At the time, JBL had developed the D50SMS7 as their first dedicated studio monitor. It consisted of the S7 home component kit installed in an industrial cabinet. JBL was having a very difficult time breaking into the market with this system until the Altec 605A introduction.

Eventually, Altec had to admit their error and reintroduce the 604 as the 604E Super Duplex. However, by then, the genie was out of the bottle. The close of the decade saw the development of two significant JBL monitors that expanded their customer base beyond Capitol Records