By Rob Pegoraro
Sunday, September 16, 2007

Q What is the "variable bit rate encoding" option in my music software good for?

AThe so-called "VBR" encoding available in most major digital-music formats lets you copy music more efficiently. Instead of using the same disk space for each second of a song ("constant bit rate encoding"), it will let a more complex passage take up more space than a simpler interlude.

The results should sound a little better, at least when heard through a good set of speakers -- not that non-audiophiles should feel compelled to re-rip every CD after selecting this option.

The only real downside to VBR is that a few ancient devices may not play these files.

To change your bit-rate setting in iTunes, go to the iTunes menu (in Mac OS X) or the Edit menu (in Windows) and select Preferences. Then click the Advanced icon, followed by the Importing heading; select "Custom" from the Settings drop-down menu and click the checkbox next to "Use Variable Bit Rate Encoding (VBR)."

Windows Media Player doesn't offer a VBR option for MP3 files, but you can choose one for Microsoft's Windows Media Audio format: Go to the Rip menu, select the Format sub-menu and pick "Windows Media Audio (Variable Bit Rate)."

Google Desktop wastes my time with Web searches when I need to find a file on my computer. How can I keep this program focused on my PC?

Click the small, downward-facing triangle at the top of Google Desktop's sidebar (or, if you don't use that, at the right of its search box) and select "Preferences."

When that page opens in your browser, click the "Display" heading. Scroll down to "Default Search Type for Search Boxes," select "Search Desktop" and then click "Save Preferences."

Rob Pegoraro attempts to untangle computing conundrums and errant electronics each week. Send questions to The Washington Post, 1150 15th St. NW, Washington, D.C. 20071 orrobp@washpost.com. Turn to Thursday's Business section or visithttp://washingtonpost.comanytime for his Fast Forward column.