Thursday, February 18, 2010

Music Production for Dummies (How to make a million clams in one easy lesson.) – Lesson Two

The musical landscape (or portrait if you turn it sideways)
I spoke in the last lesson about pallets and painting. That is the vision I have of music production. You are an artist and you have tools. You have a pallet filled with colors and a can full of brushes. As producer, you select the color and brush and layer on the sound. Painting is two dimensional (unless you paint houses), but music production is multidimensional.

I image my musical canvas (keeping the metaphors unmixed!) as a coordinate system. You remember from High School math the Cartesian Coordinate System, don’t you? That was the cross on the paper with the ‘X’ axis going horizontal from left to right and the ‘Y’ axis going vertical from bottom to top. You can add a third dimension, ‘Z’. Now imaging more than three dimensions. Sort of hurts the brain, doesn’t it?

The musical dimensions
In modern music production there are literally several dimensions. Good old stereo, where the music comes out of two speakers across from each of your ears, is a simple example. I adjust different instrument and vocal tracks onto the left and right speakers using the “pan” control. But I imagine that the stage not only has width, left and right, but also depth, forward and back. One way I adjust depth is with the gain control which affects the volume or loudness. Imagine soft sounds are farther away.

I also work with a vertical dimension. That is the tone or frequency (pitch) range. Bass is on the bottom and treble is on the top.

There are several other parameters or “things” I can adjust with my post-production equipment and software, including echo and reverb as well as effects like chorus and flanger. These can affect what I call “presence” or nearness of the sound. We’ll get into those in a future lesson.

Modern musical reproduction
Let’s take an asside for a moment and discuss modern day music systems and “stereo.” Things are a lot more complicated these days. Music can be encoded to come out of more than just two speakers. To begin with, there is the “subwoofer.” This is a single, large speaker that is equalized (think filtered) to only play the lowest frequencies. Actually there are two kinds, subwoofer and “extreme” subwoofer called LFE for Low Frequency Effects. The latter is used with movies to provide the tones almost below the range of human hearing. These sounds create the impression of great power. Modern day sound systems are often used with DVDs both to show video or movies and also to encode more tracks than regular stereo “red book” CDs. (Red book is the name of the common CD standard.) I love to play the beginning of the “Lord of the Rings” to people on my home theater which has a LFE (60 watt, 15 inch speaker). When the bad guy gets his ring finger chopped off and there is some sort of slow explosion, I can rattle the furniture and a few teeth. You don’t “hear” it as much as “feel” it. My father-in-law ran from the room when I did that. I asked Linda, “Did I have that too loud?”

Systems that decode multiple channels of audio have been the work of a company called Dolby for many years. They were first known for musical “noise” reduction, but they have pioneered a lot more as music reproduction has exploded into three dimensions. Following the standard set by Dolby, a 2.1 system (or Dolby 2.1) is a stereo system with two speakers (2), left and right, and with one subwoofer (.1).

Digression into frequency and wavelength
I will digress further and explain why only one subwoofer is required. All individual sounds have a frequency. The lowest frequencies or sounds we can hear are below 100 cycles per second or Hertz. The range of a subwoofer is 20 to 100 or 200 Hz. The highest frequencies we can hear depends on our age, but it is around 10,000 Hz in a young person. We do need frequencies higher than that to fully appreciate something called a transient or rapid rise which means that good “hi-fi” systems reproduce sounds to about 20,000 Hz or 20 KHz. Above that, only the dogs can enjoy.

You can measure frequency in cycles per second or in something called wavelength. That is the length of a sound pressure wave. This depends on the speed of sound and other parameters, and I won’t get technical except to say that wavelength is the reciprical of frequency. That means as frequency goes up, wave length decreases. If you double the frequency, the wavelength is half. The wavelength of a 1 KHz sound is a little over a foot and a 20 KHz sound is about half an inch. The human brain determines sound location by comparing the sound in the left ear to the sound in the right ear and distinguishing tiny timing differences. (What a clever creator we have!). But when wavelength becomes too long, the sound in the two ears can’t be differentiated. Since 100 Hz wavelength is over 11 feet long, the sound arriving at the two ears (only separated by about 6 inches) is almost identical. For that reason, we can’t distinguish low frequencies, those below 200 Hz or so, and tell where they came from. We can hear them fine, we just don’t know where in the room they came from.

