A cappella Liner Notes Best Practices

© 9-12-2013 Jonathan Minkoff (some portions © 2012, 2013 and 2015)

This article discusses the best practices for providing credits on a cappella recordings. 

If you only take away only one lesson, make it this: credit all composers and do not confuse composers with "original" artists. As of the writing of this article, this is the most common and egregious error in a cappella liner notes.

Additionally, this article will include many customs unique to the a cappella community while also debunking legally dubious or nonsensical omissions that have grown more commonplace, particularly in collegiate and high school a cappella.  

The complete article is extensive, so to assist those seeking quick answers, we begin with two lists: 

1. minimal credits; and 
2. best credits. 
   

The two lists obviously overlap since "best" includes "least." These reference lists do leave many issues unaddressed, and so they are followed by a section focused on underlying principles, debated issues and in-depth discussion. Read on for everything you ever wanted to know about credits!

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Minimal Credits
Here’s the absolute minimum credit you should ever provide:

• Song title (in title case, not in quotes).
• Your group's complete name, including school (if applicable) somewhere on the album.
  
• Complete names of all composers, separated by commas, listed in alphabetical order and preceded by the word "by". This credit belongs in the individual song credits. Do not confuse composers and original artists.  
  
• Soloists' complete names separated by commas, listed in order of appearance. This credit belongs in the individual song credits.
• Complete names of all arrangers, separated by commas, listed in alphabetical order and preceded by "arranged by" . This credit belongs in the individual song credits.
• The names and studios of all those responsible for tracking, engineering, editing, mixing, producing and mastering. This credit belongs in the individual song credits unless many tracks share the same credits, in which case the information can be credited elsewhere in the liner notes.
• ℗ + name of copyright holder in the sound recording, and date of album completion. This credit is legally important and belongs once, somewhere in the credits. However, in the rare instance when individual tracks have separate owners, then the credit belongs in the individual song credits.
  
• Complete names of any photographers or art designers. This belongs in the general credits or next to or on the appropriate photos. If placed on the photos, care must be given to text size. It should be small enough not to distract, but big enough to read. Large credits look like the copyright was placed to prevent copying and the group used the image without permission. Whether true or not, this creates an amateurish look that should be avoided.
• The complete names of all performers, ideally separated by part and role, such as music director. 

If you do this much, you can sleep easy at night. Of course your listeners will crave more. So aim for the best!

Best Credits
Here are the best credits you can provide. This list consists of every credit noted above with the addition of several additional categories.  Detailed discussion follows this second list. 

Just make sure that, if one of these categories applies to your song, then anyone looking at your liner notes will easily be able to determine the complete names of the following contributors (examples in brackets):

• Song title (in title case, not in quotes) [Wanna Be Startin' Somethin' ] or, in the case of medleys, separated by backslashes and presented in order of appearance: [Beat It/Thriller/PYT]. Do not say Michael Jackson Medley. That is not the title of any of the songs. Do not say Beat It/Thriller Mash-up. Mash-up is also not the title of the song.
• Your group's complete name, including school (if applicable) [The Boston University School of Law LegalTones]
  
• Complete names of all composers, separated by commas and preceded by the word "by". This credit belongs in the individual song credits. Do not confuse composers and original artists.   [John Lennon, Paul McCartney]. Do NOT write [OBP The Beatles]
  
• Copyright symbol and date the song was composed. [©1963]
  
• The composers’ publishers [123 Music, etc.]
  
• The composers’ society [ASCAP, BMI, SESAC, etc.]
  
