Thursday, October 29, 2009

Electric guitar amps for dummies

I have fully immersed myself in the world of electric guitar for long enough that I forget that not everyone wets themselves over the thought of an all-original 1965 Blackface fender Twin. This, then, is for my friends who have no idea what I'm talking about. Also, I'm not an electrical engineer or physicist, so my descriptions of the circuits involved are going to be accurate enough but probably very very wrong. Please forgive me.

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Your standard-issue acoustic guitar works because the strings vibrate at a certain frequency, and those vibrations are transferred to the hollow body of the guitar. The sound waves bounce around in there and get the whole body vibrating. Since a big piece of wood vibrating at 440 Hz (or whatever) will make more noise than a thin piece of wire doing the same, the guitar is naturally amplified, and the sound is loud enough to fill a small room.

This is great for playing alone, but what if you need to be heard in a concert hall over, say, a drummer, bass player, and horn section? You could theoretically build a HUGE guitar, but that would be impractical. Instead, what some genius in the 1930s realized is that you could use electricity and magnets to amplify the sound. The important parts of an electric guitar, then, are the neck, the strings, and a few electromagnets underneath the strings called the "pickups." Nothing else is vital--not the shape of the body, not the paint, nothing. That's why you can have electric guitars that look like this but most acoustic guitars look something like this

The pickups are the little rectangle or oval shaped things underneath the strings you'll see on any electric guitar. As stated earlier, they're usually not much more (or at least don't have to be) than a magnet wrapped in wire. When a guitar string (made out of a magnetic metal) vibrates at a certain frequency, it disturbs the magnetic field, creating an electrical current at that frequency. This current travels down the wire from the guitar and heads into the amplifier, where the signal is amplified (the waves are just made bigger) and this current then causes the speaker of the amplifier to vibrate at exactly the same frequency as the string(s) were.

Simple, right? Yes, in principle. But then it gets complicated.

To start out with, there are two basic types of devices you can put in an amplifier to actually do the grunt work of making the signal stronger. In the olden days, they used vacuum tubes. Then, in the 60s and 70s, somebody discovered that you can use transistors to do the same thing. As you might be able to tell from the picture, the transistors have the advantage of being a hell of a lot smaller. Solid state amps (as ones based on transistors are called) are also cheaper to make and have less chance of distorting the signal. Perfect, right? Technology is on the march and tomorrow is brighter than today!

Except no. Most amplifiers for things like microphones and audio systems try to reproduce the signal exactly as it came in. Early guitar amps did this as well, until somebody figured out they sounded damn cool if they got turned up really loud. What was happening was that the level of the electrical signal was too high for the electronic components in the amp, so the top part of the wave got "clipped."

Visual aid:

In most audio amplification, this is VERY BAD, because it sounds like crap. For a fun experiment, turn your computer speakers up all the way and play a song. It will probably sound a bit like diarrhea. For whatever reason, however, when you do this to a guitar, it sounds a bit like this. There are, of course, levels of distortion. In the clip above the amp is pushed into a moderate level. If you listen to someone like B.B. King, he has the amp set so that it's just a smidgen over its maximum, and you end up with a very smooth, mild, almost unnoticeable distortion. If you listen to a heavy metal band, however, they've got the things turned up so high that the waves end up looking square.

Why exactly most people enjoy the sound of an "overdriven" or "distorted" guitar (the two terms mean roughly the same thing) is hard to answer. Certainly many people who grew up in an era in which the sound was to be as avoided in guitar amps as it would be in any amplifier say that it sounds like "noise" to them. For whatever reason, though, most people who have grown up listening to music since the 60s enjoy it and find it sounds "gritty."

So what does this all have to do with the tube vs. solid state issue? It turns out that a tube amp (also called a valve amp in England, for some reason) sounds better overall, but ESPECIALLY when it is distorting. This is because generally tube amps will have a much more graded scale, from creamy smooth blues sounds at around 3/4 on the volume dial to pure, balls-to-the-wall rock if you turn it up all the way. The transistors in solid state amps tend to handle the signal differently, by keeping it as clean and undistorted for as long as possible before suddenly breaking into very harsh, unpleasant-sounding distortion. There are also other factors, such as the supposed "warm" sound of a tube amp versus the "lifeless" sound of a solid state, which do have some validity--but to the majority of untrained listeners they're pretty damn similar. Even virgin ears, however, can usually tell the difference between "cranked" (guitar talk for turning it up to the point of distortion) tube and solid state amps.

Because they sound better, they're more delicate, and vacuum tubes aren't used in much else nowadays, tube amps tend to be more expensive. A smallish (usually around 15 watts or so) solid state amp will tend to run about $100-$200 dollars. A tube amp of a similar size will cost you minimum $300-400, and sometimes up into the thousands. For this reason, most beginner-level amps are solid state, and the vast majority of pro guitarists (and, indeed, almost anyone who is playing actual shows for a paying audience) bite the bullet and upgrade to a tube amp at some point. Occasionally guitarists (often jazz guitarists) will play with high-end solid state amps if they want a very clean sound, and some pretty big-name guitarists have heavily used solid-state amps in the studio (Brian May!)--but in the vast majority of times tube amps are the way to go.