Combine that scientific fact with the fact that the amplifier and sound system required to reproduce low frequencies or bass tones requires a large speaker surface and a lot of power, the engineers decided to create one powerful amplifier with a large loudspeaker and filter the low frequencies from both the left and right stereo channels and combine them into one speaker: the subwoofer.

Return to modern music reproduction
So Dolby 2.1 is the new version of “stereo.” Sound systems take a normal stereo signal in two channels and produce the subwoofer signal. There are typically two smaller speakers or towers designed to handle the mid-range and high frequency sound in the left and right channel, plus a subwoofer which reproduces the bass sounds from both channels. You can put the subwoofer speaker where ever you like, with some out of the way location on the floor very popular. The left and right speakers should be placed some distance apart, best at ear level, and on the left and right of the listener. No special mixing or sound production is required to support Dolby 2.1.

In the last few decades, the movie industry (Hollywood) developed sophisticated sound systems for movie theaters to make them competative with watching TV at home. These systems wrapped speakers all around the theater in a form of “surround sound.” Again, Dolby was at the forefront of this effort as were people like Steven Spielberg and his company Digital Theater Systems. As technology marched on we started to get home theaters with DVD technology and surround sound came to the home. A simple one is 4.1 That has two speakers in the front, the normal stereo placement, plus the subwoofer (.1). What was added was a pair of “rear” speakers which were placed behind the listener and viewer. In addition, the stereo speakers were moved farther apart to create separation. That left something of a sonic hole in the middle, so Dolby 5.1 was invented. It added a center speaker. In theory you could just add a little of the left and right to produce the center sound: L + R, but that decreases the stereo separation, and the point of moving the speakers apart int he first place was to increase separation. So special mixing techniques were used to create the center channel and make it more than just L + R. Since this seems like the more speakers, the better, let’s add two more speakers on the same plane as the listener. These are called side speakers and this configuration is called Dolby 7.1. As you may have guessed, there is even 9.1, but 7.1 is pretty much the limit in home theaters. The many channels are called L, R, C, Sub, SR, SL, and RR, and RL. (Sometimes the rear is only a single speaker, RC. We still call that 7.1, but it is more 6.1!)

People like George Lucas (through THX, named after one of his early sci-fi movies) and Dolby have led the development of systems to encode DVD movies just like in the theater where there may be as many as 12 different pairs of side speakers each with a unique channel which lets the sound and music actually move around the theater. Modern home theater amplifiers can process the complex DVD sound and produce effects mimicing the theater. THX systems were designed to map the many, many speakers supported in the movie sound track into the simpler 5.1 or 7.1 in the home theater.

But we are here to talk about music, not movies. Of course, more music is being published on DVD these days which allows these multi channel, 7.1 encoding. Modern sound production software such as Digidesign ProTools and Adobe Audition allow a producer to mix in multi-dimensions. So 5.1 and 7.1 is available to the music producer if the final output will be put onto a music DVD (or in a movie).

I’m old fashioned
But I’m an old fashioned guy, and I stick to 2.1, which is really the same as simple stereo since the subwoofer does not have a discrete audio channel, it just combines the low frequencies of L + R using a filter. I don’t have 5.1 or 7.1 speaker system in my studio, and won’t be adding that any time soon, if ever.

So I stick to just panning from L to R. That is the KISS principle (Keep it Simple and Straighforward — or Keep It Simple, Stupid). I create the other dimensions using tone and pressence and several other tricks. As for these other tricks, you will have to wait for the next lesson, lesson three of my “Music Production for Dummies (How to make a million clams in one easy lesson.)”


Music Production for Dummies (How to make a million clams in one easy lesson.)

I love working as a producer. The collaborative and creative work just makes my juices flow. And when it comes together, no number of high fives can complete the celebration.

There are so many brushes in a producer’s pallet (warning — mixed metaphor alert), including tone, effects, stereo image, volume, and a few more that are not at all obvious. Let’s take a popular new song and map out how it was produced in one of my favorite motifs. I’ll say more about where this motif comes from later.

The song is “I and Love and You” by the Avett Brothers. These two have worked in blue grass and punk, but this song is a beautiful ballad format. (What’s with these punk bands and ballads? Sort of like Green Day with “Time of Your Life.”)

