Lordy, I love playing with Acid.

It's not the same, I know, as turntables, but I am on a budget and this is the best an old mix tape fiend has right now. I mean, my tape deck doesn't even work (actually, it's my receiver that's fuct, but potayto potahto).

I am not a power user. There are, likely, people who know more about this program than I do. All I hope to do here is pass on a couple of tips I've learned through my various mistakes with a program I never read the manual to. You, a legitimately licensed and experienced user of Acid, may have no need to peruse my idle ramblings on the piece of software that has dominated my life for the past year.

Strangely, it's not a video game. Strangely, it's not the aforementioned Fruityloops, which I consider a video game. A pretty video game, more representitive of actual drum machines than Acid; but, then, Acid was never meant to reproduce your 808. Acid is a loop factory, a canvas for sound, whereas Fruityloops, Reason, et al, are attempts at reproduction, and Logic (and ilk) are software studios. So Acid stands alone, destined to become obsolete.

Let me put it this way: I've never heard any legitimate musician lay cred on Sonic Foundry's (and now Sony's) Acid. I don't think you'll see Acid, as software, referenced in any of your record's liner notes. Acid is strictly amateur style3.

But it has this appeal. Like amateur pornography. Like MODs of yore.

Acid is a multitrack graphical audio assembly program, similar to Sound Forge (probably because it was made by the same company), but more geared towards the creation and manipulation of songs, rather than individual audio files. Acid deals with audio files in a few ways: it turns short WAVs (or substantially short MP3s) into loops, enabling the user to draw a drum beat across the screen; it processes MP3s (or substantially long WAVs) into one-shot tracks, providing the basis for a rough mix; and it can create beatmaps of long audio files, making it possible to match beats. Like an actual DJ. With real equipment. Sort of.

So it doesn't look like an 808. You don't have a row of faux LEDs counting off beats. What you have is an approximation of a recording and mixing console (with a central mixer, options to add busses, and as many tracks as your computer can handle) and a canvas, where you draw your loops and songs. I couldn't imagine using Acid for recording. There's a record button, but I've never pressed it2. Frankly, there are better applications out there, with their own steep learning curves. As a composition tool, however, Acid is pretty easy to learn, and very fun to use.

Using Acid

Congratulations! You've acquired your own, perfectly legal copy of Acid. Now what do you do with it? Drop some sound files in to the big grey area in the middle and take a moment to familiarize yourself with the layout. Your sound files appeared in the track area, on the right. When they appeared, a light grey row followed it in the large, formerly blank area. That is where you draw stuff. Try it! You'll note that all files are represented by their waveform. Loops will automatically loop, large files won't. Hit play (or the space bar) and your little ditty will start playing.

At the bottom you will probably see the explorer, a file browser that also lets you preview (a little roughly) audio before you drop it in the mix. This bottom area is also home to a useful tool called the chopper, which provides an easy way to cut specific sounds out of a single file (without going to your favorite audio editor or guessing on the canvas), loop them, and insert them into the mix.

The bottom half of Acid is also home to your mixer, where you can control the universal volume, observe your levels, and add busses and assignable effects. While watching your levels, the meter keeps the maximum dB encountered since the counter was last reset. To reset these values, merely click them.

By each track listing, you will note a universal fader, where you can control the volume, pan, and assignable effect levels. There is also a green button labeled Track FX where you can assign a VST plugin to your track. This is different from assignable effects added from the mixer because you can't control the level of these track FX at specific times in the mix. You can only generate the effect and let it run alongside the audio, making this option suitable for reverb or, if you're feeling saucy, a resonant filter. At the bottom of the track list is another fader for tempo.

If you don't like how your tracks are ordered, you can easily rearrange them by dragging them to your prefered spot in the tracklist. This will not change the play order or how Acid interprets your sound, it will just help you organize your mix. You can also change the color of the files (useful for separating mix elements or instruments, however you arrange your mixing) here. Hey, while you're here, right click on track and select Track Properties. Immediately drag this to the lower part of Acid. It will mingle with your chopper and explorer. This window is pretty important. It displays the entire waveform of the track, audio attributes such as bitrate, tempo, and file location. The Properties window is also where you can switch a file from loop to one-shot to beatmapped.

Wow. We haven't made much noise. How boring. Let's move to where the action is.

That loop or song you drew out before, take a look at it. Right now there's no changes in volume, pan, or effect. It sounds exactly as it would in an audio player. On either side of any section of song you draw, Acid automatically inserts gain fades. You can disable this by right clicking on a selection of audio and deselecting Quick Fade Edges. Quick fading may smooth out some sound issues you have, though, so I typically leave it on.

