Below is a diagram showing a computer that can add one plus one to get two. It’s made out of an XOR gate and an AND gate, each of which is a relatively simple bunch of transistors wired together in particular ways. Transistors are just on-off switches that can be flipped electrically, so they have no moving parts (except electrons.) The beauty part is that the output wire of one transistor can be used to flip another transistor on and off.

The “numbers” in the diagram are just voltages: “zero” is zero volts, and “one” is (I think) 2.5 volts. The numbers in a computer are encoded in binary (base two) because it’s the most convenient way to physically realize them — voltage that’s pretty close to zero can be read as zero, and a voltage that’s pretty close to 2.5 can be read as one.
This simple adder has two input wires and two output wires. The input wires each represent a single binary digit, and the output wires together represent two binary digits. If one input wire has a voltage and the other doesn’t, the equivalent of adding one plus zero, the adder returns no voltage in the “twos” digit and a voltage on the “ones” digit. If there’s a voltage on both input wires, the equivalent of adding one plus one, the adder returns a voltage on the “twos” digit and no voltage on the “ones” digit, the binary number 10, or as we know it in decimal notation, 2.

Here’s a diagram of a four-bit adder, capable of adding numbers as big as sixteen. The diagram shows how adding seven (0111) plus twelve (1100) to get nineteen (10011) would work.
Wire together enough adders and other basic logic devices, set up at the right initial voltages, and you’ve got yourself a computer.

Original post on Quora

I grew up in the eighties. Cassette recorders were just starting to be ordinary household gear. My sister and I made a bunch of random tapes as kids, not knowing what we were doing or why, just that it was fun. We also taped songs we liked off the radio. We waited until the song we wanted came on, and then held up the tape recorder to the radio speaker. Go ahead and laugh, millenials, but this was such a widespread practice among my generation that there’s a whole Facebook group devoted to it.

Recording to a single-track tape from a single mic was the only way to record music until 1955. In the single-track era, music was recorded more or less the same way it was performed for an audience. There was a single mic in the middle of the room, and everybody played into it simultaneously. The only “mixing” was done by placing quieter instruments closer to the mic and louder ones further away. Recording as an art form unto itself came into being with the invention of multitrack tape, which made it possible to record different sounds non-simultaneously.

Multitrack is an enormously big deal for recorded music. It enables you to capture ideal performances more easily, since you record each voice or instrument in isolation from the others. An error on one track can be fixed while leaving the others intact. Multitrack also opened the door for mixing, since you can manipulate the volume and tone of each sound independently of the others. This might not seem like such a big deal, but that’s because we’re all so used to spectacularly high-tech sculpting of sound. When I listen to old jazz records, the bass is a vague muffled presence buried in the murk of the low end. It took until the sixties for recording engineers to really figure out how to make the bass jump out of the speakers; now we take for granted that it’ll be as crisp and defined as any other sound.

Even with all the flexibility it offers, tape recording is still relatively unforgiving. I recorded a few songs on tape with my first band in college. Correcting mistakes was tedious and took considerable skill and timing on the engineer’s part.

Since 1997 or so, everything I’ve recorded has been on the computer. There are some pros and cons. The major con is sound quality. Tape is analog. The waveforms it captures are infinitely smooth and continuous. By converting the continuous electrical signal from the microphones or instruments into digital files, you necessarily sacrifice some signal quality.

So that’s the bad news. For me, and for most recording musicians at this point, the good news enormously outweighs the bad news. Digital recording is cheap and constantly getting cheaper. Good quality audio tape is expensive; hard drive space costs next to nothing. A computer costs a heck of a lot less than a decent tape recording console and you can use it for other purposes. But cost is only the tip of the iceberg. The really big deal with the computer is that it visualizes music, turning it into screen objects that you can drag, drop and otherwise manipulate the same way you’d manipulate words in a word processing document. For a visual thinker like me, this is a transformative and revelatory change. It’s radically easier to do complex edits on the computer screen than keeping track of a bunch of pieces of identical-looking tape.

The other big deal about digital audio is perfect copying fidelity and endless editing. Every time you copy a tape, the sound quality degrades a little. Also, as tape ages, it chemically degrades. Digital audio files are highly robust. They’re just long lists of numbers, so you can copy them flawlessly and endlessly across any data storage medium. You can edit digital audio non-destructively, so you can try out ideas to your heart’s content without ever harming or losing your original tracks. Digital audio is also nice and portable. You can lay down basic tracks in your basement, overdub more sounds in someone else’s bedroom and then mix and master in a million dollar studio. And while there’s no undo with tape overdubs, you can effectively undo anything you do on the computer.

Music is intellectually a lot easier than it looks. The big challenge for me, and for most would-be musicians I encounter, is anxiety. We have a crippling fear of being judged, and when we’re doing a recording, the panel of potential judges is enormous. Digital recording has done a lot to reduce my anxiety in front of the microphone. Knowing that nothing is carved in marble takes a lot of the pressure off. I’m much likelier to lay down a perfect take or a cool new idea if I’m feeling relaxed, and recording in my apartment on a computer is as relaxing as it gets.

I’ve been recording an acoustic singer-songwriter’s album for the past year. Aside from the vocals and guitar, everything on the album is fake: the bass, the drums, the percussion and keyboards. The vocals and guitar are processed using Auto-tune, digital EQ and reverb and compression, and various other tricks. The “performances” are stitched together from many different takes, with sections repeated and individual notes corrected for timing and volume and decay. None of these techniques are unusual in the age of computer recording. Some people feel that the computer is harming musicianship by making it so easy to sculpt a flawless performance. My feeling is that the computer just shifts the locus of creative work from the original performance to the editing process.

