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DIGITAL MEDIA REVIEWS

DIGITAL MEDIA REVIEWS
Haupt, Jon. Music Library Association. Notes69.1 (Sep 2012): 132-138.

The founding of Pandora Media in 2000, Rhapsody in 2001, Audio - scrobbler and Last.fm in 2002, and Apple's release of the iTunes Music Store in 2003 were among the most important steps toward the realization of a new market system. [...]although they applaud Spotify for using an open media format (Ogg Vorbis), anti-DRM activists decry Spotify for delivering the audio using a restrictive encrypted and proprietary way, disallowing certain activities that are alleged to be legal, such as taking an audio snippet from Spotify to use in a presentation or review.

This quarterly column offers reviews of free and fee-based music resources in a variety of digital media, including CD-ROM products, World Wide Web sites, online subscription services and databases, and music-related software of any kind. Some reviews may cover a number of related sources together. Excluded from this column are reviews of media in purely digital audio format that would normally be reviewed as sound recordings. The dates of access for each review of an online source indicate the dates during which the reviewer was evaluating the resource. All Web sites were last accessed to verify availability on 25 May 2012.

Spotify. Spotify Ltd. http://www.spotify.com/ (Accessed March 2012). [Requires Mac OS X running on an Intel processor, version 10.5.0 or later, or a PC running Windows XP or later. A broadband Internet connection is also required. Spotify is currently available in Austria, Belgium, Denmark, Finland, France, the Netherlands, Norway, Sweden, Switzerland, the United Kingdom, and the United States.]

The last fifteen years have been a period of massive change in the music industry. Although individuals had been sharing music for decades, the proliferation of relatively high quality compressed audio formats and mainstream peer-to-peer networking services-beginning with Napster- marked a completely new era and a clear need for new business models. While most individuals were willing to admit that simply giving copies of copyrighted music away presented a problem, by the time Napster had been shut down, the situation had already changed; listeners now believed that the cost of music had become too high given how simple distribution seemed.

In response to Napster and its many successors, new business models popped up far and wide. The founding of Pandora Media in 2000, Rhapsody in 2001, Audio - scrobbler and Last.fm in 2002, and Apple's release of the iTunes Music Store in 2003 were among the most important steps toward the realization of a new market system. Though heated discussion continues about whether an ownership model or a licensing model is better for artists, distributors, and consumers, the staggering number of users of the streaming services (Pandora now boasts some 80 million users) indicates that listeners are very supportive of this approach.

Founded in 2006 by Daniel Ek and Martin Lorentzon, Spotify is a music streaming service marketed to individuals. It is billed as a "legal and superior quality alternative to music piracy," with the stated goal "to help people listen to whatever music they want, whenever they want, wherever they want."1 Like its peers in the streaming audio service industry, Spotify offers a free ad-supported version and a premium monthly subscription service. Its name is derived from "spot" and "identify." Although the service has been highly successful in its European hubs, it is relatively new to the United States, having entered the market in July 2011.

Spotify is an enormously popular service with many facets, thus rendering the establishment of a scope for this review as especially important. The review will describe the content found in Spotify's database, remark on its subscription options, report on sound quality, and expound its functionality. There will also be a report on the active community of developers creating add-ons and applications (apps) for use with Spotify and the ever-growing mass of helpful user activity, such as playlist blogs. Spotify's possible effects on the market and on library patrons' expectations of service and content will also be considered. I tested Spotify using Mac OS X Lion (10.7) as well as the apps for Android and iOS (using an HTC mobile phone and an Apple iPad, respectively).

WHAT IS SPOTIFY?

