Jul 21, 2017 · 44m · y-combinator

Making Music and Art Through Machine Learning - Doug Eck of Magenta · Y Combinator

Doug Eck · 33m spoken Craig Cannon · 6m spoken
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In this Y Combinator podcast episode, host Craig Cannon interviews Doug Eck, lead research scientist for Google's Project Magenta, about leveraging machine learning to build open-source creative tools for musicians and artists. They discuss the technical evolution of generative sound and sequence models, the necessity of building intuitive interfaces for creators, and how AI serves as a collaborative partner rather than a replacement for human artistic catharsis.

How this conversation actually went

Every chapter scored 0–10 on four independent dynamics. Hover any point for the reasoning behind the score. How this is scored →

The partners as informed peer 2.8 Guest teaching 3.6 Guest disagreement 1.0 The partners pushing back 0.5
05100:0015:0030:000:23–2:41 · The partners as informed peer 3/10 Philosophical Framework and Machine Imperfections Craig introduces a thoughtful Brian Eno quote on artistic medium failure modes, prompting Doug to reflect on the division between research engineering and artistic breakage.2:41–4:45 · The partners as informed peer 2/10 Audio Generation and Sequence Models in Magenta Doug details NSynth and Magenta's architecture, walking through compressed latent spaces and the transition from basic MIDI RNNs to expressive, polyphonic models.4:45–7:12 · The partners as informed peer 3/10 Evaluating Machine Learning Models and User Feedback Craig asks how generative quality is evaluated; Doug candidly admits current evaluation is qualitative cherry-picking and jokes about building a viral collaborative filtering app.7:12–13:02 · The partners as informed peer 2/10 Developing Usable Tools for Musicians Doug explains why advanced producers like Aphex Twin gravitate toward NSynth's harmonic artifacts and temporal embedding decays rather than typical digital clipping.13:02–16:52 · The partners as informed peer 3/10 Interactive Performance and AI Duet Doug clarifies that AI Duet functions as an impulse-response improv partner for skilled jazz musicians rather than an autonomous long-form composer.16:52–20:38 · The partners as informed peer 3/10 History and Evolution of Recurrent Neural Networks Doug recounts working at IDSIA with Schmidhuber and Alex Graves, explaining how RNN breakthroughs were fundamentally enabled by scaled compute and massive data rather than algorithmic magic.20:38–23:07 · The partners as informed peer 3/10 Structural Challenges in AI Music and Caricature Generation The conversation covers model limitations in handling long-term musical hierarchy, noting how low-temperature sampling yields caricatures like the platonic Bach or average cat.23:07–26:20 · The partners as informed peer 3/10 Future Horizons: Narrative, Jokes, and High-Level Structure Doug explores high-dimensional narrative and joke construction, while Craig counters by suggesting generative models might first excel at formulaic airport pulp fiction.26:20–28:55 · The partners as informed peer 2/10 Public Reaction and Positioning AI as Creative Tools Doug dismisses alarmist claims that generative models harm humanity, framing AI systems as expressive artist tools rather than push-button automated replacements.28:55–31:26 · The partners as informed peer 3/10 Catharsis in Art Creation and Code Quality Doug discusses the emotional catharsis of creative coding and training models, comparing it to programming drum machines rather than merely playing preset loops.31:26–36:24 · The partners as informed peer 3/10 Reinforcement Learning and Rule-Based Steering Doug explains how deep Q-learning and reinforcement learning can steer pre-trained generative models with rule-based heuristic evaluators like counterpoint or line curvature.36:24–39:21 · The partners as informed peer 3/10 AI Impact on Pop Music and Cultural Adaptation Doug demystifies the fear of AI creating the single perfect pop song, arguing that cultural scaffolding shifts artists toward tackling new, harder forms of human expression.39:21–43:18 · The partners as informed peer 3/10 Long-Form Composition and Expressive Musical Timing Craig highlights Doug's earlier piano demonstration, leading into a discussion of Thelonious Monk's expressive timing and the need for fluid real-time MIDI APIs.0:23–2:41 · Guest teaching 2/10 Philosophical Framework and Machine Imperfections Craig introduces a thoughtful Brian Eno quote on artistic medium failure modes, prompting Doug to reflect on the division between research engineering and artistic breakage.2:41–4:45 · Guest teaching 4/10 Audio Generation and Sequence Models in Magenta Doug details NSynth and Magenta's