Acid allows you to control levels at specific points in the mix through the use of envelopes. Right click on a track row and explore the Insert Envelope submenu. Insert a volume envelope. You will see a blue line running across your track. Double click the line to add a point. Drag the point to adjust the volume, double click to reset to 0dB (relative to the fader: a file playing at -1dB will play at -2dB when the envelope is set to -1dB). This is how you fade anywhere you damn well please. Even places where there's silence. It's like you're John Fucking Cage!

Pan envelopes work in a similar fashion. Up is leftward, down is rightward, double clicking centers. The pan, however, is not relative to however you've placed it in the universal fader: the envelope overrides the fader, so keep that in mind if you're getting tricky.

Go down to your mixer. See the green button? Looks a little like the one on the track marker? This adds assignable effects, which can be controlled with envelopes as well.

Now it's time to go to your favorite audio editing program to slice up some loops. I use Sonic Foundry's Sound Forge, which is simpler than Steinberg WaveLab and pretty easy to get ahold of. Goldwave is some nice shareware for audio editing. Find your loops (a nice trick to use in Sound Forge after narrowing down a selection is pressing Z, which moves the selection edges to the closest points where the waveform terminates, elimitating pops) and meet me back in Acid.

Now: go hog nutz. Really, have a ball. Polyrhythms are fun. Making big chaotic drum messes is fun. Making soupy ambient tracks is fun. Acid can turn you into Fatboy Slim, Boards of Canada, or Prefuse 73. While that may not appeal to you, you'll just have to take my word for it: this making of music will enrich your spirit and make you more appealing to your prefered sex. The best way to tackle this beast is through experience. Strap on your headphones and immerse yourself.

The Art of the Mix MP3

I'm not much of a musician. I can sort of play a couple instruments, and I can sort of throw together loops and make them sound a little groovy. Mostly what I use Acid for is playing DJ -- making digital mix tapes.

Not everyone can afford turntables, vinyl, a quality mixer, etc. The rest of us are left with software and the free music we stole from the internet. Sukka DJs paid too much.

The most imporant thing in mixing is flow. With a stereo and a tape deck you record one song at a time, typically allowing a couple seconds of breathing room in between. And flow is important in its own way there but it takes on a whole new meaning with turntables and Acid.

There's a lot of tricks up Acid's sleeve. Most powerful is the beatmapper, a program that allows you to find the tempo of a song quickly and accurately.

It's easiest, of course, to do this with music built on loops. Human musicians have a tendency to wander, but computers and DJs (who are usually part robot anyway) are pretty good about keeping a beat. Find a good hip-hop or electronica tune and drag it into Acid. By default, Acid will ask you if you want to beatmap any large file (longer than 30 seconds, I think), but I usually turn this option off. You can start the beatmapper on any file by going to the properties box, selecting the Stretching tab (if your file is marked as "beatmapped") and pressing the Beatmapper Wizard button. The Stretching tab also allows you to adjust the tempo of the track in relation to the tempo of the project, if you feel you need to do it by hand.

Welcome to the beatmapper minigame! The object of the game is to define the tempo of a song by finding one measure. The first thing the beatmapper will ask you to do is place the downbeat. This doesn't have to be the downbeat of the song. It just has to be the first solid beat where you can define a measure. Look for a good solid bass peak. Next it will ask you to find a measure. A helpful cowbell will harass you until you find a way to make it blend in with the beat (just like a real DJ!). Click next and the beatmapper will take your tempo and apply it to the song and give you something a little different. Now you can inspect the song measure by measure to see if you're retarded or not. Go forward a few measures and fix any hiccups. Do this until you're at the end of the song. Now go back to the beginning. The tempo should still match up. If not, the tempo of the song probably wanders, and you're as close as you're going to get. If this is the case, fix the tempo to whatever part of the song you'll be mixing into and hope it agrees with the other end (you should be able to mix into and out of a song like this, but you won't be able to effectively lay it over anything). If the tempo seems perfect, you now have a deadly piece of forged audio, ripe for mixing. The mapper will ask you if you want to change the tempo of the project to the tempo of the song, and also if you want to save the tempo information with it (in the form of a SFK file, which Acid creates when it scans a file for peaks).

An important thing to keep track of while mixing is your levels. Clipping (any time your levels bounces to the reds) may not manifest when Acid plays audio, but it will when you render your song to a file. Clipping is your enemy, and it is your priority to eliminate it. I automatically set track levels to -1dB (you can choose your default track settings by right clicking on a track label and choosing Set Default Track Properties). Whenever you're mixing two songs together, you will have to adjust either the faders or the envelopes until all clips are eliminated.

