The following is a conversation with Gustav Sørenstrøm.

He's the Chief Research and Development Officer at Spotify, leading their product design, data technology, and engineering teams.

As I've said before, in my research and in life in general, I love music, listening to it and creating it.

And using technology, especially personalization through machine learning to enrich the music discovery and listening experience.

That is what Spotify has been doing for years, continually innovating, defining how we experience music as a society in a digital age.

That's what Gustav and I talk about among many other topics including our shared appreciation of the movie True Romance, in my view 1 of the great movies of all time.

This is the Artificial Intelligence Podcast.

If you enjoy it, subscribe on YouTube, give it 5 stars on iTunes, support on Patreon, or simply connect with me on Twitter at Lex Friedman, spelled F-R-I-D-M-A-N.

And now, here's my conversation with Gustav Söderström.

Spotify has over 50 million songs in its catalog, so let me ask the all-important question.

I feel like you're the right person to ask.

What is the definitive greatest song of all time?

So you can't speak definitively for everyone.

I wouldn't believe very much in machine learning if I did.

There is this song called You're So Cool, Hans Zimmer, soundtrack to True Romance.

It was a movie that made a big impression on me and it's kind of been following me through my life.

I sat with the organist and helped him play it on an organ, which was a pretty, Pretty interesting experience.

That is probably my, I would say, top 3 movie of all time.

And it came out during my formative years.

And as I've discovered in music, you shape your music taste during those years.

So it definitely affected me quite a bit.

Did it affect you in any other kind of way?

Well, the movie itself affected me back then.

I didn't really adopt any characters from the movie, but it was it was a great story of love, fantastic actors.

And and, you know, really, I didn't even know who Hans Zimmer was at the time, but fantastic music.

And so that song has followed me and the movie actually has followed me throughout my life.

That was Quentin Tarantino, actually, I think, director, director of produced that.

So it's not Stairway to Heaven or Bohemian Rhapsody.

They're not my personal favorites, but I've realized that people have different tastes and that's that's a big part of what we do.

Well, for me, I don't have to stick with Stairway to Heaven.

So 35,000 years ago, I looked this up on Wikipedia, flute-like instruments started being used in caves as part of hunting rituals, in primitive cultural gatherings, things like that.

Since then, we had a few folks, Beethoven, Elvis, Beatles, Justin Bieber, of course, Drake.

So in your view, let's start like high level philosophical.

What is the purpose of music on this planet of ours?

I think music has many different purposes.

I think there's certainly a big purpose, which is the same as much of entertainment, which is escapism, and to be able to live in some sort of other mental state for a while.

But I also think you have the opposite of escaping, which is to help you focus on something you are actually doing.

As I think people use music as a tool to tune the brain to the activities that they are actually doing.

And it's kind of like, in 1 sense, maybe it's the rawest signal.

If you, if you think about the brain as neural networks, it's maybe the most efficient hack we can do to actually actively tune it into some state that you want to be.

You can tell stories to put people in a certain mood, but music is probably very effective to get you to a certain mood very fast.

You know, there's a social component historically to music, where people listen to music together.

I was just thinking about this that to me, and you mentioned machine learning, but to me personally, music is a really private thing.

I'm speaking for myself, I listen to music, almost nobody knows the things I have in my library, except people who are really close to me and they really only know a certain percentage, just like some weird stuff that I'm almost probably embarrassed by.

Do you think of music as something that's social or is something that's personal?

It's the same answer that you use it for for both.

We've we've thought a lot about this during these 10 years at Spotify, obviously, in 1 sense, as you said, music is incredibly social.

On the other hand, it is your escape and everyone has these things that are very personal to them.

So what we've found is that When it comes to, most people claim that they have a friend or 2 that they are heavily inspired by and that they listen to.

So I actually think music is very social, but in a smaller group setting, it's an intimate form of, It's an intimate relationship.

It's not something that you necessarily share broadly.

Now at concerts, you can argue you do, but then you've gathered a lot of people that you have something in common with.

I think this broadcast sharing of music is something we tried on social networks and so forth, but it turns out that people aren't super interested in what their friends listen to.

They're interested in understanding if they have something in common, perhaps with a friend, but not just as information.

I was just thinking of it this morning, listening to Spotify.

I really have a pretty intimate relationship with Spotify, with my playlists.

I've had them for many years now and they've grown with me together.

There's an intimate relationship you have with a library of music that you've developed.

And we'll talk about different ways we can play with that.

Can you do the impossible task and try to give a history of music listening from your perspective from before the Internet and after the Internet and just kind of everything leading up to streaming Spotify?

There are some things that I think are very interesting during the history of music, which is that Before recorded music, to be able to enjoy music, you actually had to be where the music was produced, because you couldn't record it and time shift it, right?

Creation and consumption had to happen at the same time, basically concerts.

And so you either had to get to the nearest Village to listen to music.

And while that was cumbersome and it severely limited the distribution of music, it also had some different qualities, which was that the creator could always interact with the audience.

