Friday, August 24, 2007

Station Reviews: Two for t-mobile and One for BlackBerry

@Home Radio* (click to play) This station offers recent light rock from four artist seeds and one song seed. Both of these stations created for t-mobile feature a few thumbs-up and, remarkably, a few thumbs-down. It's rare to see any thumbs-down on a promotional station. The few of us who used to talk about such matters over at Pandora Stations conjectured that the station builders do not want to give the impression that their client dislike a particular artist. To me the presence of thumbs-up and down just mean that someone actually spent a little time listening to the station. In this case they probably did not listen long (3 up, 2 down), but, at least they listened which makes the development of this station better than most promotional stations.

As for the results, the station is mostly harmless. I must say, however, I am happy to be listening to a nice cover of Cat Steven's "Trouble" by Elliott Smith while I write this review. I'd say the station is one of the better promotional stations, though it still doesn't come close to being is good as an average station built by a Pandora fan who has learned the value of providing feedback.

On-The-Go Radio (click to play) This station puts out danceable Electronica from three artist seeds and four song seeds. As mentioned above, the station has had at least a minor amount of development featuring one thumb up and three thumbs down. The station is reasonably energetic, but I find this side of the genre repetitive, almost wholly unmelodic, and the rhythm tracks, in particular, predictable and annoying.

BlackBerry presents John Mayer Radio* (click to play) You can create the exact same station by clicking on "Create a New Station" and typing in John Mayer. The people in charge of creating stations for ads do this occasionally, and I completely fail to see the point. (Yes, John, it does piss me off - the station is playing Mayer's "Back to You (Live 2003)") I know that the advertisers want to associate themselves with particular artists, but from the point of view of a Pandora listener, these simple stations with no development what-so-ever add no value at all to the Pandora experience. Why would I want to click through to hear a station I could make for myself in an instant? That being said, I am listening to another nice cover on this station: Jeffery Gaines is doing Peter Gabriel's "In Your Eyes".

Tuesday, August 21, 2007

Station Building 101: Twiddling Your Thumbs

Every time a song comes up on a station, the diligent curator has four choices: thumbs-up, thumbs-down, move it or leave it be. Because I like a wide variety of music, my ideal is to have many tightly focused stations, and use Quickmix to bounce between them. Thus, I have a different goal my mind for each station, and I attempt to use the thumb-decision to improve the focus toward that goal over time.

Frequently, the goal for my station is a genre. The stations that I am currently actively curating cover the following genres: Progressive Rock, New Age, Folk, Bubble Gum, Techno, Ska, Celtic, Early Electronica, World-Music tinged Electronica, Rockabilly and A Cappella. For these stations I use thumbs-down to weed out tracks which I do not consider to be in the genre, thumbs-up to tracks which are exemplars of the genre, and I leave alone those songs that are near a border of the genre, but I would not mind hearing again.

Other stations have a much more diverse range of goals. The goal for The Best Medicine is songs that make me laugh. The goal for Pagan Pride is music that addresses themes of concern to the Neo-Pagan movement or by explicitly Neo-Pagan bands. Pretty Pop Princesses is supposed to generate pop songs by female lead vocalists (I give thumbs down to any male lead vocals). Grrrl Power covers edgier, punkier girl groups, but if a kicking guy group plays, I leave it be. My Ren Faire station focuses on a small sub-genre of folk-rock influenced by early music.

The further these goals are from the information which is captured by genomes, the more frequently the station will stray from the desired goal of the station. For instance, I include as seeds for The Best Medicine all of the available tracks by The Shaggs because their music always makes me laugh. But none of the tracks that the genome identifies as close to those of The Shaggs is remotely bad enough to be funny the way those of The Shaggs are. Thus, I know that including the music of The Shaggs dilutes the focus of the station as a whole; nevertheless, it is important to me that their music crop up occassionally even though I must thumb-down virtual all of the other tracks in sets generated by them.

