KELLNER: Peripheral thinking can yield great results

Whatever you buy when you buy a computer, the main system itself is but one aspect of the purchase. There are, even a novice will soon discover, accessories and add-ons that make a simple PC into a truly useful tool.

With the burgeoning market for all-in-one PCs and Apple Inc.’s iMac, as well as notebook computers by the carload, the question of a separate display may be less important than it once was. Items such as an extra (or different) keyboard, external speakers, even headphones for listening while traveling - all these and many others are worth considering when computer shopping this fall.

Two suggestions, based on recent tests:

c Bose Companion 20 speakers: A few weeks back, I suggested Antec’s Sounscience Rockus speakers, list price $199, were worth a look. The product is still a decent value, but the true audiophile - and many of the rest of us - will think twice, perhaps three times, if privileged to hear the incredible sound of the Bose Companion 20 speakers, a compact duo that will complement any desktop (or notebook) computer and deliver the kind of sound that, well, only Bose can.

Four years ago, I was astonished when Bose demonstrated its Computer MusicMonitor speakers at its Framingham, Mass., headquarters. The Companion 20 speakers, bowing at $249, or $150 less than the MusicMonitor’s original price tag, are at least as good as the 4-year old model now selling for $299.

As with any audio product I examine, the key is to see how many notes and elements of music are heard when a given piece is played. Whether it’s Beethoven’s 7th Symphony, as recorded by the great Herbert Blomstedt and the Dresden Staatskapelle, or Duffy’s soulful “Mercy,” or Herb Alpert’s theme for the 1967 James Bond satire “Casino Royale,” and just about anything in between, the Companion 20 speakers bring out incredible sound from a small package. Crank up both the PC and speaker volume and you could easily fill a room. Play something that’s thumping enough and the U.S. Geological Survey might register another seismic event.

I exaggerate, but only slightly. The Bose product does what computer speakers are supposed to do, and then some: reproduce sound so faithfully that it’s at times a bit scary to imagine so much power in so compact a package. Unlike the aforementioned Rockus, the Companion 20 speakers need no separate subwoofer to produce amazing bass, and the Bose speaker’s control module even offers an input for your iPad or iPhone, and a headphone jack.

For $50 more than the next-nearest competitor, Bose manages to swamp anything else out there in the marketplace. The Companion 20 speakers are likely to be an in-demand item during the holidays. I, for one, wouldn’t wait that long to buy them. Details at www.bose.com.

Microsoft wireless keyboard 2000: Getting a new or different keyboard for your computer is almost a given, it seems. Many of us want to swap out whatever comes with our computer, or we want to have something available when the notebook is “docked” on our desktop, or whatever.

My personal obsession (albeit limited) is for the “Calculator” key found on each of the many Microsoft Corp. keyboards I’ve used over the years. One press, on either Mac or Windows, and the calculator program pops up, ready for instant use. Apple’s keyboards lack this feature. Although a user could program a function key to mirror this, it’s a hassle.

But the calculator button is the only good feature of the $29.95 Microsoft Wireless Keyboard 2000. I’ve used it for a number of weeks, and no matter what I do, the wireless connection between keyboard and computer is spotty at best. I’ve swapped out the tiny “AAA” batteries, and when the connection goes, it’s gone. Removing and replacing the transceiver, the little device that transmits the keyboard’s signals to the computer is a help, but it’s a king-sized bother. I’ll wait for a better wireless keyboard than this one, even if the price is nice.

• E-mail mkellner@washingtontimes.com.