• Complete names of all arrangers, separated by commas and preceded by "arranged by" or "arr." . This credit belongs in the individual song credits. [Arr.: Boba Fett, Jabba T. Hutt]
  
• The arrangers’ publishers [Killer Arrangements Music, LLC]
• Soloists' complete names separated by commas in order of appearance. This credit belongs in the individual song credits. [Solos: Jar Jar Binks, Deke Sharon]
• Vocal percussionists, in order of appearance or alphabetical order [VP: Wes Carroll, Marty Gasper]
• Special sounds like whistle, rap, DJ scratching, weird scream,  etc. [yodel: Ian McDermitt]
  
• The names and studios of all tracking engineers, editors, mixers, producers and masterers. This credit belongs in the individual song credits unless many tracks share the same credits in which case the information can be credited elsewhere in the liner notes. [Tracked by Joe Shmoe for Joe Shmoe Studios. Edited by Happy McDonald for Happytime Studios. Engineered by Jane Smith for Makin It Up Studios. Mixed by Marty McFly for Time Travel Studios. Produced by Jonathan Minkoff for Evil Giant Studios.]
• In the extremely rare case where your recording uses sound samples or segments of another recording (something you need permission to do), your liner notes should state "contains elements of" or "contains samples of" [contains samples of Thriller]
• All composers of the sampled recording
  
• The publishers of the sampled recording
  
• Record company of the sampled recording
  
• Performing group of the sampled recording
• "Used courtesy of " then list the owner of sound recording who granted permission
  
• ℗ + date and name of owner of the copyright in the sound recording. Or "Copyright in the Sound Recording" plus the date and name. [℗ 2009 Jaybird Records Inc.]
  
• Complete names of any photographers or art designers. This belongs in the general credits or next to the appropriate photos.
  
• The complete names of all performers, ideally separated by part and role, such as music director, alto II, etc. and, if you are a scholastic ensemble, consider including the graduation year. 
  
• Do NOT write out or translate lyrics unless you have permission from the composer, or the song is in the public domain. Paying compulsory licenses to the composers does not grant you permission to reprint the lyrics. However, with non-English lyrics, you are encouraged to include a short summary of the song's story.
• Do NOT credit any performing artists who have performed the composers' work prior to you unless they are actually performing on your album.

OK, short attention span people, you can stop now. I'm sure your head hurts. Everyone else, let's start the analysis. 

The Function of Liner Notes
Information provided on liner notes serves multiple functions:

• Historical Accuracy. Clear, accurate and complete liner notes are the primary historical source for information about the album. Any claim about having worked on the album will first be checked against the liner notes for accuracy. That's not the end of the analysis, but it is the universal starting place. And keep in mind that recordings live a long, long time. Even if you think the information isn't important now, you never know when an old recording will become very important (The group, Straight No Chaser was famously signed to a major record deal after a ten year old recording went viral on youtube.) 
• Money. While most recordings fade into the digital ether, you never know when a song will generate real income from plays, sales or licensing. The performers on your recording have a right to be paid for digitally streamed performances of the recording; the composers have a right to be paid for physical and digital copies, as well as all performances. Liner notes help establish those entitlements. 
• Fans. Twitter followers, facebook "likes" and youtube "thumbs-ups" matter to many artists. They are often the precursor to income, and many artists invest in their careers by agreeing to unpaid or poorly paid work just to get those fans. Liner notes are essential to this process. It's nearly impossible  to support a singer, group or vocal percussionist who remains uncredited. 
• Future Business. Producers, mixers, arrangers and even soloists all get their next job when people hear their current work and then seek them out. Liner notes should make that process frictionless.
• Awards. Whether we're talking the Grammys or just the CARAs, you can't win for "best anything" if your name isn't in the liner notes.
• Legal Compliance. The US Copyright Act grants artists the right to cover songs written by others, without their permission, if the compulsory licenses are properly paid. Failure to credit the composers is a red flag that the compulsory payments may not have been handled properly.
• Compliance with International Standards. See this guide for metadata standards.

Where Do Credits Go?
As mentioned above, credits are usually divided into two areas on CD liner notes: 

1. Per track, underneath the song titles; and also 
2. In the general credits applicable to the entire album. 
   

By contrast, digital metadata (or ID3 Tags) are usually entered into predetermined fields which then stay with the audio information contained in the digital file. This information is automatically displayed by many devices when the music file is played. 

Each music application is different but, on iTunes this information is entered here: 

          single click the track to highlight then 
          ->file 
                 -> get info: info tab

Alternatively, on a mac, one can click to highlight the track, and then press command and i simultaneously to edit track information. Tips for editing ID3 tags in iTunes can be found here.


