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Erland Isaksson edited this page Dec 31, 2015 · 1 revision


Here are some casual descriptions of system users. They are not "actors" in the sense of Use Case actors, nor are they necessarily physical persons - at least not different persons. The same physical person can be Adam, Libby, Erica or Paul. But rarely at the same time (that would be schizophrenic ;-)

They are more meant to illustrate the "mindset" a person would have when doing certain tasks, loosely expressed in the spirit of a "Persona" ( Also, they are of course not meant to be specific, all-encompassing descriptions of the only users we expect. It's just examples, with lots of room for variation.

All these fictive users share the same SBS and SMD system. It's running on a server in the local network they share.

Adam the Administrator

Adam knows about computers since he uses them at work. Although not an IT professional, he is interested and skilled enough to install several computers at home. All family members have their own computer, and he has a local file server for sharing documents, photos, music and home video. This server runs SBS and SMD.

Adam is not particularly interested in music, he is the family's camera guy. He installs the system because his family wants to listen to music. Adam is not really interested in the system as such, he expects it to be easily installed and require very modest administration so he can keep editing his home videos. He wants the system updates to take place automatically (or at least easily), like most of today's applications.

Adam knows that the system is open source, and is prepared to go online to seek help on forums when problems occur. That's what he does with his video tools. But he really wants the system to run without ever touching it after installation.

Adam uses the operating system, a web browser and a text editor. To Adam, music is about disc size and bandwidth. He has heard of Michael Jackson, but thinks that AC/DC is something related to the power supply on the server.

Libby the Librarian

Libby likes music. But perhaps even more than music, Libby likes order and structure. Libby gets upset if two artists have the same name, or if nobody knows when an album was released. Or even worse, if there is no consensus on such a fundamental fact. The day Prince changed - or rather deleted - his name, Libby stayed home from work.

Over the years, Libby has used tag editors like MP3Tag or ID3TagIt to tag her files. She also uses MP3Gain to adjust the volume of all files.

With SMD, the tagging tools are no longer necessary; rather than tagging the individual files, she uses SMD to maintain this kind of metadata. The thing that Libby likes about this is that she no longer needs to modify the actual files, she can now assign the proper data for all files, even if they do not reside on her local disc. She still uses online reference libraries like MusicBrainz, freeDB and Discogs to get the data right, but she is no longer exposed to the risk of having all her precious tags corrupted by some malicious "autotagger".

For good reasons, Libby has formed her own opinion on the data quality of online resources, and chooses the ones she trusts the most. Since she uses freeDB for initial tagging when ripping files, she disables freeDB in SMD. When importing new files, she manually moderates additional metadata from MusicBrainz and Discogs. Libby is more interested in getting the hard facts right than the subjective opinions on genres. She is usually happy with the defaults suggested by MusicBrainz, but on occasion, she changes some tags. Since Libby's brother likes Metallica and AC/DC, he has forbidden her to tag Neil Young as "Hard Rock".

Using Libby's high quality meta data, Libby's brother can tell what each of all the Scotts and Youngs did on "Dirty Deeds Done Dirt Cheap", what albums the song appears on, when they were released, and on what labels. But Libby doesn't recognize the song on the radio. But since she has all metadata in order, Libby has asked the system to generate associations between all band members that also have solo careers (such as The Beatles, George Harrison, John Lennon, Plastic Ono Band, Paul McCartney and Wings). She has also generated links to all other constellations that band members appear in.

Libby gets satisfaction from a perfectly organized music catalog, without any contradictions or missing fields. She prides herself with having metadata that nobody knew existed (and nobody will ever use). Just for the joy of having it. In perfect order. And she loves the ability to play all tracks where John Lennon contributes in one way or another.

SMD loves Libby. Without Libby, SMD would not work.

Erica the Explorer

Erica loves music a lot. Erica also likes a lot of music. Erica is always on the quest for new music, and spends too many late evenings with the computer, browsing and previewing music, and categorizing them in playlists. Not to mention money.

