Small-cap stocks were lumbering upward with the broad market until the Federal Reserve's announcement that a key interest rate will remain unchanged dampened the gains. Among the stalwart soaring names, however, was Spectrum Brands ( SPC).

The Atlanta-based maker of Rayovac batteries and other products leapt 17.8% after announcing plans to sell an "attractive strategic asset." The company also predicted a year-over-year improvement in fiscal fourth-quarter earnings before interest, taxes, depreciation and amortization. Despite simultaneously posting a wider-than-expected adjusted loss for the fiscal third quarter, shares traded up 74 cents to $4.89.

The stock helped to prop up both the Russell 2000 and the S&P SmallCap 600, which were respectively climbing 0.6% and 0.5%.

Valassis Communications ( VCI) also lent support to the Russell 2000 after private-equity firm Delta Partners reported that it had dramatically upped its stake in the marketing-services firm to 9.1%, or some 4.3 million shares. Delta's prior Valassis ownership had been at 5.2%. Shares of the Livonia, Mich., company leapt 16% to $9.15.

And Maryland's CompuDyne ( CDCY) surged 27.2% after The Gores Group and Stuart Mackiernan agreed to take it private for $7 a share in cash -- a 32.3% premium to Monday's close. Shares of the security-systems company were up $1.44 at $6.73.

Heavily on the downswing, however, was forest-products company Pope & Talbot ( POP). Shares gave up 59.5% after the Portland, Ore., firm said it has failed to adhere to one of the covenants in its senior secured credit agreement -- a certain minimum in earnings before interest, taxes, depreciation and amortization. Consequently, it has entered into a six-week forbearance agreement "while it continues to explore options to improve its balance sheet." Shares traded down to 85 cents.

Semiconductor-equipment maker SRS Labs ( SRSL) tumbled 36.4% to $7.16 on lower-than-expected second-quarter earnings, and fellow tech name Rudolph Technologies ( RTEC) was off 23.5% after per-share income slid 32.1% to 19 cents in the second quarter. That's a penny better than Thomson Financial's average target, but both Piper Jaffray and Needham & Co. stripped off their positive ratings on the stock.

Elsewhere, San Diego's AMN Healthcare Services ( AHS) projected third-quarter per-share income at 27 cents to 29 cents. Analysts are seeking 33 cents. Despite better-than-expected second-quarter earnings, shares of the health-care staffer plummeted 22.5% to $16.84.