After doing enough of my own projects using the full digital toolkit, I started questioning the wisdom of recording instrumental performances at all, when it’s so much easier to use sampling and synthesis. The turning point came while working with a soul/R&B band called Love Child. The singer and I were writing and arranging songs using samples, drum machines and all the other hip-hop tools. We gave these tracks to the band to teach them the parts. I made charts too, but the tracks were better for conveying the vibe and nuance we were after. We had a bunch of ace musicians in the band, but they never sounded as good as our sample-based tracks. We’d meticulously sequence a bassline, and then the bassist wouldn’t play it exactly. He’d do variations and little improvs, the usual embellishments that musicians add almost unconsciously. The problem wasn’t his ideas, they were all good. The problem was that by straying away from the extremely sparse parts we were writing, he was deflating the tension, turning our hip-hop feel into a generic-sounding funk.

So it went with all the musicians. Also, it was a logistical nightmare getting everyone together, and it cost a fortune. Eventually we asked ourselves, why are we doing this? The songs sound better on the laptop, why don’t we just commit ourselves to life in electronic world? So we started doing gigs with just the laptop and singers, and it sounded terrific. I feel bad for contributing to the rapid drying up of gigs all musicians are facing in the computer era. But meanwhile, we were going for a sound, and the human beings weren’t giving it to us.

Samples and loops give you a lot of freedom. They also carry their own constraints. When you use, say, two bars of a Miles Davis tune in a particular scale with particular chords to a particular beat played on particular instruments, that forces you to fit the rest of your musical elements to fit. This constraint is a stupendously valuable songwriting tool. Repeating the loop identically is easy and varying it is hard. So by default, sample-based music uses a lot of repetition, and you have to justify each variation because it takes so much more effort than another copy and paste. You’d think this would be true with live musicians too, but it’s not. Getting a band to play a loop without variation is just about impossible. I’ve tried many times, everyone gets bored or feels the need to express themselves. We in the western musical tradition undervalue repetition, and having the computer encourage it has improved my writing and arranging enormously.

Sampling is such a useful framework for structuring musical ideas, now I take a sampling approach to live recordings of instruments whenever I can. If I’m doing a rock track with Barbara Singer, we’ll record a take of her flailing freely away at the guitar over a beat, and then find the best bar or two and loop them. If we need a variation or another section, we’ll use the second-best bar or two, and maybe the third. The less material we use, the better it sounds.

In the future I would wish for a more porous barrier between the recording artist and the listener. It’s been a bottomless source of pleasure for me to remix and mash up other people’s recordings. With all due respect to my fellow musicians, I know what I like better than they do. For the vast majority of recordings I have, I’d rather hear the key musical ideas repeated identically in groups of four or eight over hip-hop beats. If recording artists don’t want to oblige me by structuring stuff that way, I can just edit their music to suit myself. It would be a lot easier to do this if I had access to the individual tracks. A few, very few, artists release tracks with the stems separated out. I wish for the day when it’s standard practice.

Update: for hilarious insight into the process of making a top ten hit in 1988, don’t miss the KLF’s Manual.

Part one:

Part two:

Part three:

Part four:

Part five:

Part six:

Steve Albini says that sampling is cheap and easy. He’s right about that. Anyone with a computer and a few pieces of inexpensive software can do it. Mr Albini also thinks people should be “embarrassed by sampling, like a bad dance move.” It’s a funny analogy, because while I like the albums he’s produced for the most part, they aren’t dance friendly. Pick any song that you’ve danced socially to in the past thirty years and the odds are high that it was produced electronically.

Anyway, in response to the charge that sampling is cheap and easy, why is that a bad thing? George Clinton points out that rock and roll was originally all about cheap and easy: three chords, repetitive beats and structures, singable choruses. Now, rock music is expensive and difficult, and thanks to people like Radiohead, every bit as technically inaccessible as jazz or classical. This is why rock has mostly become every bit as lame as jazz or classical. Making an art form expensive and inaccessible makes it elitist and conservative. The big artistic risks are mostly being taken by the electronic musicians, not the guitar tribe.

The documentary makes the intriguing analogy between DJs and photographers. DJs are to traditional instrumentalists as photographers are to painters. You can’t make blanket statements about the validity of the entire medium; you need to go on a case-by-case basis. DJs and photographers have a lower barrier to entry than cellists or painters but the path to mastery is every bit as long.

We’ve become accustomed to lavish production values in our recorded music, and that comes at a steep price tag if you want live instruments and analog tape. The expensiveness of lavish, dense live recordings forces conservative choices. The effortlessness of sampling leads to more risk taking, more experimentation, more innovation. Also more amateurish nonsense, but that’s the nature of the beast. A low penalty for failure is a necessary precondition for success.

Even if money is no object, there are still some strong artistic arguments in favor of sample-based music. The loop is different from a human playing a phrase over and over. I used to play in an R&B group. The singer and I wrote the songs with samples and loops and then taught them to the band. We had a Miles Davis sample that the trumpet player was supposed to use for his part. He played it pretty accurately, but never with the exact phrasing, tape compression and ambiance of the original loop, and it never quite sounded as good. It was cool that he could riff and improvise, but it gave us a looser, jazzier sound than we were going for. The identical repetition effects you to hypnotic effect. Check out the squealing trumpet sample under Public Enemy’s “Don’t Believe The Hype” – even James Brown couldn’t have that disciplined a horn player, not with all that insane noise swirling around. Humans get bored and distracted, they have opinions. Computers don’t. What if James Brown and band had been necessary to appear in person in order to create “Fight The Power”, and they had refused? What a loss.

The entertainment lawyer in the movie equates my sampling your song to me coming into your house, helping myself to the food in your fridge. Sampling might recontextualize old recordings in ways their creators find offensive, but very often sampled works add something of benefit to old recordings’ cultural standing. I’m thinking of all those classic seventies funk and disco songs with incredible beats but outdated lyrics and arrangements. George Clinton is outspokenly grateful to hip-hop producers for putting him back on the map, culturally and then commercially.

