Compactron's integrated valve design helped lower power consumption and heat generation (they were to tubes what integrated circuits were to transistors). Compactrons were also used in a few high end Hi-Fi stereos.[1] They were also used by the Ampeg guitar amplifier company in some of their guitar amps. No modern tube based Hi-Fi systems are known to use this tube type, as simpler and more readily available tubes have again filled this niche.