In late 1975, CBS Musical Instruments decided to drop the Fender name from the Rhodes line of products, in order to establish Rhodes as its own brand. The Rhodes Suitcase Piano and Rhodes Mark I Stage Piano continued to be produced in 73- and 88-key configurations.

Aside from the new logos, there were two main differences between the "Fender Rhodes" and "Rhodes" Mark I pianos: the hammers and the tines. These differences were small ones, but they still had a noticeable impact on the piano's tone. The new hammers were completely plastic, reducing the weight of the piano while retaining the same shape and replaceable Neoprene tips. The tines featured a "swaged" design, tapered in a way that made them 4 times more durable than the previous generation. The combination of these improvements produced the more mellow, less bell-like sound heard on most Rhodes recordings from the late 70's.

Listen! 1979 Mark I Stage 73 EQ: Mellow (MP3, 219K) - Normal (MP3, 618K) - Bright (MP3, 524K) performed by Piotr Cieslik

Of the changes during this period, the enhancements to the Suitcase Piano's amplifier are the most noteworthy. The amp was now 100W stereo (2 x 50W), with pairs of 1/4" inputs and outputs for running the piano's signal to and from a mixing console. This made it unnecessary to mic the Rhodes amp in a live performance situation.

On the front panel, the concentric knobs were abandoned in favor of a pair of sliders for EQ and individual knobs to control the rate (Speed) and depth (Intensity) of the Vibrato effect. The 1/4" Accessory jacks functioned as a send (#1) and return (#2) for an effects loop.

The Rhodes Piano Bass was still available during this time, though it did not sell nearly as well as the Suitcase and Stage models. As in previous generations, the Piano Bass shared the same appearance and internal components as the full-size pianos.