Spotify is an audio player with an experience more like iTunes than its streaming music peers. Just as iTunes is an application that runs on one's computer, Spotify uses a downloadable client application for Windows and Mac, rather than a Web client. As of this writing, there is also a Linux preview version under development. Once the application is installed on a computer, getting started with listening is simple. A Facebook account is required in order to sign up with Spotify initially, but one can adjust how connected the two services are later. Spotify automatically begins importing MP3, MP4, M4A, and M4R files on the computer, but does not immediately display them. Instead, the first impression a new user receives is what's new in Spotify's catalog, as well as featured "Spotify Apps"- add-ons for Spotify, usually written by other companies. One can choose some new music from the "What's New" page or use the search box to find a particular piece of music.

Listening to music through Spotify is an experience much like that of using most other music players. The listener has the ability to change tracks, jump to a different place in the track, view other tracks in an album, shuffle or repeat tracks, etc. Ultimately, Spotify's most compelling feature may be the short time it takes for music to start playing once the user has made a music selection. As will be explained in more detail under this review's "Tech - nology" section, Spotify's unique system for retrieving tracks (briefly, a mixture of caching, peer-to-peer networking, and direct server download) results in a very fast response time-possibly faster than playing local computer files on a comparatively slow hard drive.

Unlike other streaming audio services such as Last.fm and Pandora, Spotify is not primarily a radio service (although some radio-like functionality is possible). Instead, the listener is allowed to choose any track at any time, within subscription level playback limits. Perhaps more importantly, anyone can create playlists, which can be used and modified again and again.

SPOTIFY'S CATALOG

Spotify's descriptions of the size of their catalog are reminiscent of McDonald's restaurants' longtime ubiquitous sign, "Millions and Millions Served." In addition to specifically noting the "millions and millions of tracks and albums," they boast that it would take "more than 80 years of nonstop listening just to get through it." They also say that they are adding 10,000 new tracks per day. Considering many sources, it seems that the catalog must contain somewhere between 13 million and 20 million tracks, probably leaning toward the high end.2

Spotify has a highly varied collection of tracks. With some notable artists missing from its catalog (they specifically mention Metallica, The Beatles, Pink Floyd, AC/DC, and Led Zeppelin), its strength lies more in variety than in comprehensiveness-but even in this category, Spotify seems at least on par with its peers. A particular recording of Beethoven's Moonlight Sonata, op. 27, no. 2 might be elusive, for example, but along with a few good recordings, one would find hundreds of remixes and adaptations. Within seconds, one can begin listening to a "Skytech Remix" of the sonata by Ashley Wallbridge, an electro-gothic arrangement by E.S. Posthumus, and several juvenile versions, such as "Bedtime Baby." Of course, this works in reverse-if a user would like to find a string quartet version of Lady Gaga's "Bad Romance," for example, or a classical piano arrangement of Coldplay's "Fix You," Spotify would be an indispensable resource. Someone looking for multiple versions of jazz standards is also looking in the right place-I was able to find over 100 unique recordings of "I've Got the World on a String" in 30 minutes.

With a stated goal of letting people listen to whatever they want to, whenever they want it, wherever they are, it is not surprising that Spotify seems to be constantly under pressure to explain why music is missing. Music librarians are probably already aware of the reasons why Spotify's catalog is not universal. While some artists and rights holders may be withholding tracks because of lack of interest in streaming media or fear of copyright violation, others avoid Spotify because they feel that their share of the royalties and advertising money is simply too low. Spotify's system pays royalties based on the number of times music is listened to, which makes it favor popularity in a very direct way; such a system is probably not for everyone.

PLAYLISTS

Playlists are the most important element of Spotify's functionality for users-they are used as a place to remember interesting tracks, learn about new music, and create mixes for experimentation and sharing with others. When a user identifies an album that he or she wants to listen to later, the user may add it to a "Starred" playlist, add it to a "Listen later" playlist, or create a new playlist. Users can create a customized playlist of tracks they like, order them in a particular way, and publish the playlist to share with the Spotify community. Users can follow playlists that have been published by others, and also subscribe to professionally- curated lists by various music sources, such as NPR's "The Ultimate NPR Workout Mix," or celebrity playlists by Barack Obama, Stephen Fry, or Tim Tebow.3 A user can also create "collaborative playlists" with one or more other people, syncing any changes made with all of the collaborators.

