Call me weird - and no doubt you will - but I often like to have my computer make random noise. The reason is that when I'm working at my computer on a piece of writing, I don't like silence. To stay focused, and to help drown out the distracting natural and artificial noises of the neighborhood, it helps me to have some steady sound proceeding in the background. That sound, however, must not involve human voices, such as radio or television. If Terry Gross or the Car Talk guys are on, no work will get done; instead, I'll listen to them. The same thing applies to music. Unlike many people, I can't tune music out; music as background doesn't work for me. Perhaps this is because of my classical training - I don't know - but whatever the reason, when music is in the air, I tend to listen. This phenomenon is especially troublesome, by the way, in drug stores and restaurants that use Muzak or "Easy Listening" or other pseudo-musical perversions; I can't stop listening, and what I'm hearing is horrible, so I typically run screaming from the place moments after entering. How people can actually work in such venues, or what restrains them from suing their employers, has always been a mystery to me. Everyone complains of the ghastly holiday music that pervades workplaces in the run-up to Christmas, but to me, the whole world sounds like that all year round. But I digress.
As I said at the outset, while working at my computer, I often want sound, but not speech, and not music either; and the solution is random noise. I'm referring here to sound that goes nowhere and has no discernible pattern, sound that is gentle and pretty and unobtrusive. Such sound has nothing to grab the mind's attention, nothing to remind the hearer of the passage of time; yet neither is it soporific or monotonous. This sort of sound, I find, helps to keep my mind alert and relaxed; it pleases me and warms the atmosphere, yet it leaves me free to focus on the task at hand.
There are a surprisingly large number of good random noise generators for Mac OS X. Yet most of them do not quite fit my needs. Jon Klein's Musik makes random notes, but uses just one instrument, and patterns rapidly start to emerge, so that it quickly becomes boring and annoying at the same time. (Klein is best known for his remarkable cross-platform Breve artificial-life simulation environment.) Composer Karlheinz Essl is single-handedly responsible for several interesting real-time music-generation applications. His FontanaMixer is an attempt to recreate a famous aleatory John Cage piece; it's remarkable, but it grabs most of your CPU, making it hard to get anything else done, and its sounds are raspy and clanky, involve a human voice, and are mixed with long periods of silence, as if someone were muttering while sorting through the garbage cans in an alley - not exactly conducive to great expository writing. His Seelewaschen is also quite CPU-heavy, visibly slowing down my typing rate; it involves a tolling bell reprocessed to give various raspy, chirpy effects - sobering, but not relaxing. Much more to my taste is Essl's now classic LexikonSonate, which plays a random but extremely musical and sophisticated piano; it stops and starts rather a lot, though, and the piano sound is rather percussive. Besides, the very qualities that make its output musically brilliant and intriguing militate against its use as subconscious background - it makes me want to listen.
Make the Mood -- By this point you're probably thinking to yourself: "I see what this fellow is after. He wants something more along the lines of Music From the Hearts of Space - hippy-dippy, mellow, environmental earwash. He wants ambient music." You're right; I do. That isn't at all the kind of music I like to listen to, but it's the kind of music I want playing when I don't want to listen. And that's why my favorite background random noise program is presently SonicMood, from Bit of Paradise Products.
SonicMood has all the right elements for me. It uses pleasant QuickTime instrument sounds, combined into small, gentle ensembles (no more than three different kinds of instruments), playing long tones in a variety of modes (scales), sometimes sounding rather like a cross between foghorns in a harbor and Palestrina on drugs. Each combination of parameters - number and choice of instruments, maximum polyphony, average duration and pause, amplitude range, and mode - is called a Mood, and you can edit existing Moods and create new ones. Not only is each Mood random, within its parameters, but SonicMood also cycles through its Moods, randomly or sequentially, at time intervals that you define. Thus SonicMood provides an ever-changing kaleidoscope of unobtrusive sound environments - and if you do find any of the moods objectionable, you can simply eliminate it. (SonicMood can also display images, but this isn't a feature I use; in fact, I usually hide SonicMood completely right after starting it up.)
SonicMood might not be everyone's cup of tea, but surely I can't be the only person in the world who occasionally wants this sort of sound to emanate from the computer, and in any case it has certainly been helpful to me in my work, and therefore, quite directly, to TidBITS. So, in the class of Tools We Use, I recommend it to your attention. The developer, John R. Hall, is very responsive to suggestions; he quickly added a Dock menu at my request, so that I could pause and start SonicMood without making it visible. SonicMood is just $10, with a 30-day free demo trial period, and is available for both Mac OS X and Mac OS 9; version 2.0 is available now, and version 3.0 should be released shortly.