Erica uses several online services and social networks to get new ideas, reading background data on artists and albums, and how critics and other people have rated them. Erica also reads the entertainment section of newspapers, both digital and traditional "paper papers". When Erica shops for music at online stores, she explores related music by associations generated by other customers. Whenever she finds something interesting, she "previews" the music in a software player. This is a crucial element for Libby; the effort of starting the preview must be very small, and if it takes too much time to start the preview, or at least to bookmark the artists for later, she loses interest. There's so much to read, and so little time to listen.

Music festivals are another source of inspiration for Erica. When she hears an interesting artist, she uses her mobile gadget to bookmark the artist for later. She adds the artist to her "scout" playlist on Spotify, and listens to all "discovered" artists on the way home. Upon arrival at home, she adds the newfound artists that stood the test to a new or existing playlist (or both). If she's really hooked, she tells her friends about her newfound love on Facebook. Some of her friends are not surprised, since they subscribe to her "scout" playlist.

Erica also spends a lot of money on subscriptions, digital downloads and physical CDs. She has well over a thousand CDs, but it's been years since she last mounted one in a CD player. She has ripped all of them. She still keeps all of her vinyl albums that she intends to sample "some time".

Erica uses social networks, commercial webshops and other music sites to explore new music. Erica is an active user of Facebook and Twitter, and has subscriptions with iTunes, Spotify and Last.FM. Erica is also a frequent visitor at AllMusic and a good customer with Amazon and other webshops. Erica uses software players like WinAmp and SqueezePlay when previewing and/or buying music from online music stores.

To be able to navigate and choose the right music for the right moment, Erica uses the power of the computer, the wisdom of the crowds and online ontology resources to maintain relations and large sets of playlists. Most of these are dynamically generated from metadata tags such as "genre", "style" or "mood", but she also maintains several static associations and playlists based on her own opinion. For instance, she has asked the system to generate associations between all band members that also have solo careers (such as The Beatles, George Harrison, John Lennon, Plastic Ono Band, Paul McCartney and Wings). She has also used AllMusic to generate associations to tribute bands, but decided to exclude associations for artists influenced by the Beatles (since Adam warned her about the disc space it would consume). She has manually added associations between AC/DC and AB/CD since the latter is a tribute band that seems unknown outside her home town.

Even though it was many years ago, Erica still remembers the frustration of exploring music in a traditional record shop where each record was classified in a single, specific category, assigned by some high-and-mighty unknown "expert". How silly. It was even hard to find a specific artist that you knew the name of, unless you also knew if the high-and-mighty unknown "expert" thought that this artist was "rock", "blues", "R&B" or "foreign".

Back in the vinyl days, Erica was the kind of hopeless nerd that would skip thru an album by playing only the solos since she could find them by looking at the texture of the record. Today, she spoils every party by never letting a song finish. Whenever something interesting plays, she jumps to another track - "you need to hear this too", until someone physically separates her from the remote control.

Erica maintains both dynamic and static playlist, and spends a lot of time arranging them for a divine listening experience. With all these associations and playlists in place, Erica can both find the right music for any given moment and explore new music at any given time. But since Erica finds so much new music all the time, she tends to get stuck with managing playlists rather than actually enjoying them. She seldom hears the same song twice, and she has rarely heard a complete album. And most of the music she listens to are previews on the computer. What a pity.

Erica is proud of her knowledge in music, and usually wins every music quiz she enters. She is recognized (at least among her friends and colleagues) as an expert in music. Erica gets satisfaction from the number of people subscribing to her published playlists.

Paul the Player

Paul plays music. At work, in the car, on the sidewalk and at home. At work, he keeps a backup of his entire music collection on a USB disc. In the car, he has a number of SD cards that plug into his car stereo system. He also uses a smartphone (iPhone or Android, depending on which he finds first) to play music, both from online services and built-in storage. At home he uses the smartphone or the remote control to play music thru his Squeezebox media player. Paul rarely touches a computer for music purposes other than buying music.