Adding and removing tracks to and from playlists is implemented using basic dragand- drop functionality. Because a playlist is basically the only way to remember tracks within the system, quickly amassing a large number of playlists is inevitable. A user can then find tracks that he or she has starred, imported, and bought, as well as those in custom playlists, through sidebar links. The user's "Library" is a conglomeration of all of these categories. The lists themselves can also become very large, so there is a secondary search "filter" option, displayed by default within the Library and Local Files sections. This filtering tool can also be conjured within any playlist, allowing pre- and post-filtering in searches-both options are valuable when looking for particular recordings.

Metadata in the Spotify system comes from dedicated external sources: MusicBrainz (track and album tags) and AllMusic (biographical information and images). In addition, a user can utilize Gracenote's track metadata to update his or her local tracks' metadata tags.

Spotify relies on user listening data for establishing associations between tracks (determining which tracks are "like" other tracks). Unlike the taxonomy used by services such as Pandora (in which tracks are associated through the use of curated Music Genome Project data), the listening data-driven method (also used by Last.fm) produces a folksonomy, or a system of associations created directly by a user base. This approach can produce some strange results, particularly when dealing with artists who are either very obscure (making it unlikely that there is enough data to provide meaningful associations) or very popular (perhaps listeners of super-popular artists simply listen to all popular music regardless of any specific music interests).

SUBSCRIPTIONS AND SUPPORT

Spotify has both free and subscriptionbased options. Spotify's free account (supported by audio and graphic advertising) offers six months of unlimited streaming, after which usage becomes more restrictive. Free account holders are then allotted two and a half hours per week of listening, which can accumulate to a maximum of ten hours, and individual tracks have an upper limit of five total listens. Free account holders also have the ability to use the Spotify application on their computer, providing a unified interface for all of their music. Local music can be played at any time, but tracks from Spotify's database are always streamed so listening to them requires a network connection.

The "unlimited" subscription service allows a user to continue unlimited streaming and also offers ad-free listening. At a higher cost, the "premium" service allows the listener to stream music at the highest quality available, sync playlists offline, and use Spotify from mobile devices, Sonos home audio systems, and other devices external to a computer.

While Spotify's downloadable application itself offers little to no support, a user with questions has a variety of other options. Support is offered through frequently asked questions in a Help section on the Spotify Web site. Some of the help pages are more like glossy guides, with more indepth explanations for essential tasks. Spotify uses official Twitter accounts to provide announcements and service updates to its user base. In addition, some Spotify employees answer questions on other external sites, such as Quora. Finally, Spotify users provide each other with help and tips, both through Spotify's forum community (http://community.spotify.com/) and on other Web sites.

TECHNOLOGY

In a saturated streaming music market, what differentiates Spotify from its peers? In short, Spotify excels at user control, device syncing, and speed. Unlike Internet radio, Spotify subscribers really can listen to whatever they want to (if it is in the catalog), whenever they want to. With various mobile devices, a Spotify subscriber can not only listen to tracks, but also make Spotify tracks available offline and combine them in playlists with their own music purchased elsewhere. The speed component is worthy of a full discussion.

Currently, Spotify's median latency (reaction time) for beginning a track after the play button is pressed is 265ms-similar to other near-instant services on the Web, such as Google Search. While the Web site and application are mostly flush with promotional material and actual content- with little explanation of the technology under the surface-Spotify's developers have provided some information in presentations and papers.

