Two private-equity firms have called off an $8 billion deal to buy high-end audio company Harman International Industries.

Kohlberg Kravis Roberts & Co. and Goldman Sachs Captial Partners cited a decline in the company's performance on Friday. Harman said in a statement that the buyers believed they are under no obligation to complete the deal because a material adverse change in Harman's business has occurred.

Under the terms of an agreement announced in April, KKR and Goldman would be allowed to walk away from the deal if Harman breached a clause in the contract after paying a $225 million termination fee. Harman said it had not broken the agreement but did not specify what reason the companies gave.

Harman, which struck the deal with both companies in April, owns various audio equipment brands including JBL, Harman-Kardon and infinity.

On Thursday, shares were trading slightly above $112 . However as rumors of the failed deal leaked to investors on Friday, shares plummeted. Just before the market closed, Harman announced that the buyers had called off transaction. Shares closed down more than $23, or 20 percent to $88.76.

After credit markets tightened over the summer, various private equity groups have looked to renegotiate or walk away from big buyouts. Recently the Carlyle Group private equity group and two partners got retailer Home Depot to reduce the price of its supply business by 17 percent, or $1.8 billion.

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