This latest Avett Brothers album was produced by Rick Rubin, and frankly you can’t really tell what creative parts and arrangement came from the Avetts and what part is from Rick (or even their bass player, Bob Crawford).

Rick is well known in the metal and punk arena starting with his production of the Beastie Boys. He has also produced Danzig, Slayer, Linkin Park, the Red Hot Chili Peppers, Metallica, and System of a Down. On top of that he has coproduced with Johnny Cash. Quite a resume I would say.

So, let’s get to the song called “I and Love and You.” I will map the song’s arrangement. It’s a simple little thing in D. This will work best if you play the music along as you read the words and production description. Ready? Here we go.

[It starts with a simple piano line D to G]

[Then Scott starts singing]

Load the car and write the note
Grab your bag and grab your coat
Tell the ones that need to know

[Now Seth joins in for a simple harmony]

We are headed north

[Back to simple voice and piano]

One foot in and one foot back
But it don't pay, to live like that
So I cut the ties and I jumped the tracks

[Again Seth joins in harmony]

For never to return

[Bring in the bass guitar with the piano]

[Add Seth’s harmony on the whole chorus]

Ah Brooklyn Brooklyn take me in
Are you aware the shape I'm in
My hands they shake my head it spins
Ah Brooklyn Brooklyn take me in

[A nice little piano turn-around into the next verse]

[Add strings]

When at first I learned to speak
I used all my words to fight
With him and her and you and me
Ah but it's just a waste of time
Yeah it's such a waste of time

[Join some subtle drums — the kick and the bass guitar almost meld]

That woman she’s got eyes that shine
Like a pair of stolen polished dimes
She asked to dance I said it's fine


I'll see you in the morning time

[Bring up the drums — let’s hear the snare and cymbals]

Ah Brooklyn Brooklyn take me in
Are you aware the shape I’m in
My hands they shake my head it spins
Ah Brooklyn Brooklyn take me in

[Time for a little Hammond organ sound (with Leslie) — getting phat]

[A little instrumental break]

[Now back to just the vocal and piano with the gentle harmony on the last line]

Three words that became hard to say
I and love and you

[Now the harmony becomes constant]

What you were then, I am today

Look at the things I do

[Bring back the bass, drums, strings, and organ]

Ah Brooklyn Brooklyn take me in
Are you aware the shape I'm in
My hands they shake my head it spins
Ah Brooklyn Brooklyn take me in

[Reprise the chorus and how let’s turn Seth loose with rhythmic counterpoint]

[Soft and simple now. Some strings and a little high register organ]

Dumbed down and numbed by time and age
Your dreams to catch the world, the cage
The highway sets the traveler's stage
All exits look the same

[End like the start — slow it down — fade it out]

Three words that became hard to say
I and love and you
I and love and you
I and love and you

And that is how it’s done!

By the way, the song motif I think this follows is one of my favorites of all time by a Knight of the Realm, Sir Paul McCartney and “Let It Be.”

Wednesday, February 17, 2010

The Time I Got Applause for Fixing an Amplifier

Performers and musicians are used to getting applause for their work. It doesn’t seem fair sometimes that the rest of us work at our jobs, and no-one gives us a standing ovation. Of course, as a comedian once reminded us, we don’t get heckled at work either, so maybe it is fair. But this is the story of the time I got a round of applause from a packed room for fixing a guitar amplifier.

Some time back in the 70’s, I was at the old Wine Cellar in Longmont, Colorado listening to my good friends Casey Anderson and Bill Wienacht sing and play. I had recorded Casey many times and sold cassette tapes at his shows, but this night I was just relaxing and enjoying his music. Funny, I had recorded his songs and produced cassettes, so I probably heard every one of his songs over a hundred times, if not more. Yet I still enjoyed going and listening to him on “my night off” because he was such a great entertainer.

I was there with friends including the lady who would become my wife. Part way through the first set, Casey’s amplifier started cutting out. After a little pause and maybe a little swearing, he plugged into Bill’s bass amp, and the show went on.

During the next break he asked if I might take a look at his amp. “Casey,” I said, “you don’t get it. To troubleshoot problems I need tools and meters and maybe even a scope or signal generator. Plus, if I could figure out the problem, where would we get parts in a middle of the evening in a bar?” But Casey had confidence in me, and said, “I’m sure you’ll figure it out.”