Meanwhile, the law is a serious obstacle. Clearing all samples in advance is crushing to the creative process, which depends on immediacy and spontaneity. It’s a lot cheaper and easier to get a license to perform or record a full cover of a song than it is to get the rights to a three second sample. Some copyright holders are laid back or indifferent, but some charge extortionate license fees. Erick Sermon had to pay Marvin Gaye’s estate a hundred thousand dollars for a sample clearance. Unless you’re a major pop star with serious backing, this is prohibitive, and we’re back to the conservatism imposed by high costs that plagues instrumental music.

Clyde Stubblefield’s reaction on first hearing how widely he was sampled: “Cool!” But he’s bitter about not getting credited. He’s not as upset about not getting royalties, maybe because he wasn’t getting those before sampling either – James Brown owns all the copyrights to “The Funky Drummer” and “Cold Sweat” and so on. Public Enemy explains they have to be secretive about their sources to not get sued. A healthier sampling culture would make it easy to use samples and encourage attribution and reasonable payments.

Sampling artists like to use the phrase “fair game” – I’ve used it myself to describe the contents of my iTunes library, and some of the musicians in Copyright Criminals use it too. What’s fair game? Depends. The Beatles are notoriously litigious copyright holders, but they themselves use unauthorized samples in “Revolution 9″, “I Am The Walrus” and “Tomorrow Never Knows.” I’m hopeful that as sampling moves from the fringe into the mainstream, the law will eventually catch up and the absurdities will iron themselves out.

Update: this post and another of mine are quoted in a Brands Plus Music post about the impact computers are having on music making. It’s a good one, thought-provoking, worth a read.

Lil Wayne and I have some differences of style and taste: about facial tattoos, about drinking cough syrup recreationally, about jewelry on one’s teeth. But we agree about music. He brags constantly that he’s the best rapper alive. I think he makes a pretty good case.

It wasn’t even Lil Wayne’s rhymes that caught my ear in the first place, it was his tracks. His music sounds fine on regular headphones or speakers, but it reveals its true power in the club or in a car with a good system. The tempos are slow, the beats are minimalist, and there’s plenty of space around every sonic event. On the big hits, like “A Milli” and “Lollipop”, an 8o8 kick drum is the only sound in the low register. There’s usually no bass guitar or even bass synth – the tuned 808 kick carries the bassline. The vocals, snares, hi-hats and synths are all up in the high frequencies. The midrange is totally empty.

Emptying the midrange adapts Wayne’s music perfectly to its natural habitat: cars, parties, clubs, subway trains and other noisy, less-than-ideal listening environments. In a club or a party, the midrange is full of people talking. In a car or train, the midrange is full of engine and wind noise. Keeping the music’s midrange empty means that it doesn’t have to compete with the ambient sound. The songs can sound huge and full and totally present without blowing your eardrums or your speakers out. Another benefit of the empty midrange is that it leaves room for you to enjoy the upper overtones of the kickdrum. Even severely compressed and played through computer speakers, Lil Wayne’s music sounds pretty damn hot:

The weird vocal sample the song is named for comes from “I Left My Wallet in El Segundo (Vampire Mix),” a remix of the Tribe Called Quest song by Fatboy Slim. The original Tribe song has a sample in it of “Funky” by The Chambers Brothers. That makes “A Milli” a remix of a remix of a remix. Recursive!

I’ve been drawn to the musicality of hip-hop since I was a kid, but at times I’ve been scared off by all the angry and confrontational language. As a kid, I could mostly enjoy with Run-DMC. Sometimes I found them a little bit scary, but mostly they made sense to me. My friend Elbert played me some Public Enemy in ninth grade, and I felt like it wasn’t meant for me, but I liked it. When we got into the nineties, that’s when I lost touch with hip-hop. I wanted to like the Wu-Tang Clan and the west coast gangsta rappers, but I got scared away.

It took me several more years to realize that I wasn’t supposed to be taking all the imagery literally. I didn’t understand that rappers, like rock singers, are often playing characters or doing standup comedy. It makes sense that Ice Cube has made such a smooth transition from gangsta rap to family comedies. Hip-hop has a lot of theatricality and irony to it, and even a liberal, open-minded white guy like me can lose sight of that. I fell into the bad habit of underestimating the intelligence of hip-hop artists and didn’t allow for the possibility of multiple or opposite meanings to what I was hearing. Imagine if you were plunked down in America without any cultural context and someone showed you an episode of South Park or Family Guy. If you didn’t realize they were kidding, you’d probably be horrified. That’s pretty much what my first reaction was to the dirtier hip-hop styles.

I’m glad I let go of my moral objections to Lil Wayne. He’s crude a lot of the time, but he’s never dumb, and he’s capable of dazzling verbal virtuosity. There’s the famous line in “Lollipop” that everybody quotes, it’s like what Cole Porter would be writing if he were a young guy right now:

Safe sex is great sex. Better use a latex,
’cause you don’t want that late text, that “I think I’m late” text.

Lil Wayne’s high opinion of himself extends to his choice of samples. He samples several of his own tracks for his song “I’m Me.” Again: recursive.

Like his frequent collaborators T-Pain and Kanye West, Lil Wayne likes singing with Auto-tune.

If you haven’t been listening to a lot of hip-hop lately, “Lollipop” represents the state of the art well. The synths are gridded out exactly in a sequencer so as to sound totally posthuman. Wayne plays a little electric guitar with a sloppiness that balances the synths’ unearthly perfection. There are big yawning digital silences in the rhythm that are as powerful as the beats themselves.

The Auto-tuned robo-vocal style inspired me to sing more on my own tracks, which is a minor miracle, because I am not a singer. The sign of a real master musician is when they fill me with an intense, competitive desire to go apply their tricks to some new music of my own.

