What I Learned Today

An A note is a vibration at 440 Hz — but it wasn’t always so. Prior to 1939, musical conventions varied by location, which must have caused some interesting results if musicians from different areas tried to play together (the A note is commonly used for tuning, the set point from which all other notes are created). In 1939, an international treaty was signed fixing A on 440 Hz, not only to enable musicians to play together, but to standardize the creation of musical instruments. A clarinet creates notes based on its length, so its physical construction is influenced by the standard frequency chosen for A.

This standard, the basis of music tuning, is an example of a convenient yet arbitrary choice for a constant reference value. Some values we use commonly are dictated by physics: in free fall towards the Earth, objects accelerate at 9.8 m/s^2; the location of 0 latitude is the equator. But others, like the location of 0 longitude, are more like the A note. While the equator is defined by the spin axis of the planet, there’s no physical reason to prefer one location over another to serve as the reference point for longitude calculations. It is, however, awfully convenient for us all to agree on the same location!

Our temperature scales fall somewhere in between. The establishment of 0 or 100 degrees is arbitrary, but an effort was made to associate them with physical phenomena, like ice freezing or water boiling. The length of the meter (also arbitrary) was originally set to be “one ten-millionth of the distance from the Earth’s equator to the North Pole (at sea level)” in an attempt to tie it to a physical property, but since 1983 it has been instead defined as the distance light travels in a vacuum in 1/299,792,458 of a second (!). But that’s really just convenience too, since light travels at 299,792,458 m/s… too bad we didn’t just decide that light travels at 300,000,000 m/s and get the length of the meter from there! I imagine that any such change would be a nightmare to implement, though.

These values influence our everyday life: how much gas in a gallon? How much flour in a cup? How many atoms in a mole? It can be useful therefore to know which ones were derived from physical constraints and which ones were obtained from consensus!

I finally got sick of the cassette adapter I was using so that I could listen to my iPod Shuffle in my car and decided to upgrade my car stereo. It turns out that you can get a new base model for $60-70, which was much cheaper than I’d thought! (It really doesn’t take much to leapfrog the technology used in my car’s original 1999 stereo.) Then it’s just down to the investment of your own time to get it installed. (Given Evan’s offer to show me how it’s done, there was no way I was going to pay an installer to have all that fun!)

There were several new features that I wanted: a front AUX input, so I could plug my Shuffle in directly; a display that showed the title of the song currently playing from the radio; and a CD player. At Best Buy, the front AUX port and the CD drive were easy to spot on any stereo, but I couldn’t tell which ones would show song names. I asked the salesperson, who replied, “All of them.”

I picked out the base Pioneer model (1300MP), and a few days later we got together to install it. Evan figured out via google the easiest way to open up my console, and after detaching the wiring plugs for the hazard and rear defrost buttons, we had the stereo out:

We opened the new stereo and commenced to connect its wires to a “wiring harness” that has plugs to fit the sockets provided by my 1999 Nissan Sentra. This meant stripping the ends of 11 wires and then soldering them to their corresponding wires in the harness. I experimented with my “less hazardous” lead-free silver solder, but ended up switching to Evan’s “wash hands before eating or smoking” lead solder, which works tons better. Prior to soldering, Evan threaded bits of heat-shrink tubes onto each wire, and after they were connected, we slid the heat-shrink up over the join and melted it with a device like a super-super-charged hair dryer. The tubes shrank to a neat fit onto the wires, yielding tidy connections that wouldn’t short against each other (stereo out of view on the left, wiring harness on the right):

We then wrapped electrical tape in spirals along the length of the wires to package them up prior to putting the stereo back into the car.

And with that, it was in! It took us about an hour and 15 minutes from start to finish.

I enjoyed the stereo for about 10 minutes until I realized that while the CD player and the AUX port worked fine, it didn’t display anything about the current song playing from the tuner. Arrrrgh! I pored through the manual and found no mention of this feature at all. So I went back to Best Buy where the installer tech informed me that this feature is called Radio Data System and that I needed to find a stereo with “RDS” listed as a feature. He assured me however that Best Buy would take the stereo back since I’d bought it thinking it had a feature it didn’t, even though I’d already installed it.

On Amazon, I found a base-model Sony car stereo (350MP) that does have RDS, and is slightly nicer all around than the Pioneer, for only $10 more. When that one arrived in the mail, I sat down, this time solo, to undo and redo the installation process. Getting the heat-shrink tubes off the wiring harness was a pain:

After a few of these I figured out that I could instead score the tube in the middle and twist/slide it away from the join, then desolder the connection and pull both tubes off. Then even that got tedious, so I started just cutting the wires and stripping them back a bit more to expose fresh surfaces on the wiring harness end. I put on new heat-shrink tubes, then soldered the new stereo to the harness wires and used my multimeter to check that all of the connections were good. I shrank the heat tubes, wrapped the connection in electrical tape, and put the stereo into the car. Interestingly, it wouldn’t power on until I also plugged in the antenna cable — leading me at first to suspect a flaw in my work. But no! All was good with everything connected.