CD Liner Notes
Some best practices regarding liner notes benefit from further discussion.

Song Titles
Unless you are e.e. cummings, the poet famous for eschewing capitalization, you should probably write your song titles in title case [The Wizard of Oz]. This becomes more difficult when the original composers (or their graphic artists) get very creative with their use of capitalization. Keep the original formatting where it remains consistent, and use a licensed source like iTunes for "correct" spelling and capitalization.  There is no need to put song titles in quotes. Bold, underline or other embellishing designs are often used, but this is left to the discretion of the art designer. 

Below are the liner notes for Prince's masterpiece, "Purple Rain". 

Common practice has been to maintain Prince's choices in spelling [I Would Die 4 U] but to ignore his original capitalization choices [BABY I'M A STAR, take me with u] and replace them with title case [Baby, I'm a Star, Take Me With U].

In the case of a medley or mash up (which many groups record, but which readers should know falls in a legally grey area at best, and is completely illegal at worst), song titles should still be written in title case, and then, in order of appearance, separated by a slash [Yesterday/Take On Me/Beat It]. Again, do not include quotation marks. It is customary not to repeat a song title, even if it repeats its appearance in the mash-up arrangement.

Composers
Composers' names have been disappearing from the liner notes of collegiate albums. This is obviously disrespectful. It's also a red flag that proper royalties may not have been paid.

So for both moral and practical reasons, all composers' full names should be credited, either as they list themselves [Rodgers and Hart; R. Rodgers and L. Hart] or alphabetically, usually preceded by the word “by”. Sometimes this is noted as “words and music by” or  “lyrics and music by” or in certain appropriate cases, “music by A and B; lyrics by Y and Z”. 

In the case of mash-ups, make sure the reader can clearly tell which composers wrote which songs. 

It can't be overstated: do not skip the composers' names. They are the only people involved in your recording process who haven't given permission. Without them, you'd have nothing to sing. Remember not to confuse composers with original artists. The Beatles did not compose any songs; John Lennon and Paul McCartney did.

Publishing Companies and Composers' Societies
Thorough liner notes will list the publishing company [123 Music] along with the composers’ names, and the composers’ society [ASCAP, BMI, or SESAC]. This information is always uncovered when making the correct royalty payments to the composers.

Arrangers
List all arrangers' full names, either as they list themselves on the arrangement, or alphabetically. The names are often preceded by “arranged by” or “arr.” 

If you altered an arrangement made by another arranger, you should say "arranged by (you), based on an arrangement by (the prior arranger)". 

You should consider this credit in the light of academic plagiarism: using the work of another arranger without credit may be legal in certain situations, but it isn't honest and it tends to anger people when they discover it. Failure to provide proper credit places your own work and reputation in jeopardy. In other words: bad juju.

Notwithstanding the comments related to honesty, in the US, it is actually legal to alter arrangements of non-public domain songs, if the arranger whose work you are using did not get at least one composer's permission to make their arrangement. This is because arrangements made without the composer's permission are not protected by copyright. Obtaining composers' permissions can take a great deal of time and effort and as a result, the overwhelming majority of contemporary a cappella arrangers just arrange and hope for the best. Credit them without regard to their legal rights.

Finally, the case of the literal transcription requires discussion. If your group's arrangement is extremely similar to an existing recording, it may be appropriate to credit your arrangement as based upon that prior version. The difficulty comes in the fact that many artists do not credit anyone with arranging. Producers, performers, uncredited ghost arrangers and even session players may all contribute to the final recorded arrangement. Where your arrangement varies significantly, it isn't necessary to credit anyone. But where your arrangement is a near duplication, or a transcription, it might be appropriate to credit the version itself [Arranged by Jane Smith, based upon the arrangement featured on "The White Album" as performed by The Beatles. © 1968]. This is especially true when your arrangement is based very closely upon a different artist's re-imagined version of a song. 

How much similarity requires a credit? The answer lies in the source of the arranging ideas. If the source of your arranging ideas comes from the melody, lyrics or chord progression of the original song, then you don't need to credit anyone but yourself as arranger. If they come from the arranging ideas of another arranger or artist, credit them. 

