Question

Speaker systems are typically rated by a resistance value (referred to as characteristic impedance), what resistance is this amplifier designed for?

What is the power delivered to the speakers in Watts?

Please explain!!!!!

Answer 1

We have 4, 6, 8 ohm speakers with this input impedance,but there are no 4, 6, 8 ohm amplifiers with this output impedance.Audio technology even for speaker amplifiers (power amplifiers), we use only voltage bridging.

"real" matching Z_source = Z_load is really wrong.

The specified source resistance Z_source is hidden in the damping factor D_F.
A damping factor of at least D_F = 100 is entirely in order. Loudspeaker and amplifier connections have a source impedance (amplifier) of Z_output less than 0.04 ohms, with a load impedance (loudspeaker) of Z_input greater than 4 ohms.

Z_source << Z_load or Z_output << Z_input or Z₂ << Z₁

Power amplifiers with an actual output impedance of less than 0.1 ohm. Z_out < 0.1 Ω.

Impedance matching (power matching) Z₁ = Z₂  is only used in telecommunications and RF technology applied to antennas.

The amplifier dont get to see speakers of given impedance and you can connect loudspeakers with different input impedances (8 ohms, 6 ohms, 4 ohms) to an receiver with no negative effects so as the impedance of any of your speakers does not go below 4 ohms. If speaker impedance is too low the weak power supply of the amplifier gets problems. Too much current will run through the AV receiver's output transistors, causing the receiver to overheat and shut down. If you get 4-ohm speakers, make sure your AV receiver is able to drive them easily.

The real output impedance (Zsource) of a power amplifier is usually less than 0.1 .

The amplifier power output 100 watts is at a specified load of 8 ohms.It means with an 8 ohm speaker, the maximum output power will be 100 watts.And the amplifier power output should be greater than the speaker power because amplifier power output is rated for pure sine wave and sine wave with distortion will have less than the rated power output.Speaker power is the product of voltage and current rating of the system.