 Some early emulation devices from the 1970s were criticized for their unrealistic imitation of the Hammond sound, particularly in the way the upper harmonics were voiced, and in the simulation of the rotary Leslie speaker effect.Refinements to Hammond emulations eventually led to the development of relatively light electronic keyboard instruments such as the Korg CX-3 (1980), and the Roland VK-1 (1980), which produced fairly realistic re-creations of the Hammond tone.While these instruments were widely used to replace the bulky Hammonds for band tours and club dates, jazz and blues keyboardists still tended to use vintage Hammonds for recordings, because the first clonewheel organs could not reproduce the tonal nuances of the old wooden Hammonds.