Soloists
Credit soloists' full names in order of appearance, preceded by “solo”, “duet”, “trio” or whatever is appropriate. Where the parts enter simultaneously, credit the duet in alphabetical order and if possible include an indication that would allow listeners to know which voice is which. This may not be necessary when gender is an obvious distinguishing characteristic. But if two tenors are dueting, best practice is to note a distinguishing characteristic like voice part [tenor 1 solo: Bob Costas; tenor 2 solo: Michael Jordan]. 

Do not identify a soloist by reference to another performer. In other words, do not credit [Rhianna Solo: Jane Smith]. Such a credit implies that the recorded performer is deliberately attempting to imitate the previous performer. Your soloists are almost always interpreting the song, not doing an imitation of another artist. The former is singing; the latter is voice mimicry.  

Occasionally a singer who is not a member of the group will sing on a recording. It is appropriate to credit the full name of any such guest artist, preceded by “featuring” or “feat.” 

When a guest artist is featured in non-a cappella music, it has become commonplace to include parentheses and the featured artist's name in the song title itself. This came as a result of contract negotiations among artists seeking better exposure. Since song titles aren't altered by the participation of performers, this information is more logically reported elsewhere, however the practice has become common.

Vocal Percussion or Beatbox
List all vocal percussionists' full names in order of appearance or, if not applicable, then in alphabetical order. This can be abbreviated as “VP” or "vp". In contemporary a cappella, the terms "VP" or "vocal percussionist" are typically favored over "beatbox" or "beatboxer" in credits. 

Some argue that beatbox differs from vp in that it is used primarily in hip hop music and not pop, rock or jazz, and that this stylistic difference determines the appropriate term. Others argue that while vocal percussion consists almost entirely of drumming noises, beatboxing often incorporates simultaneous singing, humming, vocal special effects, horns, DJ scratching noises and even rap. Beatbox drum sounds are also typically more imitative of a drum machine rather than of acoustic drums. 

Regardless of the term you choose, readers will understand that either label refers to the creator and performer of drum noises on a given track. In heavily produced tracks, this raises an issue.

If a track has vocal percussion that has been so heavily altered in the studio that the final product is not recognizably (or authentically) an individual’s performance, but rather a “studio construction” that owes its identity to the programming of an engineer or producer, then it is more appropriate to separately credit "drum programming" and possibly "percussion sounds". Alternatively, all VPs whose sounds are used, but who cannot be said to have performed the final product on a given track, may be listed in the general section of the liner notes without reference to the specific tracks on which they appear.

The key is to to avoid crediting a person as the VP for a track when that person did not provide the final vocal percussion performance. Of course, in modern recordings, all performances are edited to a degree. EQ is added; timing is corrected; parts are sweetened. There is no bright line test here, but if the vocal percussionist would have no chance at all of sounding even remotely like the recording, that should raise some concerns over simply crediting him as VP on the track.

Reprinting the Lyrics of the Song
Unless the song is in the public domain, or you have the explicit permission of at least one of the composers to reprint or display the lyrics, then don't reprint the lyrics. Even assuming you have properly paid your compulsory licenses, this does not include the right to reprint the lyrics. 

The two most common situations in which you would reprint the lyrics are 

1. When the lyricist is personally known to the group, such as a group member, and gives permission (preferably in writing); and
   
2. When the song is in the public domain [Amazing Grace]
   

(Note: under copyright law, the term composer is used to refer to both lyricists and musical composers.)

Translating the Lyrics of the Song
Printed translations of foreign lyrics into English require permission unless the song is in the public domain. This is particulary frustrating since readers love to see translations, and benefit greatly from reading them. Thankfully, it's perfectly acceptable to include a short summary that captures the mood of the piece and explains the story. 

Imagine that the TV cartoon song, "Scooby Do" had been written in a foreign language. You could not simply write out the translated lyrics in your liner notes, but you could have written this: 

"Scooby Do is the lighthearted tale of a mystery-solving dog. The singer is looking for Scooby, reminding him that he's needed, that he shouldn't pretend to be injured just because he's scared, and that he'll be rewarded with a special snack for his help. Bribery and honor overcome fear as Scooby does indeed arrive to help, ready and willing."