architecture, walking through compressed latent spaces and the transition from basic MIDI RNNs to expressive, polyphonic models.4:45–7:12 · Guest teaching 2/10 Evaluating Machine Learning Models and User Feedback Craig asks how generative quality is evaluated; Doug candidly admits current evaluation is qualitative cherry-picking and jokes about building a viral collaborative filtering app.7:12–13:02 · Guest teaching 5/10 Developing Usable Tools for Musicians Doug explains why advanced producers like Aphex Twin gravitate toward NSynth's harmonic artifacts and temporal embedding decays rather than typical digital clipping.13:02–16:52 · Guest teaching 4/10 Interactive Performance and AI Duet Doug clarifies that AI Duet functions as an impulse-response improv partner for skilled jazz musicians rather than an autonomous long-form composer.16:52–20:38 · Guest teaching 5/10 History and Evolution of Recurrent Neural Networks Doug recounts working at IDSIA with Schmidhuber and Alex Graves, explaining how RNN breakthroughs were fundamentally enabled by scaled compute and massive data rather than algorithmic magic.20:38–23:07 · Guest teaching 4/10 Structural Challenges in AI Music and Caricature Generation The conversation covers model limitations in handling long-term musical hierarchy, noting how low-temperature sampling yields caricatures like the platonic Bach or average cat.23:07–26:20 · Guest teaching 3/10 Future Horizons: Narrative, Jokes, and High-Level Structure Doug explores high-dimensional narrative and joke construction, while Craig counters by suggesting generative models might first excel at formulaic airport pulp fiction.26:20–28:55 · Guest teaching 3/10 Public Reaction and Positioning AI as Creative Tools Doug dismisses alarmist claims that generative models harm humanity, framing AI systems as expressive artist tools rather than push-button automated replacements.28:55–31:26 · Guest teaching 3/10 Catharsis in Art Creation and Code Quality Doug discusses the emotional catharsis of creative coding and training models, comparing it to programming drum machines rather than merely playing preset loops.31:26–36:24 · Guest teaching 5/10 Reinforcement Learning and Rule-Based Steering Doug explains how deep Q-learning and reinforcement learning can steer pre-trained generative models with rule-based heuristic evaluators like counterpoint or line curvature.36:24–39:21 · Guest teaching 3/10 AI Impact on Pop Music and Cultural Adaptation Doug demystifies the fear of AI creating the single perfect pop song, arguing that cultural scaffolding shifts artists toward tackling new, harder forms of human expression.39:21–43:18 · Guest teaching 4/10 Long-Form Composition and Expressive Musical Timing Craig highlights Doug's earlier piano demonstration, leading into a discussion of Thelonious Monk's expressive timing and the need for fluid real-time MIDI APIs.0:23–2:41 · Guest disagreement 1/10 Philosophical Framework and Machine Imperfections Craig introduces a thoughtful Brian Eno quote on artistic medium failure modes, prompting Doug to reflect on the division between research engineering and artistic breakage.2:41–4:45 · Guest disagreement 1/10 Audio Generation and Sequence Models in Magenta Doug details NSynth and Magenta's architecture, walking through compressed latent spaces and the transition from basic MIDI RNNs to expressive, polyphonic models.4:45–7:12 · Guest disagreement 1/10 Evaluating Machine Learning Models and User Feedback Craig asks how generative quality is evaluated; Doug candidly admits current evaluation is qualitative cherry-picking and jokes about building a viral collaborative filtering app.7:12–13:02 · Guest disagreement 1/10 Developing Usable Tools for Musicians Doug explains why advanced producers like Aphex Twin gravitate toward NSynth's harmonic artifacts and temporal embedding decays rather than typical digital clipping.13:02–16:52 · Guest disagreement 1/10 Interactive Performance and AI Duet Doug clarifies that AI Duet functions as an impulse-response improv partner for skilled jazz musicians rather than an autonomous long-form composer.16:52–20:38 · Guest disagreement 0/10 History and Evolution of Recurrent Neural Networks Doug recounts working at IDSIA with Schmidhuber and Alex Graves, explaining how RNN breakthroughs were fundamentally enabled by scaled compute and massive data rather than algorithmic magic.20:38–23:07 · Guest disagreement 1/10 Structural Challenges in AI Music and Caricature Generation The conversation covers model limitations in handling long-term musical hierarchy, noting how low-temperature sampling yields caricatures like the platonic Bach or average cat.23:07–26:20 · Guest disagreement 1/10 Future Horizons: Narrative, Jokes, and High-Level Structure Doug explores high-dimensional