Frequently, as I explore the music coming from a particular station, secondary goals will arise. For instance, I try to keep Punk out of my Ska station. I don't dislike Punk, but I want my Ska station to play Ska as frequently as possible and there's a lot of Ska-Punk available on Pandora. Some Ska curators want to include that material, but I chose not to. The key to me, therefore, in that case is that I generally will not give thumbs-up to any tracks on that station which do not include

A tertiary and more subtle goal, in general, is to try to keep similar stations distinct from one another. My Loreena McKinnet station, my Celtic station, my Ren Faire station, my New Age station, and my Pagan Pride station are all somewhat close to one another. Thus, I also consider whether a given track would be more appropriate on another station and occasionally will move tracks as necessary.

An important part of keeping similar stations distinct is to follow the following simple rule: do not give thumbs-up to a track which is the seed of another station. In fact, if I create a new station, I will go to the station-page of adjacent stations, expand the thumbs-up list, and remove all the thumbs-up for tracks which are covered by the seeds of the new station. If I like a track, I generally do not mind hearing it coming from several stations, but I want that track drawing in new music on only one station.

Following this idea to its logical conclusion, I probably should attempt to insure that particular tracks are thumbed-up on at most one station. I have not done so, but it's the kind of project that I could see myself doing periodically.

Clearly, I do not listen to Pandora while actively attending to these standards all the time. But when I do click on the player page, these are the considerations which cross my mind as I consider the decision to thumb or not to thumb.

Sunday, August 19, 2007

Station Story: Dance Dammit

Over three months after creating my first station, I finally felt the need to create a second. The intent was to create a station that would play up-tempo dance numbers across a variety of genres. I put in four song seeds of some favorite songs with no real commonality other than the tempo.

This station taught me the lesson that Pandora is not good at isolating common traits between the suggested tracks. It did introduce me to Brave Combo, and Batmobile, but, overall, the station was a disappointment since not all the tracks were up-tempo. I stopped developing the station this past January after giving it an initial listening test.

Saturday, August 18, 2007

Is that Pandora in your pocket, or are you just happy to see me?

I thought that I had another year to go on my previous cell contract, but once Pandora had survived the deadline for royalty crisis, I checked to be sure. To my surprise, I was free to switch, and so I started getting Pandora on the Go a few weeks ago.

The first decision was which of the dozen available phones to choose. I started thread over at the Head-Fi forums eliciting any opinions about the audio quality of the possible phones. No one replied. And so I researched the phones over at Phone Scoop. The only significant difference in the specifications that I could see that might be relevant was that the Sanyo M1 had about 20 times the internal memory at one gigabyte than the other phones. Sprint had discontinued the phone a couple months ago (three or four of the phones listed by Pandora are discontinued), but several on-line merchants were still selling it.

All the phones required a two year contract, and you must have a Power Vision plan to have the unlimited internet time that Pandora requires. I went with the cheapest talk-time plan at $30/mo., and the cheapest Power Vision plan at $15/mo. A subscription to Pandora is also required at $3/mo. My previous plan was $40/mo., and so I'm spending about $8/mo. more to get Pandora everywhere Sprint can reach.

Unfortunately, Sprint's reach does not include my house. The nearest cell apparently ends about 100ft away from my driveway. Even with good reception, the PCS call quality is not as good as I was used to with T-Mobile. On the other hand, the customer service efficiently cleared up a set-up problem, and I like the operating system better than that which was on my T-Mobile RAZR. After the initial setting up, Pandora is just the push of two buttons away.

The M1 does connect and download swiftly. It comes with a 2.5mm (male) to 3.5mm (female) headphone adapter/microphone. However, the wire on the adapter is thin and a bit too long. I wanted a male-to-male adapter and ordered one from Crutchfield. Unfortunately, there is more than one kind of 2.5mm jack. Most cellphones have four contacts (left out, right out, microphone in, and ground) and most 2.5 mm adapters only have three. Using the wrong adapter means you'll only get sound out of one channel. I then purchased the one Pandora suggests, and it is shorter and sturdier. The remaining downside is that there are four connections between the phone and my ears: the 2.5 mm jack to the phone, the adapter to a lead, a lead to my head-amp, and the head-amp to my phones.

The sound quality is not as good as that from a computer. The M1, at least, has a noticeable amount of distortion, and particularly sibilant highs. The stereo definition and width of the soundstage are actually pretty good, though, even on the Sennheiser MX500 buds I use on the go. These audio problems are clearly the fault of the M1 since I use the same components through my computer at work, and the sound is definitely better on the computer.