And also there was no time cap on the music.

So I think it's not a coincidence that these early classical works, they're much longer than the 3 minutes.

The 3 minutes came in as a restriction of the first wax disc that could only contain a 3 minute song on 1 side, right?

So actually the recorded music severely limited the, or put constraints.

I mean, constraints are often good, but it put very hard constraints on the music format.

So you kind of said like, instead of doing these, this opus on like many, you know, tens of minutes or something.

Now you get 3 and a half minutes because then you're out of wax on this disc.

But in return, you get an amazing distribution.

Without the mass scale distribution, there's a scarcity component where you kind of look forward to it.

We had that, it's like the Netflix versus HBO Game of Thrones.

You like wait for the event because you can't really listen to it.

So you like look forward to it and then it's, you derive perhaps more pleasure because it's more rare for you to listen to a particular piece.

You think there's value to that scarcity?

Yeah, I think that that is definitely a thing.

And there's always this component of if you have something in infinite amounts, will you value it as much?

So you're always seeking something you didn't have, and when you have it, you don't appreciate it as much.

But I think net, if you couldn't listen to music in your car driving, that'd be worse.

That cost would be bigger than the benefit of the anticipation, I think, that you would have.

So, yeah, it started with live concerts, then it's being able to, you know, the phonograph invented, right?

That you start to be able to record music.

So then then you got this massive distribution that made it possible to create 2 things.

I think, first of all, cultural phenomenons, they probably need distribution to be able to happen.

But it also opened access to, you know, for a new kind of artists.

So you started to have these phenomenons like Beatles and Elvis and so forth.

That were really a function of distribution, I think, obviously of talent and innovation, but there was also a technical component.

And of course, the next big innovation to come along was radio, broadcast radio.

And I think radio is interesting because it started not as a music medium, it started as an information medium for news.

And then radio needed to find something to fill the time with so that they could honestly play more ads and make more money and music was free.

So so then you had this massive distribution where you could program to people.

I think those things, that ecosystem is what created the ability for for for hits.

So you would tend to get these massive, massive hits, but maybe not such a long tail.

In terms of choice of everybody listening to the same stuff.

Yeah, and as you said, I think there are some social benefits to that.

I think for example, there's a high statistical chance that if I talk about the latest episode of Game of Thrones, we have something to talk about just statistically.

In the age of individual choice, maybe some of that goes away.

So I do see the value of like, you know, shared cultural components, but I also obviously love personalization.

And so let's catch this up to the internet.

So maybe Napster, well, first of all, there's like MP3s, tapes, CDs.

There was a digitalization of music with a CD, really.

It was physical distribution, but the music became digital.

And so they were files, but basically boxed software, to use a software analogy.

And then you could start downloading these files.

And I think there are 2 interesting things that happened back to music used to be longer before it was constrained by the distribution medium.

And then really the only music genre to have developed mostly after music was a file again on the internet is EDM.

And EDM is often much longer than the traditional music.

I think it's interesting to think about the fact that music is no longer constrained in minutes per song or something.

It's a legacy of an old distribution technology.

And you see some of this new music that breaks the format.

Not so much as I would have expected, actually, by now, but it still happens.

So, first of all, I don't really know what EDM is.

Yeah, you could say Avicii was 1 of the biggest in this genre.

So the main constraint is of time, something

have songs that were 8 minutes, 10 minutes and so forth, because, you know, it started as a digital product that you downloaded.

So you didn't have this constraint anymore.

So I think it's something really interesting that I don't think has fully happened yet, we're kind of jumping ahead a little bit to where we are.

But I think there's there's tons of formative innovation in music that should happen now that couldn't happen when you needed to really adhere to the distribution constraints.

If you didn't adhere to that, you would get no distribution.

So Björk, for example, the Icelandic artist, she made a full iPad app as an album.

Even though the app store has great distribution, she gets nowhere near the distribution versus staying within the 3 minute format.

So I think now that music is fully digital inside these streaming services, there is the opportunity to change the format again and allow creators to be much more creative without limiting their distribution ability.

It's surprising that we don't see that taken advantage more often.

It's almost like the constraints of the distribution from the 50s and 60s have molded the culture to where we want the 5, 3 to 5 minutes on that anything else, not just So we want the song as consumers and as artists.

Like, because I write a lot of music and I never even thought about writing something longer than 10 minutes.

That's really interesting that those constraints.

Because all your training data has been 3 and a half minutes.

So I think you had this file then that was distributed physically, but then you had the components of digital distribution and then the internet happened and there was this vacuum where you had a format that could be digitally shipped but there was no business model.

And then all these pirate networks happened.

Napster and in Sweden, Pirate Bay, which was 1 of the biggest.

And I think from a consumer point of view, which kind of leads up to the inception of Spotify, from a consumer point of view, consumers for the first time had this access model to music where they could, without kind of any marginal cost, they could try different tracks.

And that was a fantastic consumer experience to have access to all the music ever made, I think was fantastic.

But it was also horrible for artists because there was no business model around it.