narrative and joke construction, while Craig counters by suggesting generative models might first excel at formulaic airport pulp fiction.26:20–28:55 · Guest disagreement 2/10 Public Reaction and Positioning AI as Creative Tools Doug dismisses alarmist claims that generative models harm humanity, framing AI systems as expressive artist tools rather than push-button automated replacements.28:55–31:26 · Guest disagreement 1/10 Catharsis in Art Creation and Code Quality Doug discusses the emotional catharsis of creative coding and training models, comparing it to programming drum machines rather than merely playing preset loops.31:26–36:24 · Guest disagreement 1/10 Reinforcement Learning and Rule-Based Steering Doug explains how deep Q-learning and reinforcement learning can steer pre-trained generative models with rule-based heuristic evaluators like counterpoint or line curvature.36:24–39:21 · Guest disagreement 2/10 AI Impact on Pop Music and Cultural Adaptation Doug demystifies the fear of AI creating the single perfect pop song, arguing that cultural scaffolding shifts artists toward tackling new, harder forms of human expression.39:21–43:18 · Guest disagreement 0/10 Long-Form Composition and Expressive Musical Timing Craig highlights Doug's earlier piano demonstration, leading into a discussion of Thelonious Monk's expressive timing and the need for fluid real-time MIDI APIs.0:23–2:41 · The partners pushing back 1/10 Philosophical Framework and Machine Imperfections Craig introduces a thoughtful Brian Eno quote on artistic medium failure modes, prompting Doug to reflect on the division between research engineering and artistic breakage.2:41–4:45 · The partners pushing back 0/10 Audio Generation and Sequence Models in Magenta Doug details NSynth and Magenta's architecture, walking through compressed latent spaces and the transition from basic MIDI RNNs to expressive, polyphonic models.4:45–7:12 · The partners pushing back 1/10 Evaluating Machine Learning Models and User Feedback Craig asks how generative quality is evaluated; Doug candidly admits current evaluation is qualitative cherry-picking and jokes about building a viral collaborative filtering app.7:12–13:02 · The partners pushing back 0/10 Developing Usable Tools for Musicians Doug explains why advanced producers like Aphex Twin gravitate toward NSynth's harmonic artifacts and temporal embedding decays rather than typical digital clipping.13:02–16:52 · The partners pushing back 1/10 Interactive Performance and AI Duet Doug clarifies that AI Duet functions as an impulse-response improv partner for skilled jazz musicians rather than an autonomous long-form composer.16:52–20:38 · The partners pushing back 0/10 History and Evolution of Recurrent Neural Networks Doug recounts working at IDSIA with Schmidhuber and Alex Graves, explaining how RNN breakthroughs were fundamentally enabled by scaled compute and massive data rather than algorithmic magic.20:38–23:07 · The partners pushing back 1/10 Structural Challenges in AI Music and Caricature Generation The conversation covers model limitations in handling long-term musical hierarchy, noting how low-temperature sampling yields caricatures like the platonic Bach or average cat.23:07–26:20 · The partners pushing back 1/10 Future Horizons: Narrative, Jokes, and High-Level Structure Doug explores high-dimensional narrative and joke construction, while Craig counters by suggesting generative models might first excel at formulaic airport pulp fiction.26:20–28:55 · The partners pushing back 1/10 Public Reaction and Positioning AI as Creative Tools Doug dismisses alarmist claims that generative models harm humanity, framing AI systems as expressive artist tools rather than push-button automated replacements.28:55–31:26 · The partners pushing back 0/10 Catharsis in Art Creation and Code Quality Doug discusses the emotional catharsis of creative coding and training models, comparing it to programming drum machines rather than merely playing preset loops.31:26–36:24 · The partners pushing back 0/10 Reinforcement Learning and Rule-Based Steering Doug explains how deep Q-learning and reinforcement learning can steer pre-trained generative models with rule-based heuristic evaluators like counterpoint or line curvature.36:24–39:21 · The partners pushing back 1/10 AI Impact on Pop Music and Cultural Adaptation Doug demystifies the fear of AI creating the single perfect pop song, arguing that cultural scaffolding shifts artists toward tackling new, harder forms of human expression.39:21–43:18 · The partners pushing back 0/10 Long-Form Composition and Expressive Musical Timing Craig highlights Doug's earlier piano demonstration, leading into a discussion of Thelonious Monk's expressive timing and the need for fluid real-time MIDI APIs.