Now have some fun. Your mix can be as long as you desire. Keep in mind some CD burners have trouble encoding more than 74 minutes, so if you want to burn one long mix, you're a little limited, but otherwise you're only kept in check by your available disk space.

Another thing you will find useful is the ability to change tempo midproject. 60 minutes of music at the same tempo is boring (to me, at least), and you may have some songs that change tempo. Or you may just want to bend tempo for musical effect. Whatever your reason, move the cursor to where you want to change tempo and select Tempo from the Insert menu. This will place a flag you can move around. Shift the tempo flag until you find a good place for it (between measures is a good idea).

Skillful use of the chopper can extend pieces of a song, providing ideal basis for beats to mix into (and out of). Select and preview your loop in the chopper, and add it using the / key. Easy peasy.

You now have the basic skills to start using Acid to make beautful continuous mixes that will impress your friends and earn you an honorary dictatorship in some third world countries. Huzzah!

Flaws Inherent in the System

Overall, I've been very happy with my Acid experience, but there are a couple things that bug me. You can't change the tempo of a single track midsong1. The tempo flag universally changes tempo, making adjustment for wandering songs impossible.

For some reason, scanning a file in Acid 4 does something to the ID3 tag that makes it so iTunes can't read it. Annoying, even moreso if iTunes automagically sorts your music collection.

Delays can't be set to coordinate with tempo, like in Fruityloops. All delays are drawn by hand, which has its advantages, but if you use one delay as an assignable effect in one part of a song where the tempo differs from the rest of your mix, you have to create another delay to use elsewhere in your project. Not a big deal, but still irksome.

Of course, the main flaw of Acid is that it's not a set of turntables. No way to manipulate sound with your hand, live. I'd imagine making a live mix with Acid would be nigh impossible (especially since there's only one audio channel coming out). You'd look stupid pressing play on your laptop and then standing there while expecting people to dance. There's no cred in Acid mix making. It's more of a toy than an instrument.

I'm sure you'll find more problems, but, really, Acid does just about everything I need it to.

Basic FX Rundown

These are the effects I find myself using most often. Acid's default VST plugins (the programs that define the effects) aren't as powerful as some that are available from Steinberg and other companies. I'm unfamiliar with these extra plugins because they never seem to install quite right (probably because I'm not paying for them). Anyway, a lot of Acid's defaults stink. The distortion is useless and there's definitely better compressors out there. A few are plenty useful, though.

Every track you open in Acid starts with a graphical EQ by default. Two others, parametric and paragraphic, are available and may be more suitable for your needs. Acid's EQ is just like your stereo's equalizer. When mixing a song, EQ is an important tool. Every instrument occupies a frequency range, and two tracks fighting for the same range will booze up and riot, destroying your composition. Balancing EQ takes a delicate ear, so if you're using Acid as a mixing suite for your composition, be prepared to squint your ears.

If you're using Acid as a turntable substitute, you may not want to mess around with EQ, since your songs have already been labored over by audio engineers, and you may be messing with a delicate equilibrium. However, sometimes you may want to add a song's airy vocals to another song's bassy beats, requiring you to cancel out some EQ.

Here is a handy list of what each general frequency range adds to a song:
  • 16-60Hz: Power. Sub-bass is the part of music you feel rather than hear. Too much sub-bass sounds muddy.
  • 60-250Hz: Rhythm and weight. Bass can be tailored to sound fat or thin. Too much bass booms, and distracts from upper frequencies.
  • 250Hz-2kHz: Low order harmonics. Boost to add a telephone quality to a sound. Too much 500Hz-1kHz sounds hornlike, while too much 1-2kHz adds a tinny quality. Too much mid, high or low, causes listener fatigue.
  • 2-4kHz: Speech recognition. Too much in this range from instruments can make this difficult, covering sounds formed with the lips like "b", "f", and "m". Dipping the 3kHz on instruments and slightly peaking it on vocals can make vocals audible over instruments without having to decrease instrument levels (or increase vocals).
  • 4-6kHz: Clarity and definition. Boosting makes music seem closer to the listener, whereas trimming the 5kHz range makes a sound distant and ghostly.
  • 6-16kHz: Overall clarity of sound. Too much causes vocal sibilance.
Octave by octave, that's:
Delay was popularized by early dub technicians like Lee Scratch Perry and King Tubby. Old tape delays placed a series of taps (read heads set to various gains) after the initial read head, producing an echo effect. If crappy ASCII art helps you visualize this sort of thing, here:
     _____                          _____
    /     \                        /     \
    |  •  |-->direction of tape--> |  •  |
             ^   ^ ^ ^ ^ ^ 
           read   \taps /

Acid's delays work the same way. You have two choices: single and multi-tap. Delays can be fashioned to add to the rhythm of a song by fashioning the taps in proper time, or placed willy nilly to create atmospheric effect. To calculate the length of a quarter note delay, get a stopwatch and count 25 beats of a song. Stop the watch on the 25th beat and multiply the time by 41.81. The result is the milliseconds required for a quarter note delay. Divide this number in half for an eighth note or multiply by two for half notes. For dotted notes, multiply your milliseconds by 1.5; for triplets, .667.