Radically unlike all of its Web-based music streaming peers, Spotify only gathers 8.8% (on average) of its data from Web servers. An additional 35.8% comes from peer-topeer networks, with the final 55.4% coming directly from locally cached data. When a user starts playing a track in Spotify, the track can immediately begin playing if the track is in the local cache. If not, it requests the first fifteen seconds of the track from Spotify's Web servers-just a small amount to start playing as quickly as possible. There is a complicated algorithm for determining when to start playing-a careful educated guess to balance latency with the possibility of stuttering. Once the track has started, Spotify combines the peer-to-peer network and its servers, jumping back and forth and taking data from multiple sources in order to piece together the file as quickly as possible. As track playback reaches the last thirty seconds, Spotify uses the peer-to-peer strategy to begin pre-fetching the data for the next track in sequence (61% of playbacks occur in a predictable order), so that it can continue playing seamlessly and further reduce load on the servers.4

Spotify's peer-to-peer networking strategy uses three approaches, providing a greater likelihood of success. First, there is a "BitTorrent-style" network tracker that has a pretty good idea of who has what music; second, there is a "Gnutella-style" query system for finding "neighborhood" peers; and finally, some data can be gathered directly from other computers in one's own local area network.5 All of these systems contribute to finding and downloading content quickly and seamlessly.

Given that all of Spotify's peers use a Web client, Spotify's insistence on using a native downloadable client is constantly scrutinized. Their response is uniformly that the native client has significant advantages that are currently unavailable to Web sites. Given that peer-to-peer networking provides their distinct technological advantage, the possibility of future Spotify Web services is probably tied to the ability to communicate with such networks using appropriate protocols.

Spotify's tracks are available at different sound quality ratings: 96 kbps, 160 kbps, and 320 kbps. All of the music uses the open source audio format known as Ogg Vorbis. The quality depends on the situation as well as availability-some tracks are not available in the highest bitrate.6 The highest rating is reserved only for premium subscribers playing from the desktop application; non-premium users and those using the mobile app are limited to the lower quality ratings.

It seems appropriate to compare Spotify's bitrate standard to the most popular library subscription services. Naxos Music Library currently provides streaming at up to 128 kbps to libraries. According to Alexander Street Press, the Classical Music Library service will soon offer streaming at 320 kbps.7 DRAM uses 192 kbps for streaming in all cases. If faculty and students make heavy use of Spotify and other similar services, it will be even more important for library subscription services to keep up with new standards, because user expectations will undoubtedly rise.

FUNCTIONALITY

Spotify includes a simple general keyword search box for locating music. It includes an autocomplete feature, meaning that after beginning to type, suggested results appear below the search box. Auto - complete results include "Top Hit" (perhaps Spotify's version of Google's "I'm Feeling Lucky?") as well as tracks, playlists, artists, and albums-with separators. A keyword search brings up results in all of these categories, presumably sorted by relevance. Relevance seems to be weighted in favor of track title, but popularity, album, and artist are clearly also used.

The search box is capable of far more complicated searches than is readily apparent. The Spotify Web site does provide a guide to advanced searching. The search box accepts Boolean searching. Parameter keywords can be used for more specific searching; artist, track, album, year, genre, and label are supported, as well as ISRC (International Standard Recording Code) and UPC (Universal Product Code). For example, "artist:Kissin" will return a list of results with Kissin as artist. The year param - eter can include ranges, as in, "year:1960- 1969." Phrase searching is allowed by using double quotes. For genre searching, Spotify has a little-known, automatically-generated list of genres in its system.8 Another feature that seems to have gone unmentioned on the Spotify Web site is the playlist parameter. A search for "playlist:shrimp," for example, returns a list of results in which the word "shrimp" is included in the title of the playlist.

The vastness of Spotify's catalog, along with an initial sorting by popularity,9 can present a problem when working with voluminous works comprising multiple versions, adaptations, and releases. Trying to find the original, unaltered version of Lady Gaga's "Bad Romance" using a basic keyword search, for example, will produce hundreds of results, including remixes or covers as well as multiple versions by Lady Gaga herself. Some releases are de-duped (not removed, but placed behind a "see more" arrow), but not all. "Original" versions do not receive special treatment for being original, so in many cases, they appear far down results lists. Just because one version happens to be popular does not mean it is the original version! De-duping can also be too comprehensive, such that original explicit song versions, as an example, can be lost in a sea of clean versions.

