Helios Electronics is a British professional audio company founded in 1969 by Richard "Dick" Swettenham, an engineer who left Olympic Studios in London to build custom recording consoles in partnership with Island Records founder Chris Blackwell. Fewer than fifty Helios consoles were built during the company's first decade, but they ended up at the center of an outsized share of rock history — installed at Olympic, Basing Street, The Manor, Townhouse, Apple Studios, Musicland in Munich, and the Rolling Stones Mobile. Records cut on Helios desks include work by Led Zeppelin, The Rolling Stones, Pink Floyd, Black Sabbath, Bob Marley, David Bowie, and Genesis.

The sound that built that reputation came from the consoles' mic preamps, which used custom Lustraphone input transformers, and a distinctive three-band EQ — the input section that would later be reissued as the Type 69 module. The original company ceased operations in 1979, and Swettenham died in 2000. In 1988, engineer Tony Arnold, who had been servicing the consoles, acquired the trademark and re-established Helios Electronics Ltd., later releasing reissue hardware including the Type 69 mic/line/EQ module in 2004 and a 500-series version of the Type 69 preamp/EQ.

The Helios sound is also widely available in software form: Universal Audio licensed the design for the Helios Type 69 Preamp & EQ Collection plug-in for UAD and Apollo systems. Helios is generally regarded as one of the defining "colored" British console sounds of the 1970s, alongside contemporaries like Neve and Trident.

Helios has 3 products cataloged on Equipboard, including Effects Processors. Their gear is featured by 7 artists, with the strongest followings in Rock, Pop, and Folk, World, & Country. Notable users include Jonny Buckland, John Bonham, and Tommy Lee.