I think Lil Wayne’s music is healthy for nerdy white people like me. Having a sense of humor about the human body and its functions is the right attitude. Natalie Portman kind of says it best, when she’s asked what song reflects her current state by Interview Magazine:

PORTMAN: Really, really obscene hip-hop. I love it so much. It makes me laugh and then it makes me want to dance. Those are like my two favorite things, so combined . . . I’ve been listening a lot lately to “Wait (The Whisper Song)” by the Ying Yang Twins, where the lyrics are like, “Wait ’til you see my dick” – which is just amazing because it’s whispered. [whispers] “Wait ’til you see my dick . . . ” [laughs] Crazy. So I just listen to it like I’m a five-year-old, like, “Oh my god! I can’t believe he just said that!”

When she rapped on Saturday Night Live, she was kind of kidding, kind of not.

In some ways this could be a Jewish thing. Like Natalie, my mom and the majority of my relatives are in the tribe. I went to a mostly Jewish elementary and high school. My Jewish side finds America’s puritanism weird and lame. I also have a midwestern protestant side I inherited from my dad. This side of me thinks prudishness is lame, but also Not Optional. So there’s some internal conflict. It can be like Jon Stewart vs Hank Hill in my head. Lil Wayne is a good ally in my struggle to keep Hank under control.

But then, Lil Wayne may have more in common with Hank Hill than we realize. He carefully cultivates the image of a stoned slacker, but that performance masks an intense work ethic. It’s significant that the “A Milli” video shows Lil Wayne doing his job. He records new material almost every night. I can’t think of any recording artist who’s been more prolific than he has. Almost everything he records, he makes public. Some of it gets sold commercially, the rest he gives away on mixtapes and the web. He puts out so many tracks that Vibe could write an article called “The 77 best Lil Wayne songs of 2007.” He talks about his process a little in Rolling Stone:

You never write down your rhymes. Do you ever forget good stuff?

I do that a lot and it sucks. That’s why I keep the studio with me everywhere I go. I can just hook up the studio straight to my laptop and start recording. I don’t memorize lyrics like a speech. I just go to the studio and think of it right there. I just let the beat play a trillion times and I go in there and record four bars or whatever I thought of so I can get it off my mind and start thinking about something else. That’s why I do my songs so quick.

I think any creative person could learn a lot from the Lil Wayne strategy. Computer recording encourages improvisation. Improvising is a bottomless source of new ideas. Creativity is evolutionary, you need to have a lot of failures to naturally select out the hits. The wider the diversity of your failures, the more hits you’ll produce. That’s why Michael Jackson and Quincy Jones recorded hundreds of demos so they could narrow them down into the songs on Thriller. Lil Wayne takes the idea up a notch by releasing everything for public consumption and letting the fans decide what works and what doesn’t. I’d guess this demanding routine keeps him from ever getting hung up, from getting too precious. He probably gets things right in a very few tries. Keeping your ideas under so much evolutionary pressure makes them definite. As Lil Wayne says in “Shoot Me Down”:

My picture should be in the dictionary next to the definition of definition.

He’s definite enough to have sampled the Beatles and gotten the copyright smackdown for it. (Thanks to Sasha Frere-Jones for pointing me to this.)

The comments on this video are hostile. I can understand not liking the music, but the anger is way more intense than that. I can’t imagine having so many people that angry at me. If Lil Wayne can keep his confidence up in the face of so much scrutiny and resistance, I don’t see how any creative person has any excuse not to step up their game.

Here’s my mashup of Lil Wayne and Björk.

Lil Wayne Is Oh So Quiet

To download, right-click or option-click the link and save the file to your desktop.

The Gregory Brothers (including a sister-in-law) are musicians here in Brooklyn who have a series of videos called Auto-tune The News. Here are a selection of their better episodes as of this writing.

The Gregory Brothers also produce straight R&B tracks. With all possible respect, I don’t find their serious music to be anything special. It’s when they submerse themselves in TV that they shine the brightest. The internet doesn’t have a lot of info about their production techniques, all I could find was an interview where Michael Gregory says:

Logic Express was a godsend for composition–it has an enormous sample library. I use it for all my audio now. For vocal processing, auto-tune and melodyne plug-ins come in super handy. I use Final Cut Express for all the editing, but the capture feature is somehow rubbish, so iMovie gets called in for that.

So there’s a lot of very sophisticated computer software at work, though with a charming zer0-budget lameness of video compositing and audio mixing. I imagine when they wind up on Comedy Central or wherever, the production values will get a little more slick.

Musically, these videos are working for me. If they slowed the tempos down and found some heavier kick and snare sounds, they’d be ready for the radio. I guess I shouldn’t be surprised. My own experiments with Auto-tune show any kind of human speech as pretty tonal to begin with. When you automatically tune someone talking to the closest piano-key pitches, it makes it easier to make out the melodies that were already present. The Gregorys do a lot of further manipulation and harmonizing, but their best moments come from unintended speech melodies, like Joe Biden shouting “God bless America”, from space.

Some languages are more tonal than others. Chinese uses pitch to differentiate words semantically, the way English uses combinations of vowels and consonants. The same string of phonemes spoken at different pitches in Mandarin might have completely different meanings as words. Even in English, we use pitch to communicate punctuation, emotional stance and other metadata. Read this out loud to see what I mean:

Okay?

Okay.

Okay…

Okay!

Speech has a lot of profound overlaps with music, to the point where it’s sometimes difficult to draw the line between them. This is I why I’m convinced by the theory that music is the evolutionary precursor of language, the bridge between monkey calls and our present communications systems.