For classical music, the problem is even more apparent, mostly because there are a lot of voluminous works, but also because of music title confusion and overall lack of authority control. Popularity is unrelated to quality; if a poor quality recording is listened to a few times, it may be marked as more popular than a high quality version, thus becoming easier to find and compounding the problem.

Aside from looking through one's own library of music, the Spotify application itself does not provide much in the way of browsing access, other than the "What's New" section, browsing through friends' playlists, and looking through "recommended albums." It would be useful and fun to be able to browse through albums or artists by genre, year, etc.; this sort of functionality is probably what Spotify is hoping will be developed by other companies so that it can be included in Spotify in the form of an application. Some of the existing apps, such as Pitchfork, already provide additional browsing access.

Spotify's social networking features are currently a mixture of user connections within the Spotify system itself and connections drawn from Facebook friends. Social aspects of Spotify are more difficult to use without connecting one's account to Face - book. In order to connect with a user outside of the Facebook connection, one must either know the Spotify username of the intended person or search for his or her playlists.

All users have a "people" list, including Facebook friends with Spotify accounts (assuming the accounts are connected), and a manually curated list of "favorites." The People page also has an activity stream showing what users in the People list have been listening to. Users' profile pages show whatever content has been made public. New playlists are made public by default.

FURTHER DEVELOPMENT

Spotify's developer portal10 provides APIs (i.e., Application Programming Interface, which is a public interface for developers to create mashups and apps that work with Spotify) for dealing with music content, meta data, and the app infrastructure. Although most Web-based music services enjoy close connections with developers these days, Spotify's connections seem to be especially rich; perhaps Spotify's adoption of peer-to-peer networking systems helped solidify the company's stature among developers.

There are currently fifteen apps available in the Spotify client, two of which (Radio and Top Lists) are automatically included. Their purposes range from providing additional discovery and browse tools to providing a different listening experience, as with the Soundrop app. Using this app, users can collaborate and listen simultaneously with others. Users choose a "room" in which they and their friends vote on tracks everyone would like to listen to. Hopefully, future apps will be this creative in providing interesting ways to work with Spotify.11

To date, music libraries themselves have not publicized any formal uses for Spotify. So far, the only such use found in my search was a playlist of works to be performed that year in one institution's performing arts series. It will be interesting to see if music libraries will collaborate with each other or with their patrons to develop ways to provide services that utilize Spotify's content, or if faculty and students in aca - demic settings make use of Spotify without involving a music library or librarian at all-and, if so, what effect these initiatives may have on usage patterns of libraryprovided services.

CONCLUSIONS

Although Spotify is very popular, there are many reasons to be unhappy with it. Notwithstanding the compelling arguments for using a downloadable application, the lack of a Web client for Spotify makes it difficult for owners of cloud-based notebook computers (such as Chromebooks) to use the service because they are unable to install client applications. Other potential users balk at the requirement to tie one's Spotify account to a Facebook account, citing a general dislike of anything that requires a Facebook login. Yet more avoid Spotify out of solidarity with discouraged artists who are unhappy with royalty payment amounts. Finally, although they applaud Spotify for using an open media format (Ogg Vorbis), anti-DRM activists decry Spotify for delivering the audio using a restrictive encrypted and proprietary way, disallowing certain activities that are alleged to be legal, such as taking an audio snippet from Spotify to use in a presentation or review. Music is licensed, not purchased, in this case, making some legal arguments moot. This inspires questions familiar to many music librarians about the desirability of a licensing model in the first place.

In The Future of Music (Boston: Berklee Press, 2005), authors David Kusek and Gerd Leonhard imagine a future in which music is available to people in the same way water and electricity commonly are (at least for now, in some places)-through a small monthly fee paid by all. Spotify represents a form of this future. For additional revenue and to satisfy music aficionados, the industry should seek out additional revenue from personal connections to artists, extra textual and visual material, and other valueadded approaches. It remains to be seen where libraries fit into this scheme. Perhaps our focus will be first providing access to material not readily available; second, providing intermediation and research assistance; and third, providing excellent spaces for research and study.

