A flat ride is a ride cymbal

Ride cymbal

The ride cymbal is a standard cymbal in most drum kits. It maintains a steady rhythmic pattern, sometimes called a ride pattern, rather than the accent of a crash...

 without a bell, originally developed by Paiste

Paiste

Paiste, a Swiss manufacturer and designer, is the world's third largest manufacturer of cymbals, gongs, and metal percussion. Paiste is an Estonian/Finnish word which means "shine"...

 in the 1960s. Zildjian calls their examples "Flat Top Ride." A flat ride cymbal produces the tightest, driest, most controlled stick sound of all ride cymbals, but with an airy wash. The lack of bell makes this cymbal quieter and most suitable for jazz

Jazz

Jazz is a musical style that originated at the beginning of the 20th century in African American communities in the Southern United States. It was born out of a mix of African and European music traditions. From its early development until the present, jazz has incorporated music from 19th and 20th...

. Roy Haynes

Roy Haynes

Roy Owen Haynes is an American jazz drummer and bandleader. Haynes is among the most recorded drummers in jazz, and in a career lasting more than 60 years has played in a wide range of styles ranging from swing and bebop to jazz fusion and avant-garde jazz...

 was one of the first drummers to use a flat ride which can be heard on Chick Corea

Chick Corea

Armando Anthony "Chick" Corea is an American jazz pianist, keyboardist, and composer.Many of his compositions are considered jazz standards. As a member of Miles Davis' band in the 1960s, he participated in the birth of the electric jazz fusion movement. In the 1970s he formed Return to Forever...

's album Now He Sings, Now He Sobs made in 1968.