I read that Voltage Amplifier have high input impedance and low output impedance, and Current Amplifier have low input impedance and high output impedance. If this is true what is reason for this as I could not find one. FETs have high input impedance and can act as voltage amplifiers, I think this confirms that voltage amplifiers have high input impedance.
On the other [hand] when we come to Common Collector and Common Base Amplifiers, the former one high input impedance but have voltage gain of less than 1. Is that not violate the basic property voltage amplifiers?
Since it have high input impedance, should it not have high voltage gain?
Similarly the later one have low input impedance but have significant voltage gain and no current gain, again opposite to the property of current amplifier?