"I think the voice does that perfectly adequately without being imitated by other instruments"

This quote by Evan Parker suggests that the voice is an effective instrument in its own right and does not need to be imitated by other instruments. He believes that the voice can conveying feeling and expression in such a way that other instruments can not. He is suggesting that the voice should be appreciated and valued for its distinct qualities, instead of trying to replicate it with other instruments. He is stressing the value of the voice as an instrument and its capability to communicate feeling and expression. He is also recommending that the voice ought to be given its own space and not be eclipsed by other instruments. He is highlighting the value of permitting the voice to be heard and valued for its special qualities. By doing so, he is suggesting that the voice can be used to develop powerful and significant music.