Hi there again,
In my pursuit to improve my knowledge on audio, I ask more questions on the physical operation of cone speakers and the "coupling" that takes place between it and the air.
As I understand it, cone speakers are extremely inefficient and a small percentage of electrical power is converted to mechanical energy. The reasons for this, again, according to my knowledge, are many. One, because the magnetic field and electrical fields are not 100 % efficient, there are eddy currents that reduce overall efficiency.
The suspension has resistance properties, the voice coil has power handling limits and too much input power can result in thermal compression. We also have the enclosure which dictates to a large degree how much overall resistance (or lack thereof) there is going to be within the system.
But the transfer of energy from cone to air is highly inefficent because the cone has mass and it needs to be large to excite a given amount of air. The air also has resistance to motion. Large cones are needed to excite large amounts of air.
Larger drivers can move more air easier because the effective piston area is larger and can "punch" a greater amount of air out in the time required compared to smaller drivers.
But is there something that I'm missing ? Horn loaded speakers have a good impedence match to the air because a large proportion of electrical energy is converted to acoustical energy.
But if someone more knowledgeable than myself (and I'm sure there are here
) can explain to me how cone speakers have a poor impedence match to the air (and if the reasons I cited have a large influence on it) then I would appreciate it.
Thank you.
--Regards,