Comments
In the middle of the 20th century, in the era of vinyl recordings, artists would often include commentary about their songs, regardless of the language in which they were performed. Sometimes the commentary would be from respected musicologists or critics, and sometimes the group itself would share their own thoughts. Some comments included technical analysis, historical details, amusing anecdotes or personal reactions. 

This practice has fallen out of favor, in part due to the smaller dimensions of CD inserts, the desire to limit the amount of paper used and money spent on CD inserts, and in part because digital files rarely carry such information. Artists also have access to publish their thoughts in other ways. 

If your group is leaning towards this, best practice is to carefully evaluate how essential, entertaining and relevant such notes truly are before including them. In general, it's best to let songs speak for themselves, at least in English. Allow the listener to draw her own conclusions as to a song's meaning. Groups may opt to include such commentary on their blogs, elsewhere on their websites or even in concert. 

However, if the comments are extremely well written, provide relevant and nonobvious information, and room allows, brave groups should feel free to include such comments in their liner notes.


General Credits
The next group of credits is usually placed in the general credit section, but it is not inappropriate to credit them per track. The decision as to where they belong rests with the layout artist who must weigh space considerations with how often a particular name repeats. In other words, if all tracks were recorded, mixed, produced and mastered at Evil Giant Studios by Marty Gasper, then this is more easily written once in the general credits section rather than repeated under each track. But if a separate studio mixed each track, you may find it more readable to include this information under each tracks' title.

Footnotes
Often an asterisk or footnote system is used where several studios or engineers, etc., work on the album or where each of them worked on more than one track. Perhaps tracks 1, 5 and 6 would be followed by an asterisk [*] with tracks 2, 3 and 4 followed by another symbol [∆]. At the bottom of the page would be [* Tracks 1, 5 and 6 recorded at Woka Woka Studios and engineered by Fozzy Bear]. Underneath that might be [∆ Tracks 2, 3 and 4 recorded at Green Studios and engineered by Kermit T. Frog].

Producers and Studios
Include all producers’ full names in alphabetical order, and the studio under which each produced the tracks. [Produced by Luke Skywalker for Rebel Alliance Studios and Darth Vader for Death Star Studios]. 

The producer is the individual who makes the final artistic decisions regarding elements like how much reverb to use, how and whether to remix a track or arrangement, or how heavily effected or processed certain elements of the track were. The producer may have also determined which songs to include, chosen the song order, altered the arrangements, and coached the performances of the singers. 

Many groups divide these tasks between musical directors, group officers and hired producers. Your written agreement with a studio may control who gets the credit for producing. Often co-producers are named, and in some instances, the credit,  "executive producer" is used to denote the producer with final authority, particularly if that authority extends to financial matters.

Engineers
All engineers’ full names should be listed alphabetically, preceded by “engineered by”. If the engineer is the person who is responsible for recording the raw, unaffected tracks, this is credited as "tracking by" or "tracked by". If the engineer is responsible for implementing the producer’s sonic ideas, this is often credited as "engineered by" or "mixed by". Often, in a cappella, the engineer and producer are the same person. In this case, best practice is to state that a track was “engineered and produced by" or "tracked, mixed and produced by". Although it is not best practice, it is also acceptable to simply say "produced by".

Editors
Often a specific type of engineer called an "editor" is used. This person is usually responsible for "cleaning up" raw tracks. Editors use software to correct pitch and rhythm inaccuracies. They may also remove unwanted noises, like an errant car horn or loud inhalation. They should be credited by their full names for the studio they worked for [Edited by Neo for Matrix Studios]. If one person is responsible for editing and also some other type of engineering, such as mixing or producing, then the "edited by" credit is often omitted. However, best practice is to fully credit all work. 

Mixers
Mixing is a type of engineering task that is closely related to producing. It involves setting the levels of all recorded parts and often involves setting all effects on all tracks. Where one person is the engineer and producer, best practice is nonetheless to credit mixing separately [engineered, mixed and produced by Snow White for Bad Apple Productions]. However, many engineer/producers simply omit either the mix or engineering credit. As stated above, best practice is to credit all roles. 

