TargetSpot will soon be expanding its network and growing its national sales force, thanks to a new round of $8 million in equity funding.

The funds will also be used to fuel investments in the company’s advertising technology, according to the company.

The funding comes from Union Square Ventures, Bain Capital Ventures, CBS Radio and Milestone Venture Partners. All the current partners, with the exception of CBS Radio, also participated in the previous round of funding, which took place in 2008. That CBS Radio is taking part is an indication that the traditional outlet is taking online radio quite seriously, writes Mashable.

Online audio advertising has become an essential component of the media buy for some companies, particularly the largest national and regional brands, says Jeffrey Glass, managing director at Bain Capital Ventures and TargetSpot board member. Glass points out that TargetSpot’s growth over the past year has “dramatically outpaced the market.” By investing more capital, the company will be able to deepen its national footprint and better serve its rapidly growing advertiser base.

For the coming year, TargetSpot plans to put more emphasis on providing ad options that offer “precision, engagement and high impact” across its digital audio network, adds Eyal Goldwerger, chief executive officer of TargetSpot.