So now you know the basics about guitar amps. We've only scratched the surface...

It's been a while

Sorry folks, been busy with school and life and a bit too lazy to keep this up.

I'm writing this as I lie in bed with what is either a very nasty cold or the beginnings of the flu (swine or otherwise). Luckily I have the internet, some class readings, a few books, and some video games to keep my company while I try to not feel all achy and coughy.

I'm kept in high spirits, however, by the fact that I have a new toy:



A Traynor YGM-3 guitar amp (from 1971!).

All tube, 22 watts, built in reverb and tremolo...nice stuff. It'll be my new go-to amp for Sugar stuff. To explain what the hell that all means, maybe you should check out my next post...

Saturday, October 17, 2009

Facebook's targeted ad fail (cont.)

-"Pick your pleasure! Diamond rings from Versace, Gucci, Baby Phat, and more!"

-"All sweaters and outerwear 25% off from Pennington's size 14+ woman's clothing"

and this one wins for pure irony:

-"Get your online BS in marketing!"

Friday, October 16, 2009

On navigation and Walruses

True to the name of the blog, I thought I'd trumpet a little bit about the small modicum of fame I have achieved as of the publication of the last Walrus, a widely read Canadian magazine somewhat akin to the New Yorker in content and tone, although rather differing in the comprehensibility of name choice.

The last issue contained a feature article on whether or not modern technology is killing our ability to navigate our way around the world (cleverly called "Global Impositioning Systems") which features quite prominently Dr. Veronique Bohbot's lab, where I have worked since May. Cool beans.

Also, there's an accompanying video. Watch the whole thing--it goes to our lab at about 1:30, and you can even hear and see (I'm wearing 3d glasses, the height of chic) helping the author around the lab in the middle of it! It also feature Dr. Bohbot herself and some of my lovely co-workers. Check it out!

In totally unrelated news, I still am confused as to my own tendency to want to spell accompany with a "g" after the second "a." You'd think I would have learned by now.

Monday, October 12, 2009

Facebook's targeted ad fail

I'm convinced Mark Zuckerburg is somewhat of an evil genius. Although the concept of Facebook is nothing really that innovative, what he (or someone he was working with) realized was that what social networks end up giving you--laid out in front of you like a Thanksgiving day table--is the personal information and tastes of a huge swath of the 15-30-year-old population. We've probably all heard of the scandals over our information being sold to advertising partners, and we've all probably shrugged off the cries of the privacy advocates who recognize that we're all participating in what amounts to a giant marketing survey.

So, given that Facebook pretty much exists to mine our personal pages for information to sell us shit, why is it that the targeted ads on the side are always (to use internet lingo) so full of fail?

-"Meet hot single Canadian girls now!" and the like. One would think it would be the most efficient use of ad space for facebook not to show these to people who are listed as being in a relationship? Also, Canadian girls don't usually go for internet dating. The traditional ones won't come out to dinner with you unless you bring them a pair of moose antlers and three beaver pelts.

-"Find the best place to celebrate Diwali near you!" I'm not Indian, although I do greatly enjoy butter chicken.

-"The BEST DNA decontaminator!" Urgh. Really?

-"A Conversation with George W. Bush in Montreal on October 22nd! Tickets still remaining, get yours fast!" Oh boy, my favorite president in my home city?! I'll have to bring an extra pair of shoes.

-"Download the free online beer fridge!" This isn't as much mistargeted as just mind-numbingly stupid. After a hard day, there's obviously nothing I love quite as much as an ice cold binary beer.

-"Etes-Vous Francophone? Travaillez pour Facebook!" Yes, I'm a francophone. That's why I'm from California and my facebook page is in English.

-"Too early for Christmas?" Yes, actually. Why on earth would they have these ads up now? "I didn't think so. Download an entire album of Christmas piano for $3.96!" ...oy. when I do my christmas music shopping, I only go for the highest quality merchandise. This four-dollar crap just won't cut it.

-"Play Evony Now: World's #1 Web Game! Play subtly with me now! FREE forever!" Hmmm...

-"Become a fan of the Jonas Brothers!"

Wednesday, October 7, 2009

Now you can stalk me MUCH better

Apparently Google maps now has street view for Canada. This means that anyone who has never come to visit me in Montreal can now come visit me in internet-land and not feel guilty about having never come to visit me.

I'm kidding on that last point.


Here's my cross-streets (I'm not posting my exact address on the internet, geez). Ta-da!

Tuesday, October 6, 2009

Playing around with photos...

I thought this one turned out rather nice...didn't do much to it, either: just contrast, focus, and very very slight color adjustment.

 
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(you can click to make it bigger)