Note that producer credit is never omitted. 


Mastering
Mastering is an aspect of the album process in which the final mixes of all tracks are treated to have EQs, volumes, bass response and even occasionally reverbs that all work well together. The goal of mastering is to make a more cohesive album. Mastering is usually handled by a separate studio from the one that tracked and mixed the recording. Mastering studios have specialized equipment and the spaces in which they work require more precise acoustical treatments. 

Mastering credit should be provided as “Mastered by Bill Clinton for Blue Dress Productions”. 

Originally Performed By or OPB
The credit “Originally Performed By” or “Original Artist” or “in the style of” should be avoided. 

This credit became popularized in collegiate a cappella in the 2000s, ostensibly from the influence of karaoke song lists. Best practice is not to use any version of this credit. There are several reasons why: 

1. The credits are like a recipe. They tell us what ingredients are in the album. The music and lyrics come from the composers. The arrangement comes from the arranger. The performance comes solely from your group. 
2. Crediting the original performers is tantamount to admitting that you value mimicry over originality. 
3. The "originally performed by" credit is often inaccurate. Without research, a cappella groups frequently credit the performing artists responsible for most popular version or most recent version of the song, neither of which is necessarily the original performer of a song.
4. The original performer, unlike the composer, a cappella group, soloist or producer, has no legally recognizable interest in the a cappella group's track.
5. Non-a cappella musical performers almost never include this "credit". 
   
6. Other similar artforms also universally avoid this credit. Actors perform roles, not roles as performed by prior actors. As an example, in the 2009 Star Trek movie, Chris Pine is credited as performing the role of Captain James T. Kirk. He is not credited as performing the role of Captain Kirk, as performed by William Shatner. This is true despite Shatner having starred in the TV series, the cartoon and the prior seven motion pictures. The prior performer's fame is irrelevant. Pine is performing a role, not imitating a prior actor. 

If you feel strongly about including some reference to other performing artists, consider crediting "inspired by" or "thanks to" or even "check out" . In the case of a highly imitative arrangement, you may credit your arrangement as based on the earlier work: [Arranged by Jane Smith, based upon the arrangement featured on "The White Album" as performed by The Beatles. © 1968].

As Performed By
Most of the comments regarding "originally performed by" apply to the credit "as performed by". Unless you are deliberately imitating the performance style of another artist, this credit should be avoided. 

Album Art and Photography
Album art and photography should be credited separately in the general section using complete names and associated businesses. Photographs are generally credited in text that is on or directly under the appropriate photos. If printed on the photo, and accurate, it is appropriate to use a copyright symbol (©) before the photographer's name.

P in a circle + Name + Date
I could make a joke here about what circular activities won’t get any name to give you a date, but I leave that to the reader. The symbol  ℗ means "copyright in the sound recording." It can also be written as "copyright in the sound recording" or  "© in the sound recording." 

Every track has two copyrights: 

1. the copyright in the composition, which consists of the melody and the lyrics; and 
2. the copyright in the sound recording, which consists of the fixation of the actual recorded sounds.
   

Typically the entity that makes the final decisions regarding the actual fixed sounds on the recording owns the copyright in the sound recording. 

This can get a little tricky when one person does this as a service for another, such as when a professional producer does this as a paid service for a group. This is best resolved in advance, and in a writing signed by the music director, the producer and anyone paying for or directing the means and methods of making the recording.

The sound recording copyright owner has the right to control when, if and for how much the actual recorded sounds of the album can be used in any other audio-visual works, any live or digital performance, in any physical copies and in any derivative works (such as samples, remastered versions, etc). 

Thanks
The general credits are the appropriate spot to thank supporters, parents, alumni, and even inspiring influences. This is a good place to thank the original artists, for those who feel personally inspired by them.