I had noticed it was cutting on and off and so maybe the problem was something was loose. I looked into the back and noticed the tubes were not lit up. No power. I then noticed that the pilot light wasn’t on. So that was the problem. I checked the fuse, but no joy; the fuse was good. I switched power cords with the bass amp and confirmed there was AC power. Without a meter, I didn’t think I could do much more, but I figured I might as well drop the chassis out and take a look.

Fender guitar amps have a metal chassis, which is basically a rectangular box made out of sheet metal that is open on the bottom. Only, on the Fender amplifier, it is screwed to the top of the wooden case and speaker cabinet with the open end up, sort of upside-down. In the front, the chassis has the knobs, input plugs, and the pilot light that wasn’t lit. In the back are a few more plugs and switches, and the tubes are mounted pointing down, hanging into the speaker area. On the top are four screws that attach the chassis to the wooden case.

I took out my trusty pocket knife, and using the screw driver blade, I dropped the chassis. Logically I started with the pilot light. (That isn’t logical at all, but it did seem like a good place to start.) The pilot light is a low voltage bulb, typically six or twelve volts. It runs off the same transformer winding that provides the filament power to the vacuum tubes. The filament is exactly like the part of a regular light bulb that gets hot and gives off light. In a vacuum tube, the filament heats up the cathode to create free electrons, and that is the way a tube works. That is why tube radios and amplifiers have to warm up a bit before they play. The filament has to get hot, heating the cathode, and forcing it to emit electrons. The filament runs off a winding from the transformer which provides twelve volts to tubes like 12AT7 (that’s what the 12 stands for, filament voltage) or 6L6 (which uses 6 volts). The pilot light was in a little plastic socket with two small eyes at the end to attach the wires. That is where the power was connected.

Now think about how you might wire up your house. You could run a cable (wires) from the main power panel to the first receptacle in your house. Then run a second cable from the power panel to the second receptacle. And repeat that for every power receptacle in your house. But that would take a lot of wire. Instead of wiring each receptacle and switch box from the main panel, what the electrician does is run power to the first receptacle with a cable from the main power panel. Then he (or she) runs a cable from the first receptacle to the second receptacle, and then from the second to the third. I’ll bet you’ve opened up those receptacle boxes and you may have noticed there are always two cables running in. (Actually four wires, two white and two black … plus a green ground wire. But anyway, there are wires both into and out of each box except for the last box in the circuit.)

Well that is how Mr. Fender had wired this amplifier. The power came to the pilot light and from there it went to each tube socket to provide filament power. And guess what! The wire was broken loose where it was soldered to the pilot light socket. Most likely it was a bad solder joint from day one, but it was stuck in the hole and worked. It had finally wiggled out to the point that the connection was broken. If I had used a meter, I would have seen that the other voltages were present, only the filament voltage was missing. And without a hot filament the tubes didn’t work and neither did the amp.

Now I knew what to fix, and it wouldn’t need a part. Just a soldering iron and some solder. I asked the bartender if he had a soldering iron. After the surprising response that he didn’t, I realized a quick trip home was in order. I told Casey to extend the break a few more minutes and I would be right back. I rushed home and grabbed my soldering gun (no time for an iron, and the gun would work OK on the large pilot light terminal) and a spool of solder and I rushed back.

By now the patrons were a little antsy. They wanted to hear Casey play and didn’t understand what I was doing up on the stage. I quickly resoldered the connection and didn’t even bother screwing the chassis back in. It hung in place well enough that Casey could plug in and start playing.

As he started into his second set, I sat down for a cold beer. Suddenly Casey stopped playing in the middle of his first song, and quickly explained that I had fixed his amp, and the show would go on. As he pointed me out back at my table, the joint broke out into spontaneous applause. I stood to take a bow, and everyone jumped to their feet in a standing ovation. (At least that’s how I remember it, and nobody can say different. That's my story and I'm sticking to it.)

I never charged Casey for the repair. He was a personal friend, and besides, the applause was really more than I had ever gotten for any other repair in my life. To this day when I do a “real good spreadsheet,” I look around to see if anyone noticed. Maybe I could get a little applause! Or maybe I just need an audience here in my office!! I could serve drinks!!!