A different audio problem is a fault of the Pandora player, however. Momentary interruptions of receptions can be heard as gaps in the music resulting in occasional blips and blurts. If you've ever had internet problems on your computer, you know that the Flash version of the player will almost always continue to the end of a song before it stops. That is, the Flash version uses the computer's memory to buffer the song in the background while the song is playing. The cellphone player does not buffer at all: when the reception stops, the music stops. I wish that the cellphone version of the player would avail itself of the available memory, but I must admit that the other phones have less than 50 megabytes to work with. (To compare, the Flash version requires 250MB to work at all.)

My only other complaint with the cell player is that when listening to your Quickmix, there is no display of which station a particular songs is coming from. I prefer to give my feedback in context of the station which is playing the song. That is, even if I like a particular, say, punk-pop song, I would like to give that song a thumb-down if it's coming from my Ska's The Limit station because I'm trying to weed out the ska-punk from that station.

In all other respects, the cell player is phenomenal. It was incredibly easy to set it up to access my Pandora account and stations. The interface is easy and intuitive, and it allows you to do everything the flash version does except edit your station pages (which I would not want to do without a thumbpad). One button is clearly marked thumbs up, another thumbs down. Skipping is the right direction button, reviewing the previously played songs is the left direction button, and changing stations is the up direction button. Extraordinarily clean and well designed. Great job, Tom.

And so each morning, I put on my buds, turn on the head-amp, and start the player. It loads as I drive down the hill, generally kicking in before I reach the first stoplight. The reception ends on BART under Oakland. I click the enter key to launch the player again when we emerge from the tunnel. I listen to another tune through West Oakland, and then lose the reception a second time in the Transbay Tube. As we pull into the Embaracdero I press the enter key again for the short walk to my building. I switch over to the computer when I'm at my desk. I switch back to the phone over lunch, and again when I head home. From 7:00 to 5:00 the buds are in my ears except for meetings and bathroom breaks. An unending, inter-venous connection to beautiful music. I love my mobile Pandora.

Thursday, August 16, 2007

Station Review: Malibu Barbardos Beach Radio*

One of the things that Pandora does is build stations for advertisers which are then incorporated into the ads that frame the player. I like to review these stations as they crop up. Because I now listen to Pandora on my mobile phone, I am now a subscriber. Subscribers do not normally see the ads, and so I asked Tom Conrad for the ability to do so, and he helpfully sent me this URL.

On deck today is Malibu Barbados Beach Radio (click to play). This station was built to sell a brand of coconut flavored rum. The station definition consists solely of 5 artists with no thumbs whatsoever. The bands work fairly well together with an up-to-date reggae, blues, indy feel. Nevertheless, as usual the lack of development is disappointing, and the station is below average even for the typical mediocrity of the advertising stations.

Wednesday, August 15, 2007

Station Building 101: Artists vs. Songs

I frequently use both artists and songs as seeds. I will use a set of consistently similar artists to form the base of station, and then add any individual songs by other artists of which I'm aware that might also fit the desired theme of the station.

However, one must be careful when adding songs as seeds to any station. The fact is that there are songs which have a Backstage page, and will come up as a positive result of a search, but which have not been analyzed and are not available for play on Pandora. When you add such a song, the Player behaves exactly as if you had added the corresponding artist to the station. And so the problem is that you may think you adding a single song which fits the theme by an artist who does not usually do that type of song while, in fact, you could be adding the entire otherwise irrelevant corpus of that artist.

In order, to verify that that a song is available for play, check its Backstage page and verify that it has a list of "Similar Songs". Of course, if you've already heard the tune on Pandra, then it's available for play and (modulo any rare cases where, say, a studio version has been analyzed but a live version has not) perfectly safe to add to your station.

Another advantage of artist seeds is that Pandora is constantly adding new music, and by using artist seeds you are much more likely to hear new music by that artist as it becomes available.