So the user need almost drove the user interface before there was a business model.

And then there were these download stores that allowed you to download files, which was a solution, but it didn't solve the access problem.

There was still a marginal cost of 99 cents to try 1 more track.

And I think that that heavily limits how you listen to music.

The example I always give is, you know, in Spotify, a huge amount of people listen to music while they sleep, while they go to sleep and while they sleep.

If that costed you 99 cents per 3 minutes, you probably wouldn't do that.

And you would be much less adventurous if there was a real dollar cost to exploring music.

So the access model is interesting in that it changes your music behavior.

You can be, you can take much more risk because there's no marginal cost to it.

Maybe let me linger on piracy for a second.

Cause I find, especially coming from Russia, piracy is something that's very interesting to me.

Not me of course ever, but I have friends who have partook in piracy of music, software, TV shows, sporting events.

And usually to me what that shows is not that they're, they can actually pay the money and they're not trying to save money.

So what to me piracy shows is a business opportunity in all these domains.

Spotify stepped in is basically piracy was an experience.

You can explore, find music you like, and actually the interface of piracy is horrible.

And what Spotify does is basically first rewards artists and second makes the experience of exploring music much better.

The same is true, I think, for movies and so on.

Piracy reveals In the software space, for example, I'm a huge user and fan of Adobe products.

And there was much more incentive to pirate Adobe products before they went to a monthly subscription plan.

And now all of the said friends that used to pirate Adobe products that I know now actually pay gladly for the monthly subscription.

I think it's a sign of an opportunity for product development and that sometimes there's a product market fit before there's a business model fit in product development.

And in Sweden, I think it was a bit of both.

There was a culture where we even had a political party called the Pirate Party.

And this was during the time when, when people said that, you know, information should be free.

It's somehow wrong to charge for ones and zeros.

So I think people felt that artists should probably make money somehow else and, you know, concerts or something.

So at least in Sweden, it was part really social acceptance, even at the political level and that, but that also forced Spotify to compete with, with free, which, which I don't think would actually could have happened anywhere else in the world.

The music industry needed to be doing bad enough to take that risk.

And Sweden was like the perfect testing ground.

It had government funded high bandwidth, low latency broadband, which meant that the product would work.

And it was also there was no music revenue anyway.

So they were kind of like, I don't think this is going to work, but why not?

So this product is 1 that I don't think could have happened in America.

The world's largest music market, for example.

Because that's an interesting world of the internet where most people don't like to pay for things.

So Spotify steps in and tries to, yes, compete with free.

1 is people are starting to pay for things on the Internet.

I think 1 way to think about it was that advertising was the first business model because no 1 would put a credit card on the internet.

Transactional with Amazon was the second and maybe subscription is the third.

And if you look offline, subscription is the biggest of those.

I think people are starting to pay, but definitely back then we needed to compete with free.

And the first thing you need to do is obviously to lower the price to free.

And the way that Spotify was better was on the user experience, on the actual performance, the latency of, you know, even if you had high bandwidth broadband, it would still take you 30 seconds to a minute to download 1 of these tracks.

So the Spotify experience of starting within the perceptual limit of immediacy, about 250 milliseconds, meant that the whole trick was it felt as if you had downloaded all of Pirate Bay.

And it was still free, but somehow you were actually still being a legal citizen.

That was the trick that Spotify managed to pull off.

So, I've actually heard you say this or write this, and I was surprised that I wasn't aware of it, because I just took it for granted.

You know, whenever an awesome thing comes along, you're just like, oh, of course it has to be this way.

That's exactly right, that it felt like the entire world's libraries at my fingertips because of that latency being reduced.

What was the technical challenge in reducing the latency?

So, there was a group of really, really talented engineers.

1 of them called Ludwig Stregius, he wrote the, actually from Gothenburg, he wrote the initial, The Utorrent client, which is kind of an interesting backstory to Spotify, you know, that we have 1 of the top developers from BitTorrent clients as well.

So he wrote Utorrent, the world's smallest BitTorrent client.

And then He was acquired very early by Daniel and Martin, who founded Spotify, and they actually sold the Utorrent client to BitTorrent, but kept Ludwig.

So Spotify had a lot of experience within peer-to-peer networking.

So the original innovation was a distribution innovation, where Spotify built an end-to-end media distribution system.

Up until only a few years ago, we actually hosted all the music ourselves.

So we had both the service side and the client.

And that meant that we could do things such as having a peer-to-peer solution to use local caching on the client side, because back then the world was mostly desktop.

we could also do things like hack the TCP protocols, things like Nagel's algorithm for kind of exponential back off or ramp up and just go full throttle and optimize for latency at the cost of bandwidth.

And all of this end to end control meant that we could do an experience that felt like a step change.

We don't host our own stuff And everyone is really fast these days.

So that was the initial competitive advantage.

But then obviously you have to move on over time.

That was in 2008, the product was launched in Sweden.

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Gustav Soderstrom: Spotify | Lex Fridman Podcast #29