speaking balance: gold is the partners, purple is the guest (3 minute bins)

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Sharpest disagreement ▶ 26:45 Pushing back on AI alarmism

Doug firmly rejects the hyperbole that generative music is bad for humanity, contrasting moral panic with historical artistic shifts.

Hardest push from the partners ▶ 25:35 Reframing AI writing around pulp fiction

Craig challenges Doug's high-concept vision of complex joke generation by arguing AI is far better suited to formulaic airport novels.

Biggest teaching moment ▶ 17:10 The real driver behind deep learning breakthroughs

Doug educates on the history of LSTM, dispelling myths by clarifying that modern successes stemmed from compute and scale rather than brand new algorithms.

The partners hold their own ▶ 40:05 Referencing the Gray Area piano demonstration

Craig proves he thoroughly researched Doug's previous lectures, specifically citing his talk contrasting mechanical computer playback with human piano dynamics.

the scores for every segment, with the reasoning behind each
ChapterTopicThe partners as informed peerGuest teachingGuest disagreementThe partners pushing backWhy
Philosophical Framework and Machine Imperfections 3211 Craig introduces a thoughtful Brian Eno quote on artistic medium failure modes, prompting Doug to reflect on the division between research engineering and artistic breakage.
Audio Generation and Sequence Models in Magenta 2410 Doug details NSynth and Magenta's architecture, walking through compressed latent spaces and the transition from basic MIDI RNNs to expressive, polyphonic models.
Evaluating Machine Learning Models and User Feedback 3211 Craig asks how generative quality is evaluated; Doug candidly admits current evaluation is qualitative cherry-picking and jokes about building a viral collaborative filtering app.
Developing Usable Tools for Musicians 2510 Doug explains why advanced producers like Aphex Twin gravitate toward NSynth's harmonic artifacts and temporal embedding decays rather than typical digital clipping.
Interactive Performance and AI Duet 3411 Doug clarifies that AI Duet functions as an impulse-response improv partner for skilled jazz musicians rather than an autonomous long-form composer.
History and Evolution of Recurrent Neural Networks 3500 Doug recounts working at IDSIA with Schmidhuber and Alex Graves, explaining how RNN breakthroughs were fundamentally enabled by scaled compute and massive data rather than algorithmic magic.
Structural Challenges in AI Music and Caricature Generation 3411 The conversation covers model limitations in handling long-term musical hierarchy, noting how low-temperature sampling yields caricatures like the platonic Bach or average cat.
Future Horizons: Narrative, Jokes, and High-Level Structure 3311 Doug explores high-dimensional narrative and joke construction, while Craig counters by suggesting generative models might first excel at formulaic airport pulp fiction.
Public Reaction and Positioning AI as Creative Tools 2321 Doug dismisses alarmist claims that generative models harm humanity, framing AI systems as expressive artist tools rather than push-button automated replacements.
Catharsis in Art Creation and Code Quality 3310 Doug discusses the emotional catharsis of creative coding and training models, comparing it to programming drum machines rather than merely playing preset loops.
Reinforcement Learning and Rule-Based Steering 3510 Doug explains how deep Q-learning and reinforcement learning can steer pre-trained generative models with rule-based heuristic evaluators like counterpoint or line curvature.
AI Impact on Pop Music and Cultural Adaptation 3321 Doug demystifies the fear of AI creating the single perfect pop song, arguing that cultural scaffolding shifts artists toward tackling new, harder forms of human expression.
Long-Form Composition and Expressive Musical Timing 3400 Craig highlights Doug's earlier piano demonstration, leading into a discussion of Thelonious Monk's expressive timing and the need for fluid real-time MIDI APIs.

