The Italian-based Farfisa company is well-known for its combo organs of the 1960s. They are small, portable transistorized organs that were an alternative to the heavy Hammonds of the time. A direct competition to the Vox organs, Farfisa dominated the '60s combo organ market with its bright and buzzy-sounding tones. At their peak in the late 1960s, Farfisa was Europe's largest maker of electronic instruments.
In the early 1970s, the VIP line of Farfisas brought a new set of features to the marketplace. The Farfisa VIP has two 4-octave keyboards and a set of bass pedals. It has registrations similar to other organs, such as "Brass," "Reed," "Flute," and "Horn." The most unique feature of the Farfisa VIP was the "Synthe-Slalom" setting, indicated on the front panel by a picture of a man on skis! The "Synthe-Slalom" effect is a pitch-bend controlled by a foot pedal on the floor beneath the keyboard. It allows the player to glide the note up to the correct pitch by moving the pedal fully forward, and to drop it by pulling the pedal back down.
John Paul Jones only used the Farfisa VIP organ on one Led Zeppelin track, but it is a very distinctive contribution. In fact, it is one of the most interesting overdubs on any Led Zeppelin album. For "Dancing Days" on Houses of the Holy, Jones used this animated sound to add interest to the later verses (beginning at 1:38). The chord tones sweep up and down from the correct pitch, but slightly behind the beat, creating a rythmic effect, as well as a pitch glissando. (This glide is very similar to the unique "portamento" setting on many Yamaha analog synthesizers.) During the late 1972/early 1973 tours, the Farfisa was sometimes used on top of the Hammond organ, and was featured on "Dancing Days." On some shows, a very small Hohner combo organ appears on top of the Rhodes or Mellotron.