All of them featured true grand piano action keyboards which, if you were a real piano player, were a delight to play.

In their brochures, Yamaha claimed their electric grand pianos were "compact" and "portable". I am not convinced! They measured at least 57 inches wide by 45 inches deep (front to back) and weighed as much as 313lbs! I guess that at a time when bands were going out with Hammond organs, Leslies, CS80s, multiple MiniMoogs, Mellotrons and so on, the CP piano was comparatively 'portable'.

The CP piano's sound was achieved using a traditional grand piano hammer action hitting real strings. However, Yamaha developed special strings that could be made shorter and require less of them but still be able to retain an authentic acoustic piano sound. So, unlike ordinary acoustic pianos that typically have three strings for each of the middle and upper register's notes and two strings for each of the bass notes, the CP piano used two specially designed strings for each of the mid and upper notes and just one string for each of the bass notes.

Of course, this also greatly reduced the internal stress and tension on the string frame which did not have to be as big or as strong (or as heavy) as an acoustic grand's. And because the sound was amplified electronically, the casework did not have to be designed for acoustic projection as is the case with acoustic pianos.

In all, the CP electric grand was a triumph of mechanical engineering.

It was a triumph of electrical engineering too.

Under each string was an independent piezo-electric pickup that was used to amplify the sound. This custom design eliminated any possibility of 'howl around' even at high volume and for most, this was more than adequate.

However, one 'golden ear' user preferred to have a set of pickups made by Charles Helpinstill fitted instead. Helpinstall had been designing and manufacturing high quality and specialised pickups for acoustic pianos for many years and his designs were used by nearly all the leading piano players of the '70s and '80s in their live acts. Charles says of this CP70 conversion "I only remember doing this once in the late '70s, and with no real improvement to the piano. The fact that the CP-70 has no soundboard pretty much confines it to a unique sound (for better or worse)". Helpinstill are back in business at helpinstill.com

Both models had a 3-band equaliser for LF/MF/HF tonal modification. They also had a TREMOLO effect built in. The CP80 also had a 3-way BRIGHTNESS switch.

There was also a master volume control and to the left of this were insert points where you could patch in your own effects.

In its heyday, the Electric Grand was regarded as an instrument in its own right and not just a portable alternative to a real piano for live use and many artists used them in the studio in place of (or as well as) acoustic pianos. Often this was for convenience (plugging in a cable is a lot easier than mic'ing up an acoustic piano) but often, it was used for its unique sound.

Of course, with the advent of high quality digital pianos (many from Yamaha themselves!), the CP series became increasingly redundant both live and in the studio and it was eventually discontinued in the mid-'80s. However, the Yamaha Electric Grands remain today as classic and innovative instruments with a classic 'sound'.

It has been used in the past by the aforementioned Peter Gabriel and also Abba, U2, Simple Minds, George Duke, Bruce Hornsby, Genesis/Tony Banks and countless others. More recently, the UK band Keane have adopted the Yamaha CP as their primary piano sound and it is a trademark component in their music - it's even the featured instrument image on their website!

The CP70 featured in Nostalgia is from my own re-conditioned CP70 and uses a full length sample every minor third and several program variations are available to re-create some of the more popular sounds of its era.