Abbreviations
When determining abbreviations, or shortened forms of names, clarity is key. Keep in mind that reviewers and awards committees prefer not to hunt through liner notes for critical information. For this reason, use complete names in all track credits, even where this involves repetition. Crediting only first names isn't as cute as it seems, and is only acceptable on albums in which the entire creative team is very small (such as a quartet), and then, only in combination with an exceptionally clear general credit section. In short, don't do it.


ID3 Tags
ID3 tags are the name for the metadata that accompanies, or more precisely, is embedded within digital music files. These tags are the equivalent of liner notes on physical discs. See this guide for metadata standards.

Name 
Put the exact song title here, making sure to keep capitalization and parentheses as originally notated. Do not add quotes or song numbers to this field.

Artist 
Put your group’s complete name here, as well as any featured or guest artists. For groups associated with schools, attempt to keep your complete name consistent. Are you the Northwestern University Overtones or The Overtones of Northwestern University? Is the "The" capitalized or not? Best practice is to use the complete name of your school rather than the abbreviation [NU]. On an album with multiple artists, put all artists performing on this track here just as you would in the liner notes.

Album Artist 
Put your group’s name here as one would find it in a music store or in a search query. On an album with tracks made by multiple artists, write “Various Artists” in this category. This is not the place to credit the visual artists that created your album art.

Album 
Put your album title here, making sure to keep capitalization and parentheses as originally notated. Best practice for multidisc releases is to write the album title then «space»(Disc «digit»). [The Good Time Singing Collection (Disc 5)]

Grouping 
This is often blank in contemporary a cappella music since it was intended to denote movements in a classical piece of music. However, if your group performs any musical work with movements in any genre, this is where you would enter that information.

Part of a Compilation (iTunes checkbox)
This box is checked in iTunes to indicate that tracks on an album were recorded by different artists. And yes, it is redundant if "various artists" is entered in the Album Artist field, but it's done anyway.

Composer
List all composers' complete names. Practice varies as to format. This was formerly done by last name, comma, first name, semicolon and then the next composer. [Minkoff, Jonathan; Feldman, Freddie]. However, today the more common practice is simply to enter the names. [Jonathan Minkoff and Freddie Feldman or Jonathan Minkoff, Freddie Feldman] What's critical is that the complete names are included and spelled correctly so that they can be searched.

Genre
There is ongoing debate as to whether a cappella should be recognized as its own genre. Some argue  against making a cappella a genre since it is more properly an instrumentation, and because stylistically, such a genre would encompass too broad a variety of music. 

As a practical matter, a cappella is not a genre on most music distribution services. Until that changes, this limitation ends the debate. When groups upload their album they must choose some genre, and so most groups choose the closest: pop, rock, r&b, jazz or easy listening, as they feel appropriate. 

I would argue that "a cappella pop" , "a cappella rock" and similar a cappella+ genres might be the best compromise, if such an option were made available. A search for just "a cappella" would turn up all a cappella genres, while one for "a cappella rock" would only return the subgenre. In the meanwhile, groups are at the mercy of the available options, though they can add genres to their own private iTunes collections, if they wish.

Year 
List the year the recording is completed. If this is a remix or remaster, and the field allows, it is appropriate to list the two completion dates: original and remaster, separated by a comma. If the field does not allow two dates, list the last completion date.

Track #
List the tracks in numerical order as they appear on the album. This will maintain the track order when played on digital devices.

Disc #
This two part field tracks the CD version of the album, but has diminished relevance in an all digital world. If your physical album is released on one disk then put 1 in both fields  If your album is a multidisc release then put the number of this track's disc in the first field followed by the total number of discs in the second field.

BPM
This stands for beats per minute. DJs find this information essential as their craft often requires them to match tempos when playing songs. If you hope DJs will play your tracks, this is good information to include. 

Comments
If your software doesn't permit additional specific fields, this one is the catchall. Use this field to add any information you possess about the track that does not have its own field. This will often include the producers, studios, arrangers and soloists. Character limitations may force abbreviations, but do what you can. 


Conclusion 
Credits don't need to be overly complex, just thorough and accurate. It's a good idea to make sure this part of the process isn't rushed as research requires time. Have at least one detail-oriented person proofread your work for typos. After all, these credits will last a long, long time!