I'll probably make some people laugh... must be very basic for u guys... anyway, i have a question.
I own a pair of Rogers LS3/5a speakers...
I just received a gift: a Cambrige Audio Azur 540 amplifier.

Now, Rogers' impedance is 11 ohms. And the Cambrige power is said to be 50W/8ohms and 75W/4 ohms.

As you may guess, i know nothing about impedance. So what will happen when i put the two of them together?

Unlike radio antennas, no impedance matching is involved in amplifier-speaker connection. Impedance matching should never be done for speakers!

Audio amplifiers state the minimum impedance for speakers. If an amplifier states 8 ohms minimum, connecting 4 ohms speakers can cause overloading damage for the amplifier.

Since your amplifier accepts 4 ohms, 11 ohm speakers are fine. Just that you get lower power (loudness).