Someone told me a short ram intake is better for higher rpm's, while the cold air intake is better for lower rpm's. Is this true? if so, why?

Someone told me a short ram intake is better for higher rpm's, while the cold air intake is better for lower rpm's. Is this true? if so, why?

I thaught it was the other way around, why that is, can't tell you, sorry.

Cold air intake is better overall (in the high and low end regions).