Sunday, August 12, 2007

Station Story: Ecclectica

On January 12, 2006 I read a story about Pandora in the East Bay Express. When I went home that night I created my first station. As I look at the dates for all the thumbs up I gave to the station during its ten-month life, I am reminded that when I first encountered Pandora I had no good way to listen to it. My house is a loft, and my computer shares a space with the living where my seven-year old generally watches TV in the evening. Thus, my first experience of Pandora was on the tiny, poor speakers of my home computer.

I had to have my Pandora after that first night, and so I quickly researched the world of Head-Fi, the audiophile approach to headphones. I decided to get Beyerdynamic DT880's for headphones, and a great, inexpensive head-amp, the Go-Vibe v3. (I got the 2nd-to-last v3 produced, and later I got a v4 for work and, now, the commute. Looks like the v7 will be the last that James Delgarno will produce. If you have any desire for a head-amp, buy this amp when it becomes available.). And so it wasn't until Feb. 11 when all the equipment was gathered that I was able to start listening to Pandora on a daily basis.

I started Ecclectica with songs by Cake, Madness, Puffy AmiYumi, and Dar Williams. The next month I expanded the range of the station even further with tracks by Orchestral Manoeuvres In The Dark, and Loreena McKinnet. That first day introduced me to The Sounds which means they were the first band I discovered with Pandora and later bought a CD. As you can see I like a wide range of music, and Ecclectica was the beginning of a beautiful relationship to Pandora.

The station eventually strayed further into reggae than I wished, but the eclectic range of the songs kept me quite happy until the advent of the Quickmix feature in October. I then disassembled it into several other stations, and kept it around only for the sake of nostalgia.

Saturday, August 11, 2007

Station Building 101: Getting Started

A good Pandora station is one which frequently plays music that you like. That goal is subjective, and, furthermore, the tools that Pandora provides to achieve that goal are indirect at best. Thus, particularly discriminating or compulsive listeners can find building a station in Pandora to be frustrating. With a little bit of understanding and patience it needn't be.

The first thing that you need to understand is that Pandora considers ALL aspects of the genome when assessing the similarity of tracks. That is, the player tends to weight fairly equally qualities like tempo, instrumentation, voice registry, lyrical content, and song structure. If you try to create a station which only focuses on any one of those qualities, you are pretty much doomed to failure. For instance, you could construct at station with every song you know that has a 5/4 time signature, and Pandora will almost completely fail to find other songs which have a 5/4 time signature.

On the other hand, because Pandora weights all these musical qualities fairly equally, it does a fantastic job at finding songs within fairly narrow genres. The reason Pandora works well for genres is that tunes within a genre tend to employ similar tempos, instrumentation, lyrical content and so on. Thus, a good place to start is to pick some genre you like and try to create a station for that genre.

You might think that using the smallest number of tracks as seeds for a station would result in the most focused station, but, unfortunately, if you look at the Backstage page for each track you add and do not agree that the six listed similar songs are what you are looking for, then you will not be satisfied with your station. If your station has few seeds, then you will hear the listed similar songs a lot.

Furthermore, pruning by thumbing down from a small set of seeds only results in a different small play-list from which the player will still deviate. One station builder added the individual track of Abbey Road and gave over three thousand thumbs down with no thumbs up, and was still giving thumbs down at the same rate as at the beginning.

For a station to work well there seems to be needed a minimum number of tracks as seeds and thumbs-up. I find that having at least four artist seeds is a good place to start, and if a genre is fairly homogeneous (like, say, Ska), then the more, the merrier.

If you do not know a lot of bands within the genre you're creating, you can generally find more by using Pandora's station search function to find what other listeners have grouped together. You will be looking for stations clearly focused the same genre. You will find some stations have every band and the kitchen sink (particularly the ones started prior to the release of Pandora's Quickmix feature), and you will need to ignore those stations. If you haven't heard of a band, it's generally a good idea to look at the Backstage artist page for the band to confirm that it is indeed within the genre.

Once you've got a good base of artists for your station, you will naturally discover other artists within the genre as you play the station. Be aware of scope creep, however. A single thumbed-up reggae track can infest your station with reggae (which is only a bad thing if you were aiming for some other genre). Do not be afraid to give a track a thumbs down even if you like it, if it does not fit the kind of music that you want the station to play as a whole.

And there you go. Pick four similar artists, add them to a station, and enjoy.