Statements from this episode (22)

Disclosure
Eck: Magenta aims to build creative tools, not act as artists
“The reason that I put that quote there, I think, is to be honest with the division between engineering and research and artistry, and to not think that what I'm doing is being a machine learning artist, but we're trying to build interesting ways to make new ki…”
Doug Eck Jul 21, 2017 ▶ 1:20
Insight
Eck: Users' first instinct with AI art models is breaking them
“The first thing you're gonna do, if you think, if someone comes to you and says, here's this really smart model that you can make art with, what are you gonna do? You're gonna try to show the world that it's a stupid model, right? But maybe the way that, maybe…”
Doug Eck Jul 21, 2017 ▶ 2:03
Assertion Supported
Eck: Google Magenta's NSynth cannot synthesize audio in real time yet
“Right now, it's quite slow to listen, so to speak. We're not able to do things in real time.”
Doug Eck Jul 21, 2017 ▶ 3:26
Opinion
Eck: Google Magenta's early music generation models were primitive RNNs
“We put out some models that were, you know, by any reasonable account primitive, I mean, kind of very simple recurrent neural networks that that generate MIDI from MIDI”
Doug Eck Jul 21, 2017 ▶ 3:54
Opinion
Eck: Magenta's generated AI music is not yet good enough for testing
“I, at least for Magenta, I haven't felt like the quality of what we've been generating has been good enough to bother, so to speak. Like you find it, you cherry pick, you find some good things, you're like, okay, this model trains, and it's interesting, and no…”
Doug Eck Jul 21, 2017 ▶ 5:08
Prediction Not checkable as stated
Eck: Artists will not do a huge amount with Quick Draw data
“I think, you know, I'm not expecting that artists really do a huge amount with this quick draw data because as cool as it is, These things were drawn in 20 seconds, right? There's kind of a limit to how much we can do with them.”
Doug Eck Jul 21, 2017 ▶ 9:43
Insight
Eck: Audio model generation errors sound musical because of learned training variance
“I think they're interesting because the model has been forced to capture some of the important sources of variance in real music audio, and even when it Fails to reproduce all of them when it fills in with confusion, so to speak. Even that confusion is, is som…”
Doug Eck Jul 21, 2017 ▶ 12:05
Assertion Supported
Eck: Google AI Duet relies on simple 2002 RNN technology
“And what I noticed, even with AI Duet, which is this like web-based, like, it's a simple RNN. It's like, I can lay claim. It's technology that was published in 2002. It's really a very simple, really simple.”
Doug Eck Jul 21, 2017 ▶ 13:16
Insight
Eck: AI music tools require strong human improvisation skills
“But if you don't have the musical, so basically it's the musician bringing all the skills to the table. Right. So like, even, even with the primitive sequence generation stuff, like it's still been interesting to see that it's musicians with a lot of musical t…”
Doug Eck Jul 21, 2017 ▶ 14:44
Disclosure
Eck: Magenta prioritized timbre generation over sequence generation
“I haven't, well, we haven't pushed the sequence generation stuff much because we really wanted to focus on, on tamper.”
Doug Eck Jul 21, 2017 ▶ 16:14
Opinion
Eck: Alex Graves advanced LSTMs more than anyone, including its creator
“Among the three of us, by far, Alex Graves has done the most with LSTM. So he continued, after he finished his PhD, and he continued doggedly to try to understand how recurrent neural networks worked, how to train them, and how to make them useful for sequence…”
Doug Eck Jul 21, 2017 ▶ 17:39
Insight
Doug Eck: Vanilla LSTMs cannot handle long-timescale hierarchical musical patterns