By quantizing and digitizing information, you make it easier to memorize and replicate it. I find myself humming phrases from the Gregorys’ videos the way I hum Andrew Lloyd Webber. Digitized sound information is easier to memorize, store and copy. The subtle nuances of Katie Couric’s speech with all the pitches on a continuous spectrum are difficult to remember and imitate, but once it’s Auto-tuned, it becomes effortless. Digitizing data in any medium makes it much more robust across many generations of copies. DNA is a digital medium – the G, A, T and C of your genes can be logically expressed as ones and zeros, and ones and zeros can be replicated flawlessly and endlessly.

I find Auto-tune bottomlessly entertaining to listen to. Jay-Z and many of my friends say they’re tired of it, but I’m not. I can understand why you might be getting a little burned out on it if you listen to pop radio. However, there’s a lot of resistance out there to Auto-tune that’s too deep and intense to just come from jadedness with a music fad. The Time magazine article about the Gregorys allows that Auto-tune “isn’t always a way to cheat.” I find that funny. How can Auto-tune be cheating? How can you cheat at music? It’s not a competitive sport. I prefer to think of music as more like a game. You can play better or worse, but there aren’t really winners and losers. We’re adept at coming up with systems of rules for music, but we get carried away with that. Who cares how you make it so long as it sounds good?

If Auto-tune causes you distress because you care about authenticity in your music, I can understand that. I resisted “fake” music through most of my teens and twenties. Now I regret all the effort, but I guess I had a point. I was worried that someone was trying to put something over on me. I gave up my desire for authenticity after it became clear that it’s an impossible dream. There is no authenticity anywhere.

Ever since the sixties, we urban elites have fetishized the bluegrass of the forties as a pure folk form. But Bill Monroe wasn’t some naive backwoods hick. He designed his music deliberately for its commercial appeal to a particular audience. For instance, all that intense treble was there to cut through radio static and low-tech mics and mixing desks. This doesn’t make Bill Monroe’s music any less truthful or good. I commend him for finding a way to reach a mass audience with such idiosyncratic, regionally specific music.

I don’t think there’s anything magical or transcendent about good music. It’s like good food, if you make it with care and attention, then it makes people feel good. Sometimes you’re cooking for yourself, sometimes you’re cooking for anyone who walks in the door, sometimes you’re cooking for paying customers. It depends on the situation which recipes are going to work the best.

The half-life for “bad” inauthentic pop music to decay into “good” authentic art music seems to about one generation. The analog synths and drum machines that sounded so fake and lame in the seventies and eighties are cherished vintage gear today. Even the digital samplers of the eighties have attained authentic status because of the digital crunchiness you get from the low sampling rate. I’ll bet you anything that future hipsters are going to fetishize Auto-tune once the pop mainstream has safely abandoned it.

Potentially the most offensive but also the least ironic video by the Gregorys is this one:

Here’s the mp3 if you want to download it. It makes me a little uncomfortable, especially the greenscreened backup singer thing, which feels disrespectful. But I can’t argue with the message. I’d like to hear a producer with more chops do a version of this, maybe at a mellower tempo with less embellishment. Imagine turning on the news and seeing that speech. Either version.

There was no caption or any other context. So I posted it on my Flickr with a note asking if anyone could identify the computer Herbie is sitting in front of. A couple of days later my friend Mike responded with this video of Herbie and Quincy Jones demonstrating Herbie’s Fairlight CMI in 1983.

There’s so much to love about this clip, from the light pen interface onwards. Youtube doesn’t provide much context, so I don’t know who was shooting this or why. But I’m glad they did. Quincy poetically describes playing a synthesizer as “sculpting a pure electronic waveform.” The interviewer observes that the African blood is streaming through the electronics. Quincy laughs and says: “The funk will prevail.” Herbie laughs too, and then says probably the wisest thing I’ve heard anyone say about technology in music:

It’s interesting, cause you know, these instruments were designed for people to use, for people to use. It’s just a tool, another tool, the way an axe is a tool, an axe can be a tool to cut wood to build a house, or can be a tool to slaughter your neighbor… A synthesizer can be a tool to really hurt people’s ears or interfere with their lives, or can be a tool to make a really nice-sounding instrument that can affect people in a positive way. It all depends on the person who’s using it… The machine doesn’t do anything but sit there until we plug it in… It doesn’t program itself. Yet.

Herbie was acknowledging the angst that a lot of his fellow jazz musicians were feeling about synthesizers and other electronic music gadgetry (angst that hasn’t diminished in the years since.) Herbie titled his album of that year Future Shock for good reason. But ultimately, he’s right, the tools aren’t as important as the people behind them. You couldn’t ask for a better electronic music manifesto than that.

Mike also posted this video of Herbie on Sesame Street demonstrating the Fairlight for a group of kids that included Mohammed Ali’s daughter Tatiana.

Since these videos were made, the price of digital synths and sequencers has undergone the same extraordinarily rapid plunge as all other computer equipment. The first Fairlight model cost £20,000 in 1979. I have no idea what that is in dollars adjusted for inflation, but it’s definitely not cheap. You can have an identical setup on any laptop computer for a few hundred dollars today. What was the cutting edge of futuristic exotica in the early eighties has become ordinary.

The history of technology has this way of making the strange familiar. The tools advance much faster than our understanding of them, or our ability to make the best use of them. Will the funk prevail? It’s up to the musicians.

]]> http://www.ethanhein.com/wp/2009/synth-and-axe/feed/ 0 http://www.ethanhein.com/wp/2009/self-reference-in-computer-programming-and-hip-hop/ http://www.ethanhein.com/wp/2009/self-reference-in-computer-programming-and-hip-hop/#comments Sun, 31 May 2009 18:31:44 +0000 Ethan http://www.ethanhein.com/wp/?p=714 Like this sentence, computer programs and songs can refer to themselves. Many computer programs and songs are made of loops within loops within loops. Self-reference gives computers their extreme versatility. It also makes for richer, more interesting music.

