Starting with the 1959–60 season the two shows were merged into The Lawrence Welk Show, reverting to monophonic broadcasts.
The name stuck, and it became the most popular variety show ever.
The Plymouth show was the first American television program to air in stereophonic sound.
Due to the fact that stereophonic television had not yet been invented (it would be 25 more years before it would become standard), ABC instead simulcast the show on its radio network, with the TV side airing one audio channel and the radio side airing the other; viewers would tune in both the TV and the radio to achieve the stereophonic effect.
Welk's program was among a group of syndicated niche programs, others including Hee Haw and Soul Train, that flourished during this era.
(The success of Lawrence Welk and Hee Haw in syndication, and the network decisions that led to their respective cancellations, were the inspiration for a novelty song called "The Lawrence Welk-Hee Haw Counter-Revolution Polka", performed by Roy Clark, one of the co-stars of Hee Haw.) Welk retired in 1982; at the time of his retirement, he was 79 years old, making him at the time the oldest host of a regularly scheduled entertainment television series (a feat later surpassed by Bob Barker in 2003 and later by Betty White in 2012).
The primary sponsor of The Lawrence Welk Show was Dodge (automobile maker), later to be followed by Geritol (a multivitamin), Sominex (sleep aid), Aqua Velva (aftershave), Serutan (laxative), Universal Appliances (manufacturer of home appliances), Polident (a denture cleanser), Ocean Spray (fruit juice) and Sinclair Oil (automobile fuel) served as associate sponsors for a short time.
Once a couple of studios at the ABC Prospect and Talmadge facilities had been converted to color in 1966, the show moved back there. When the show was cancelled by the head of programming there, Welk formed his own production company and continued airing the show, on local stations and, often from 7 to 8 P. Eastern Time on Saturdays over some of the ABC affiliates on which he had previously appeared, along with some stations affiliated with other networks.In many markets, the syndicated Lawrence Welk aired before the start of network prime-time on Saturday nights (7 p.m.Eastern Time); also in many areas, it competed against another show that was cancelled by CBS and resurrected in syndication, also in 1971 — Hee Haw.In response to ABC's move, Welk started his own production company and continued producing the show for syndication.Some independent stations put it in its old Saturday timeslot, and in many cases, it drew higher ratings than the network shows scheduled at that time.