Friday, August 10, 2007

What we know about Pandora

How exactly Pandora works is, of course, proprietary information that helps keep Pandora in business by selling ads and subscriptions. Nevertheless, Tim Westergren (CEO) and Tom Conrad (CTO) have revealed bits and pieces of how the player works some of which is not widely known.

The Genomes The simple way to understand the Music Genome Project is that there is a set of traits which are assessed for each song in the database. More accurately, however, there are several such sets. The fact is that the initial genome did not make useful distinctions for certain genres like Electronica and Rap, and so they built more detailed genomes tailored to these genres as they entered into these genres. There is no genome for Classical music, and it remains unclear how high on the list of company's priorities is the creation of a Classical genome. Or, perhaps, it's proven particularly hard to create an effective genome for Classical.

The Focus Traits The traits listed on most song pages are NOT the genome traits. The listed traits are called "focus traits" and are calculated for each song after the genome traits are assessed for a track. The evidence is fairly clear that there is a different set of focus traits for each genome. For instance, Electronica tracks tend to list many more focus traits for each song than, say, a rock track. It also should be noted that around 5% of the songs which play on Pandora list no focus traits at all.

Song Assessment Pandora buys CD's to acquire the license to play the tracks of that CD on the player. However, when one of the trained Pandora musicologists tackles a CD they do not, in general, assess the genome for every song on the CD. Thus, even though a track may have a page in the database and even a sample, the track may not be available to play on Pandora because it's genome has not been assessed. If and only if a song lists "Similar Songs" on its page will that track be available for play on Pandora. The company will go back and add a song if enough people search for it; however, if one of your favorite tracks was passed over when they first covered a CD and that group does not have a following on Pandora, then it's unlikely that the track will ever appear on Pandora.

Song Selection The non-Quickmix player generates songs in sets of 3 or 4. The player appears to select a "keystone" song for a set from the list of the seeds (the Artists or Songs you selected for the station), the list of thumbed-up songs, or (rarely) one of the songs which are considered "similar" to one of the songs in those lists. The keystone can play in any position in the set (1st, 2nd, 3rd or 4th), and the other songs in the set will be particularly similar to that song (often these songs will appear in the list of "Similar Songs" for that song on the keystone's song page). Since June 20, 2007, the song selection algorithm has increased the chance that songs from the lists of seeds and thumbs-up will be among the additional songs in a set, and so it is more difficult to identify the keystones when listening. It appears that when a Quickmix plays several songs in a row from the same station, the songs are from an identically generated set of 3 or 4 songs.

Thursday, August 9, 2007

Links To Prior Posts

I've written several previous posts about Pandora on my main blog.


My first post about Pandora was an enthusiastic description of the service written a couple of weeks after I came across it. It's interesting that many of my technical wishes have been met, but the seemingly easier wish to build a community has not really gotten there. They have recently expanded onto facebook, but I'm sceptical.

Dr. Pandora Love

Pandora can make you confront your musical prejudices. I wrote this post in reaction to hearing a Cyndi Lauper tune on Pandora.

Shaggs on Pandora

I wrote a brief post on my delight that The Shaggs were available for play on Pandora. They have become a delightfully intractable part of my novelty station, The Best Medicine.

Pandora Shame, Pt. 2

Upon giving a thumb up to a Diana DeGarmo song, I begged forgiveness from the Lord. The track became one of the seeds of my Grrrl Power station.

Pandora Town Hall Meeting San Francisco, July 19, 2006

I attended a meeting with the Pandora folks, and wrote a thorough recap of the evening.

Pandora Town Hall, UC Berkeley, Dec. 4, 2006

I attended another town hall six months later, and provided another recap of the event.

July Listening Tests

I posted up a graph of my listening test results for the last six months. This graph shows the evidence that they made an important improvement to the selection algorithm in June. Indeed, I received an e-mail from Tom Conrad that they had made the change on June 20.

And that's all I've written so far in my blog on the topic.


Pandora is a free internet radio service that plays commercial-free radio which is tailored to your taste. Now that the fan community site has died, I've decided to start a blog to continue to talk about Pandora, and preserve some of what we have learned about building stations on Pandora over the last year and a half.