It was at about this point that I realized I’d left a CD in the stereo I’d just taken out of the car. At that point I was two hours in and not willing to remove the new Sony stereo, unsolder its connections, reconnect the Pioneer, eject the CD, undo its connections, and reconnect the Sony. So I called it a day and savored the Sony’s futuristic blue glow, dancing equalizer dots, advanced display, and Radio Data System.

Old stereo… new stereo!

Epilogue:

• To avoid the hassle of soldering, apparently it is possible to use wire nuts (though they may not last as long) or a kind of wire-crimping device that is what Best Buy installers would use.
• When I took the Pioneer stereo back to Best Buy, they sadly were not willing to take the time to get my CD out of it (e.g., pull out the Pioneer display stereo, plug the one I had in, and eject the CD). So I ended up returning it with the CD inside. At that point, any route to recover the CD would cost far more (in money and/or time) than simply replacing it. I did try hooking up the yellow (+) and black (-) wires to a 12V power supply, but that had no effect, and I didn’t want to experiment further and kill the stereo in the process.

My friend Jon Stokes recently posted a delightful mapping from chess moves to music, including several compositions based on famous chess games. This is exactly the kind of geekery that I find most enjoyable, a quest that seeks both interesting new patterns and interesting new ways to experience what we already know. I also learned the word polyrhythm, which occurs when two different rhythms are played against each other. This is frequently found in African music, but apparently occurs even in music by the Beatles (e.g., “Happiness is a Warm Gun”).

He then followed this post by mapping the Fibonacci sequence to music, yielding a lovely fugue and some interesting analysis. I hadn’t known that the Fibonacci sequence modulo 7 produces a repeating sequence — and handily (for 4/4 music), one of length 16! More fun fodder for the future, should I ever be teaching recursion again. I’m charmed by this process of converting an abstraction into the auditory equivalent of a visualization (auditorialization?).

Nice work, Jon!

Today I got my first taste of “nerdcore hip-hop” (thanks Jon!). This stuff is absolutely fantastic… and I’m not normally a hip-hop fan! I’m a sucker for clever lyrics, I guess. :) Here are some of my initial favorites, which you might also enjoy:

• “Kill -9” (lyrics: see the title of this post) and
  “So Much Drama in the Ph.D.” (lyrics)
  by Monzy (CS grad student at Stanford)

• “ASCII Antics” (alphabetized lyrics)
  by MC Plus+ (CS grad student at Purdue)

• “It Is Pitch Dark” (lyrics: yep, “you are likely to be eaten by a…”) and
  “This Old Man” (lyrics)
  by MC Frontalot (not a grad student)

I got a 2 GB iPod Shuffle for my birthday (thanks, Mom!) — an entirely unanticipated gift. I’d never owned an MP3 player and, when I’d seen the Shuffle in stores, figured it wouldn’t really be all that useful — no display, you know? But then I got one of my own, and my world changed.

My favorite music is with me everywhere I go! This has literally transformed my commute (via tape adapter), my walks, and even washing the dishes (while I can play the same music through my laptop’s speakers, it sounds so much better through headphones). For walks, it’s almost as good as ThinkGeek’s personal soundtrack t-shirt, except that it doesn’t annoy others around me. (I do have to check my impulse to sing along, though!)

I thought the lack of a display would bug me. But it turns out that it supports the main ways I listen to music anyway — sequential, or random. If I don’t like the current song, I can just skip to the next one. What a beautiful little device!

Even better: I’ve discovered an actual use for podcasts! I’d experimented with a couple in the past, but whenever I’m actually using my computer, I’m almost always processing information (writing code, reading papers, work stuff) in a way that doesn’t permit me to pay attention to talk. But now… I can listen to podcasts in all of those same places (car, walks, dishes)! My favorites so far are:

• The Loh Life, by Sandra Tsing-Loh: I love her articles in the Atlantic Monthly and, the few times I’ve caught her in the mornings on KPCC, I’ve loved her short (~3-minute) monologues. But it never seems to sync up with my commute these days. No more! Now I have Sandra with me anytime I want! Edit: Sandra also has a daily 1-minute show called The Loh Down on Science!
• Cast On, by Brenda Dayne: I experimented with a few knitting podcats, but this is the only one that really stuck. I think I’d listen to “Cast On” even if I weren’t a knitter, just for the fabulous music she plays throughout the show. I haven’t recognized a single song, yet I’ve liked every one of them! The knitting-related material is great, too, from her “sweater of the day” stories to the thought-inspiring Essay.

Podcasts, like audio books, are definitely great for knitting accompaniment. Now my Shuffle makes it easy and portable. Can Apple ever go wrong?