Acid's multi-tap delay has options for modulation and feedback. Too much modulation sounds wobbly, too much feedback will clip. Note that each tap in the multi-tap has its own gain and pan, allowing you to perfectly customize where and when your delay appears.

Reverb is really a single tap delay, an echo that adds "room noise" to a sound. Alvin Lucier plays with reverb in an interesting fashion on his piece I Am Sitting in a Room. You probably will want to be a little more tasteful than him, but think about a room or space. Reverb pre-delay indicates the size of that space. Acid provides numerous reverb depths to play with, from cavernous environments to metallic sounding ones, to warm halls. Too much reverb becomes evident and distracting. Subtlety is recommended.
Flange is produced naturally (as natural as a studio sound can be) by slowing a tape reel by pressing on the edge of the reel flange. Acid takes two identical sounds and reproduces one over the other, but pitch shifts them apart from each other to produce phase, so you get a spacy sound that I'm sure you've heard before (if nowhere else, then in Itchycoo Park, apparently the first public apperance of flange). Flange is great fun! Hendrix knew it and now so do you.
Resonant Filter:
Resonant filters let a frequency ring out more than the others, often producing noise, but it's nice for making songs sound like old time radio.

General Mixing Tips

  • Keep in mind the basic elements of a song: Foundation, the basic rhythm section; Pad, or sustained notes; Rhythm, an instrument playing counter to foundation (rhythm guitar, or a tambourine); Lead, vocal or instrumental; and Fill, which follows the lead. Any group of instruments which is playing the same rhythm comprises an element. An arrangement with all five elements (or even just four) represented simultaneously will sound crowded and painful. Spread out and balance your elements to make it easier on your liseners.
  • When placing a sound in a stereo image (through panning), remember your anchors are dead center and hard left and right. Your lead and foundation should probably be anchored in the center. Rhythm and pad should wander to the sides.
  • Close your eyes and think of panning your instruments like blocking characters on a stage. A play would be annoying to watch if some characters were standing in front of others all the time, blocking them from your view. The same thing happens in a stereo image. Spread out your instruments.
  • Pick a comfortable volume to monitor your EQ and levels. Too loud or too soft and your ears will be fooled.
  • Gross sounding vocals can often be improved by doubling them. Flat or sharp vocals can be smoothed out by doubling them and pitch shifting one track up or down, respectively.
  • To make an effect sound better, cut it. To make it sound interesting, boost. Better is usually nicer sounding than interesting. Mixing is often the art of careful subtraction.
  • Balance is the most important thing in any mix. There's a lot of things that can go wrong or sound awful. Be patient, be prepared to listen again and again to the same sounds, and don't get frustrated.
Useful Keyboard Shortcuts

  • space bar: play/stop
  • F8: toggle grid snapping (sometimes useful, usually annoying. I use it in the chopper, mostly)
  • F9: zoom in close
  • ctrl-F9: zoom out completely
  • /: while the chopper is selected, adds selection to the mix
  • v: add volume envelope
  • p: add pan envelope
  • m: bookmark
  • t: tempo mark
  • d: toggle editing tool (pencil, selection, and eraser are the most useful)
  • +/-: shifts the pitch of a selection up or down a step.

The Mixing Engineer's Handbook by Bobby Owsinski (highly recommended reading)
A year of making interesting mistakes with Acid 4.

1Actually, I figured out a kludge. You could duplicate the wandering track and stretch the duplicate up or down until the tempo fits again, then fade one copy into the other at an opportune point, but man what a pain in the ass, plus you'll probably get a flanging effect you may not want.

2Last night, for the first time, I finally used Acid's record function. Press the record button, adjust your input levels, and start recording. Acid records input to a new track that you can mess around with later. Something about the way Acid recorded the files, however, monkeyed with the way Acid plays files, so I had to reprocess the files in Sound Forge anyway, restart my computer, and go from there. It may actually work for you, though.

3Addendum: I guess Acid gets cred, and it's probably just me who's a poser. Since the inception of this writeup, Evanescence and Richie Hawtins have been pointed out to me as musicians who cite Acid as one of their tools. And how could I forget motherfucking Don Red?