Kohlberg Kravis Roberts and Goldman Sachs on Thursday agreed to buy Harman International, the US maker of high-end sound systems, in an $8bn deal with a novel structure that will allow public shareholders to participate in the buy-out.

The buyers are proposing to pay $120 per share in cash, or a 17 per cent premium over Wednesday’s closing value at Harman, which supplies luxury car brands such as BMW and Mercedes with audio and video equipment.