It will be fascinating to see what the future holds for Spotify. As with the peer-topeer networks a decade ago, perhaps this service could be seen primarily as a way to attract new listeners. Given the service's plainly described aim of providing a lowcost, convenient, possibly better alternative to pirating music, their approach may be seen more as a sign of the times than as an attempt to change the market. The prevailing opinion of our times seems to be that digital music should be available practically for free, yet audiophiles continue to focus on analog media. With this in mind, not to mention the enormous continued interest in live music, it seems unlikely that one service will crush its competition. With highquality services like Spotify continuously improving and focusing on user experience, market competition, innovation, and debate are sure to continue.
Footnote

1. http://www.spotify.com/us/about/what/

2. http://www.spotify.com/us/about/music-catalogue-info/. Somewhat more specifically, the service offers "15 or 16 million tracks," according to CEO Daniel Ek in a recent interview with Evolver.fm (http://evolver.fm/2012/02/10/spotify-ceo-daniel-ek-talks-royalties-social-and-the-future/). Making this more complicated, though, Spotify's home page currently says "Over 13m songs are now yours to play." Perhaps they mean that 2-3 million tracks are actually different versions and releases of the same "songs," a scenario that actually seems likely, given the profusion of voluminous works available. Or perhaps thirteen million songs are available, along with two or three million instrumental works? Or is the home page simply out of date? The enthusiast Web site "The Pansentient League" has a "New on Spotify" page with new releases added in the previous seven days as well as its own "total tracks on Spotify" count that is updated daily. According to this resource, the database contains 19,682,555 tracks as of this writing (http://pansentient.com/new-on-spotify/).

3. There are several playlist-generating tools, as well, based on a user's parameters, including Spotibot (http://spotibot.com/) and Spotiseek (http://www.spotiseek.com/). Classical music listeners will be interested in Beijing-based Shi Lei's blog, Spotify Classical Playlists (http://www.spotifyclassical.com/), which also includes search strategies, discussions, and news items related to Spotify's classical music efforts.

4. Information on the technology behind Spotify can be found in presentations by Ricardo Vice Santos (http://www.slideshare.net/ricardovice) and articles and presentations by Gunnar Kreitz (http://www.csc.kth.se/~gkreitz/). There are also resources summarizing the information in the technical reports (http://pansentient.com/2011/04/spotify-technology-some-stats-and-how-spotify-works/).

5. Spotify: P2P music-on-demand streaming, http://www.slideshare.net/ricardovice/codebits

6. Researchers and audiophiles have discussed Spotify's bitrate claims at length, along with other audio quality concerns, such as embedded watermarks. Researcher Matt Montag has identified a watermark used by Universal Music Group that appears on all of its digital audio tracks, including those sold in "lossless" formats (http://www.mattmontag.com/music/universals-audible-watermark). While this problem is not limited to Spotify, it was curiosity about audio artifacts in Spotify tracks advertised at very high quality that brought on the discussion and ensuing research.

7. Alexander Street Press, Classical Music Library, http://clmu.alexanderstreet.com/help/view /audio_streaming_quality

8. http://www.spotify.com/us/about/features/advanced-search-syntax/genre-list/

9. Popularity is determined by how often a song is played-sort of. The Pansentient League offers a detailed explanation of Spotify's popularity algorithms (http://pansentient.com/2009/09/spotify-songpopularity/).

10. http://developer.spotify.com/

11. Resources are available externally for learning about building Spotify apps (Music Machinery, Building a Spotify App, http://musicmachinery.com/2011/12/02/building-a-spotify-app/) and for finding new apps that are on the horizon (The Pansentient League, Spotify Apps, http://pansentient.com /spotify-apps/#comingsoon).
AuthorAffiliation

Jon Haupt

Southern Methodist University
Word count: 4461

Copyright Music Library Association Sep 2012