Self-reference and looping in computer programs

When I was in fifth grade, we did some programming on Apple IIe computers using Sprite Logo, a student-friendly version of the venerable programming language Lisp. In Sprite Logo, you write commands that move a cartoon turtle around the screen (back in the eighties, it was more just an abstract triangle.) The turtle has a pen attached to its tail, and by specifying its path around the screen, you can make it draw shapes. By default, the turtle begins in the center of the screen, pointed up. Here’s how you tell the turtle to draw a box one hundred pixels on a side, in Logo-like pseudocode:

go forward 100 pixels
turn left 90 degrees
go forward 100 pixels
turn left 90 degrees
go forward 100 pixels
turn left 90 degrees
go forward 100 pixels
end

Here’s how you make the turtle draw an equilateral triangle:

go forward 100 pixels
turn right 120 degrees
go forward 100 pixels
turn right 120 degrees
go forward 100 pixels
end

You can tell Sprite Logo to repeat parts of the program by having it repeat parts of itself, using notation very similar to repeat markers in music. You might draw your square by defining a procedure to draw a single side, and then tell the program to repeat this procedure four times:

repeat 4 times: (go forward 100 pixels, turn left 90 degrees)
end

Here’s how you’d draw the triangle using repeats:

repeat 3 times: (go forward 100 pixels, turn right 120 degrees)
end

You could draw five triangles spaced two hundred pixels apart like so:

repeat 5 times: (repeat 3 times: (go forward 100 pixels, turn right 120 degrees)), go forward 200 pixels)
end

A more modern way to draw five triangles is to create procedures called “square side” and “triangle side,” and then have the program run them a certain number of times:

define 'triangle side' as (go forward 100 pixels, turn right 120 degrees)
define 'triangle' as (repeat 3 ('triangle side'))
repeat 5 ('triangle', go forward 200 pixels)
end

This kind of nested self-reference is so common in computer programming that it’s easy to forget how weird it is. Computer programs use the same code for both programs and the data that the programs are acting on. In other words, programs can use themselves as data. They can take their own code as input, and can output code too. You can nest layers of self-reference within self-reference in your programs to whatever depth you want. Such self-referential nesting is considered good programming technique, and most of the software we use every day is full of it.

Self-reference and looping in music

Music is full of self-referential loops. No form of music is more self-referential than hip-hop. In “My Melody” by Eric B and Rakim, Eric B takes the line “Check out my melody” and re-sequences its DNA, live on tape, using a sample of the song itself:

Ch-ch-ch-ch-check out, check out check out my melody.
Ch-ch-ch-ch-check out, check out check out my melody.

Digital audio supports effortless and endless recursion. You lose a little signal quality duing the encoding process, but once you have your list of ones and zeros, you can copy it flawlessly across any different medium, as many times as you you want. It’s not uncommon for DJs and producers to heavily sample themselves, or their own projects, and it’s not uncommon to use samples of samples of samples.

Any song that samples the ubiquitous “Funky Drummer” remix is already a remix of a remix. This is before we come to the uncountable thousands of samples of tracks based on samples of the remix, or samples of those tracks.

A particularly remarkable knot of self-reference is “The Score” by The Fugees, from their album of the same name.

“The Score” is based on samples of “My Melody,” “Dove” by Cymande and “Planet Rock” by Afrika Bambaataa, itself based on interlocking excerpts of other tracks. “The Score” also includes samples from every other song on the album “The Score”, and those songs mostly contain samples of still other songs:

Douglas Hofstadter thinks that self-reference is the key to consciousness. That could explain why it’s such a source of fascination for me: I’m seeing a reflection of myself.

The simplest sheet music reads as a straightforward top-to-bottom list of instructions. You start on measure one and read through to the end sequentially. That’s fine unless the music is very repetitive, which most popular music is. The loop is the basic compositional unit of nearly every song you could dance to. The problem is that writing loops out sequentially is very tedious.

Rather than writing the same passage over and over, you can save yourself a lot of laborious writing by using repeat markers. They’re like the GOTO instruction in BASIC. Here are the first four bars of “Chameleon” by Herbie Hancock. This four-bar phrase repeats hundreds of times over the course of the song. You wouldn’t want to write them all out. With repeat markers, you don’t have to.The repeat markers are the things on the ends that look like brackets with two little dots inside them. When you get to the closing repeat marker at the end of the passage, you jump to the opening repeat marker.

By default, repeat markers tell you to just play the repeated section once. You can also specify any number of multiple repeats. For “Chameleon”, that wouldn’t help much, because if you said repeat 128 or 256 times, no musicians could count that high. For open-ended music, you’re better off writing “repeat until cue.” This leaves it to the performer to decide how many repeats there should be.

Repeat markers give sheet music the topology of a clock face. Here’s how you hear the Chameleon loop. Read clockwise:

Western music notation also includes more complex repeats, with different conditional instructions waiting for you depending on whether it’s your first, second or third pass. Repeats get combined with special jump instructions like DC, short for Da Capo, “to the head.” DC tells the performer to jump to the beginning of the piece. Coda, “tail”, means “jump to the ending.”

Through clever use of repeat markers and jumps, you can fit elaborately complex musical scores onto a sheet or two of paper, which is very convenient if you’re playing an instrument that makes it hard to turn pages in mid-flight.

Even with its repeats and jumps, European classical music is mostly linear. The scores can be expanded into single rows of measures, like a chain of paper clips. Open-ended loops, the ones marked “repeat until cue”, are another story. A linear expansion of a piece containing open-ended loops will be different for every performance. Who knows how many paper clips you’ll wind up with in your chain?

European classical music can get boring because it isn’t repetitive enough. Outside of western Europe, open-ended repetition is the central organizational element of music. We in America have been wise to pay attention to this lesson. Jazz, country, rock, funk, hip-hop and dance music of all description use some form of “repeat until cue” in almost every song.