Paul usually knows what he wants to listen to: a specific artist, album or track, or a genre or playlist that someone else has prepared (perhaps Erica?). Paul is also interested in finding new music, but is not as active as Erica. Paul is interested in recommendations from a variety of sources, but he does not actively go music-hunting the way Erica does. Neither does he actively maintain playlists - he is vaguely familiar with the term, but not quite sure what it is used for. He knows he can follow suggestions presented on his player, save the interesting stuff in a place where he can find it later on, and is happy that it works.

Paul primarily wants suggestions when he is listening to music. Either music similar to what he is currently listening to, or based on his previous listening habits, or based on what his friends listen to at the moment. But he also wants distinct recommendations for completely new music from friends.

With a flick of the switch on the remote, Paul follows recommended links and can also save a track, artist or album to one of his favorite playlists. Online services, dynamic playlists, direct recommendations and subscribed playlists take him in ever new directions. With a flick of another switch on the remote, Paul also recommends cool stuff to friends, either by explicit recommendations on tracks, albums or artists, by sharing playlists, or by exposing "now playing" for SMD users in his social network.

One of the things Paul likes best is the ability to share what is now playing among his friends. Just as he can see what his friends are listening to, his friends can see what he is listening to. And with a tiny gesture, Paul can use this as a starting point for new explorations.

Since Paul discovers new music both at home and in mobile situations, he shares his musical preferences between his mobile gadgets and the system at home. When he finds something interesting on the way home, he wants to listen more on his home system. And vice versa, when he finds a new favorite at home, he wants to bring the music with him when he leaves for office.

Paul doesn't really care about computers. Paul gets satisfaction from listening to music. A lot. The neighbors will testify to this.

Claire the Classic

Claire is much like Paul in the sense that she primarily likes to listen to music. But where Paul is mostly interested in "modern" music, Claire favors classical music.

Due to the nature of the music, Claire uses other ways to browse and explore; things like "Conductor" or "Composer" matter to her. She even tags her music with catalog reference so she can verify when she buys music online if she already owns BWV1024. She had a hard work to clean all musical notation from french (si mineur) or German (h-Moll) to international notation (B minor).

Since Claire and Paul listens to different types of music, they have very different perspectives on the music collection. For Claire, all the stuff that Paul listens to is "Pop", whereas Paul considers AC/DC to be "Classical music".

Claire is very happy that she can browse the library in a different way than Paul. Most of her music is stored in a different location than Paul's, but she can browse his collection when she wants to, just as any other external music source. Only difference is that Paul's collection is local.

There are a few songs and artists in Paul's collection that Claire actually likes; she has selectively included some of Jon Lord's orchestral works and tagged it her own way. But she would never admit this to Paul.

When she builds playlists, she likes to add works (and not songs!) by period, type and instruments... she can't say if she prefers her playlist of romantic piano sonata or the one of baroque violin concertos.

John the Jazzer

John is much like Paul and Claire, but John listens almost exclusively to Jazz music. To John, the individual artists are vital, often more interesting than the bands they are or were members of. Bands come and go, artists stay - and appear in ever new constellations, often unique for a specific recording session. Some of the most interesting jazz music was recorded at jam sessions with a unique set of performers.

John likes traditional artists like Miles Davis, John Coltrane and Charlie Parker, but also follows the contemporary jazz scene with great interest. The number of talented jazz musicians in his local area is astounding. Since John's local area is not New York, the local artists are not very well known outside his region, and hence not listed in any major music repositories. John follows these artists thru web sites and paper magazines that focus on the local jazz scene.

John primarily explores music by tracing the career of an artist, finding other artists that he or she has collaborated with in one way or another. Unlike some of John's friends, he does not take much interest in exactly what horn Miles Davis played when or where, or who sat in on what session at Minton's Playhouse back in the old days. If he wants to know, he can google for it.

However, John is interested in knowing who played what on Miles Davis' Bitches Brew. This was in fact a major starting point that led him into a web that links more or less all jazz/rock fusion artists in music history: this is how he found Al di Meola, Larry Coryell, Jean-Luc Ponty and Marcus Miller, just to name a few. Although fusion is not his favorite style, and despite some of the trails take him into disgusting mainstream music, this newfound web will keep him busy and happy for several years. Without SMD and the ease of exploring trails in unknown directions, John may not have found it.

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