Talking about BJT topologies: A common base amplifier is always given as an example of an amplifier with very similar characteristics to the CE amplifier but with the low input impedance.
It is said that the CB amplifier is commonly used in RF amplifiers in order to match the impedance of the wire carrying the RF signal. With "perfect" matching, we get 50% signal voltage transfer and 100% power transfer due to the seamless(?) edge between the RF cable and the amplifier creating no reflection. Correct me if this is wrong.
Why do we not care about this with other types of amplifiers? I.e., all of other frequency ranges in the spectrum. But for specificity, say the audio range. We always want the highest input impedance for the amplifier in order not to load the signal. Why does the signal not reflect due to the change in impedance?
I guess what I'm really asking is:
What causes the reflection? Why doesn't it occur with other frequencies? (if it doesn't)