“Like LSTM in its most vanilla form, I think everybody's pretty convinced that it's not going to handle really long time scale hierarchical patterning.”
Doug Eck Jul 21, 2017 ▶ 20:45
Assertion Supported
Eck: Untrained listeners rated Magenta compositions as more Bach-like than Bach
“When we put these tunes out for, like, untrained listeners to listen to, they sometimes voted them as sounding more Bach-y”
Doug Eck Jul 21, 2017 ▶ 22:14
Insight
Eck: Low-temperature AI models produce caricatures rather than authentic samples
“If you sample from Sketch RNN with very low temperature, meaning with, like, without a lot of noise in the system, you actually get what, like, if you want to squint your eyes and break philosophy is like the platonic cat. You know, you get a cat that looks mo…”
Doug Eck Jul 21, 2017 ▶ 22:40
Assertion Supported
Eck: As of 2017, AI cannot generate a single coherent text paragraph
“So, so everybody understands that's listening or watching, you know, we can, we can't generate a coherent paragraph, right? So, I don't mean we, magenta. I mean, kind of we, humanity.”
Doug Eck Jul 21, 2017 ▶ 25:51
Insight
Eck: RL is slower to train than GANs but offers more flexibility
“So another way to do this is to use reinforcement learning. Yeah. And it, it's slower to train, because all you have is a single number, scalar reward, instead of this whole gradient flowing. Than GANs, but it also is more flexible.”
Doug Eck Jul 21, 2017 ▶ 32:54
Disclosure
Eck: Adding Deep Q-learning rules made Google Magenta's music noticeably catchier
“And we had, I thought, some very nice generated samples of music that were pretty boring with the LSTM network. But then the LSTM network trained additionally using a kind of reinforcement learning called deep Q learning to follow some of these rules. The gene…”
Doug Eck Jul 21, 2017 ▶ 33:51
Insight
Eck: AI will automate routine music creation, pushing artists toward new complexity
“Like some things that used to be hard will be easy. And so, We'll offload all of that. And if people are happy just listening to the stuff that's now easy, then yeah, it's a problem solved and we'll be able to generate lots of it. But then what people tend to …”
Doug Eck Jul 21, 2017 ▶ 37:57
Insight
Eck: Automating rhythm with drum machines enabled more complex human vocal phrasing
“So you've solved the metronomic, you know, beat problem. And then what you actually find is that artists who are really good at this, they play off of it and they're allowed like when they sing to do many more like rhythmical things than they could do before. …”
Doug Eck Jul 21, 2017 ▶ 38:16
Disclosure
Eck: Magenta aims to generate coherent long-form music and art
“I think composing, creating long form pieces, whether they're music or art, I think is, is something we want to do. And this hints at this idea of like, not just having these things that make sense at like, 20 seconds of music time, but actually say something …”
Doug Eck Jul 21, 2017 ▶ 39:27
Insight
Eck: Long-form ML models will let composers delegate macro structure
“If we get to models that can handle longer structure and nested structure, we'll have a lot more ways in which we can decide what we want to work on versus what we have the machine help us with, right?”
Doug Eck Jul 21, 2017 ▶ 41:00
Assertion Supported
Eck: Magenta has a core API enabling real-time MIDI AI collaboration
“I think the API, the core API that allows us to move music around in real time in MIDI, and actually have a meaningful conversation between an AI model and multiple musicians is there, and there's just a bunch more thinking that needs to happen, right, to get …”
Doug Eck Jul 21, 2017 ▶ 42:58
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