James Brown in particular was a master of open-ended loops. Usually bandleaders take the musicians in and out of loops through hand signals or eye contact. James Brown preferred to shout instructions to his band out loud in mid-song, and his shouts became a key element of his music. The most famous example is in “(Get Up I Feel Like Being A) Sex Machine.”

As the band loops on the main E thirteenth chord riff, James Brown and Bobby Byrd debate whether it’s time to take it to the bridge:

James Brown: Bobby! Should I take ‘em to the bridge?

Bobby Byrd: Go ahead!

James Brown: Take ‘em on to the bridge!

Bobby Byrd: Take ‘em to the bridge!

James Brown: Should I take ‘em to the bridge?

Bobby Byrd: Yeah!

James Brown: Take ‘em to the bridge?

Bobby Byrd: Go ahead!

James Brown: Hit me now!

The band transitions into a loop on A ninth. They play that loop until James Brown orders them back to the main part. At the end of the song comes another debate:

JB: Can we hit it like we did one more time, from the top? Can we hit like that one more time?

BB: One more time!

JB: One more time, let’s hit it and quit!

BB: Go ahead!

JB: Can we hit it and quit?

BB: Yeah!

JB: Can we hit it and quit?

BB: Yeah!

JB: Can we hit it and quit?

BB: Yeah!

JB: Hit it!

Loops are easy to memorize, but not so easy to perform. It takes deep concentration to play James Brown songs. Musicians trained in the Western classical tradition often find reading through a complex linear score to be easier than sustaining an open-ended groove.

Electronic instruments, on the other hand, make looping a breeze. Once you have a drum machine pattern, sample or MIDI sequence set up, you can loop it effortlessly and endlessly. The effort comes in breaking the symmetry, deciding how long the loop should play, when parts should enter or exit. My friend Josh Koppel likes to use the phrase “a digital thing in analog form.” In the hands of James Brown, his band functioned as an analog loop and sample player, one that could improvise to boot.

The computer science equivalent of “repeat until cue” is the for loop, also known as the if-then loop. Instead of explicitly telling the computer how many times to repeat a given instruction, you can have it keep repeating until some condition is met. Let’s say you want the computer to list every number from one to ten thousand. Here’s one way to do it in pseudocode — the second to last statements is the if-then loop.

Input starts at zero.

Input plus one equals output.

Print output to screen.

If output is less than ten thousand, then take output as the new input and repeat.

If output equals ten thousand, then end.

Using a few if-then loops, you can generate huge or even infinite amounts of complexity from very short programs. Fractals like the Mandelbrot set are generated using just a few simple loops.

Computers need to be told explicitly when and how to terminate their loops. Otherwise, they go around and around forever, a condition you experience as a crash. Humans are smarter in this regard: when told to repeat forever, we eventually get bored and stop.

When you grow up playing video games, like I did, the primitiveness of office software user interface design comes as a shock. The desktop metaphor was a brilliant stroke back in 1970 when they thought it up at Xerox PARC, but I feel like it has outlived its usefulness.

User interfaces are the first and most immediate form of computer instruction, and for many people the only instruction they ever receive. Not every interface designer teaches their own products equally well. The problems mostly emerge from designers’ presuming implicit knowledge from the user that might not really be there. There are plenty of computer science concepts that are common knowledge to programmers and engineers, but that are esoteric or totally opaque to the population at large. For example, the general public uses the terms memory and storage interchangeably, even though they refer to different computer components that function in very different ways. Most normal people don’t have mental models of a computer program’s inner workings, and rely entirely on the interface to provide the model.

The desktop metaphor treats the screen of a computer as if it’s the top of your desk. Great, except that it’s vertical instead of horizontal, and the laws of physics mostly don’t apply. A window in an operating system isn’t very much like a window in a wall and is even less like a sheet of paper. Typing some text on the screen only very superficially resembles typing it on paper. Unsaved text is in volatile memory that needs to be continuously powered to work. If you turn off the computer, intentionally or not, memory gets instantly blanked, and your text is gone forever. The only way to prevent this tragedy is to make sure to explicitly tell the computer to copy the text from memory onto a storage device like the hard disk.

Computer experts sneer at people who don’t understand the concept of saving, but it’s wrong to sneer, because there’s no reason for someone to intuit the difference between volatile memory and non-volatile storage unless they’ve had it carefully explained to them. We’re used to making marks on a surface and having them persist unless we take steps to erase them. There is a trend towards auto-saving in software, but it’s been absurdly slow in coming.

The filing cabinet analogy for hard drives made more sense back in the eighties, when disks were expensive and limited in their storage capacity. The first computer I was in charge of was the one I took to college in 1993. I knew intimately which programs I had installed on it at all times, because if I wanted to install a new one, I had to erase something first. Now the hard disk’s filing system has to contend with billions of bytes of data. In this era, a big searchable database is a better model than a filing cabinet. Instead of putting a file in a single, unambiguous location, you’re better off tagging it with descriptive metadata so you’ll be able to find it in a search later. The filing cabinet analogy has the virtue of accurately representing the file system’s actual organization, but it’s not very human-friendly. Our own minds are organized into associative networks, not hierarchical directories.

The most annoying aspect of the conventional desktop metaphor is its Escher-like recursiveness. Within the screen representing part of the computer is an icon representing the entire computer. The desktop folder appears to be inside itself. The recursion is interesting from a metaphysical perspective, but deeply confusing if you’re just trying to understand your file system.

Much as I love the Mac OS, its recursiveness can be even more confusing than Windows. The Mac has two sets of folders called Applications, Documents, Library, and so on. Even though their names are identical, their identities and functions are totally separate.

For non-expert users, probably the most difficult aspect of the graphical user interface is keeping track of the keyboard focus. Even the Mac OS doesn’t always do a wonderful job of making it obvious which text field in which window has the keyboard focus. In the screenshot below, the text cursor could be subtly blinking in any of at least three different places.

As a teacher of novice users, the phrase you hear a lot is: “I don’t know where I am, I want to go here.” This is an interesting phrase to me. No one says, “I don’t know which task or process is set to receive text input.” People intuitively conceptualize computer interfaces as places inhabited by their own bodies. This intuition is misguided – even when you “surf” the web, you’re not going anywhere, bits are being transmitted to and fro from one computer disk to another. But there’s no talking people out of their intuition. Computer programs are easier and more fun to use when they present a user illusion that accommodates our instincts.

Windows represents your onscreen avatar as a little arrow, a little cartoon glove or a little hourglass. Macs represent you as an arrow or a psychedelic rotating rainbow ball. Efforts to make the computer into a “person” you’re talking to always fail. Everyone hates Microsoft’s anthropomorphic paper clip and dog, and people would rather interact with impersonal Google than to ask Jeeves. It would be better to represent the operating system as a place, with the user “embodied” by an avatar. It doesn’t have to be a person, or even humanoid. It can be a bird or a robot or whatever. But you do have to be able to easily control and manipulate it, and it needs to unambiguously represent the keyboard focus.

I think the future of interface design is to be found not in Apple’s products, but in video games, especially eighties video games, most especially the ones by Nintendo. The user interface of every Nintendo product has to be intelligible by semi-literate young children in every world culture. For the most part, they succeed heroically. Long before video games had any of their present lavish production values, they conveyed a strong sense of first-person experience that could be instantly grasped by preschool-aged children. This metaphor is as old as human consciousness, and we’re vastly more adept with it than we are with the metaphors of desktops, file cabinets and disembodied cartoon fingers. If I controlled the universe, I’d want my computer’s file system to look like this:

The Mario games are models of clarity and graphic economy. One visual metaphor I’m particularly fond of is the level selection system in Super Mario 64 — I’d include a screenshot but I can’t find a good one. You start the game in Princess Peach’s castle. Each level is represented by a painting hanging on the wall. To visit that level, you jump into the painting. I’m imagining a nice system for pointers and aliases where you could take the paintings off the wall, carry them around with you as you see fit, rearrange them, etc.

Mario 64 is a 3D game, but I’m not advocating the use of 3D spaces as interfaces generally. I think eighties video games are a better model for interface designers exactly because they’re limited to 2D spaces with limited attempts at depth. Unless it’s handled very expertly, illusory projections of 3D spaces onto a 2D screen cause a lot of confusion. Playing a game like Halo or Quake is a poor approximation of our actual 3D experience, it’s like viewing the world through a cardboard box with a little rectangular hole cut through it, and with only one eye. I think it’s better to look for creatively optimized plane layouts than to burden the user with a lot of projective geometry.

You can’t ask the computer. Computers fail when you ask them questions with no unambiguous answer. Dividing by zero is just such a question. Folklore suggests that asking the computer to divide by zero makes it spectacularly explode or something. In reality, it returns an error message or the reply Not A Number, or it gives a wrong answer, or the program terminates, or sometimes the machine falls into an infinite loop.

The internet’s favorite divide-by-zero error is the one that temporarily crippled the USS Yorktown, a Ticonderoga-class cruiser that was the test bed for the Navy’s Smart Ship program. When a crew member typed zero into a database field, the computer tried to divide by it, crashing the system badly enough to cripple the ship’s navigation systems for several hours.

Humans are smarter than computers in some ways, and we’re capable of coming up with creative answers to seemingly unanswerable questions. So what do you get when you divide something by zero? My answer draws heavily on the entertaining wikipedia article. For the sake of simplicity, let’s say we’re dividing one by zero. The math people have a crafty method for dealing with problems you can’t approach directly. You can edge closer and closer to the problem and see if you converge on an answer. So instead of dividing one by zero, you could try dividing it by smaller and smaller numbers that approach zero. One divided by one tenth is ten. One divided by one one-hundredth is a hundred. One divided by one one-thousandth is a thousand. Since one divided by one one-gazillionth is one gazillion, logic suggests that one divided by zero is going to be infinity.

It makes sense, but there’s a problem. We’ve been approaching zero from above, but we could just as easily approach it from below. When you divide one by negative one tenth, you get negative ten. One divided by negative one one-hundredth is negative one hundred. One divided by negative one gazillionth is negative one gazillion. So you could just as easily say that one divided by zero is negative infinity. Both infinity and negative infinity are equally valid answers. Here it is as a graph.

Some people interpret this graph to say that infinity and negative infinity are the same number. It’s not as crazy as it sounds. Let’s say that instead of being on the computer screen, the graph was drawn on a globe. Imagine the number line wrapped around the equator. Say the spot where the Prime Meridian crosses the equator is zero. If you’re in a rowboat bobbing in that spot in the Atlantic Ocean, enjoying the warm breeze, you can think of the positive numbers as going off along the equator to the east, and the negative numbers going off to the west. Infinity is the farthest possible point away from you on the equator to the east, and negative infinity is the farthest point away from you to the west. On the Earth, positive and negative infinity are the same place, the International Date Line in the Pacific. For this image to be totally accurate, the Earth would have to be infinitely large, but the math guys bracket that. By this thinking, one divided by zero does have a single, unambiguous answer: this mysterious number called unsigned infinity.

When you type “divide by zero” into Google images, you get a lot of stuff like this:

Our European-descended philosophical assumptions are at work here. Western thinkers prefer clear, unambiguous, yes-no dichotomies. Paradoxical and multiply-determined truths make us anxious. Some of the internet cartoons show dividing by zero ripping holes in the space-time continuum, forming black holes, or making your head explode. That much hyperbole has to conceal some pretty intense anxiety. I know these pictures are jokes, but I agree with Freud, on some level there are no jokes.