Quote:

Originally Posted by **BMWM3Rod**
I think you might be confusing speaker "sensitivity" and "impedance".
Speakers with lower "sensitivity" are harder to drive....in other words less efficient.
Read this about impedance.
http://www.audiovideo101.com/dictionary/impedance.asp
Bottom line..the lower the impedance...the more current draw from the amp. As a result...more wattage. However...more distortion comes into play along with heat and instability of the amp itself if driven with too low of an impedance. |

Ok, so I read through the discussion on Impedence.....am I being thick or what??

"Impedance is similar to a dam in a river. If the river is a circuit (to be a true circuit the river would need to run in a complete circle) then the water is the electric current. The water flows freely when there are no obstructions to resist the flow. The dam in the river resists the flow of water. By fully opening the dam there is no resistance. The further closed the dam becomes, the more difficult it is for the water to flow. A dam of 1 ohm would have very little resistance (although a damâ€™s resistance to water is not measured in ohms, impedance is and so ohms will be used for this example). As the damâ€™s resistance to the waterâ€™s flow, itâ€™s impedance, increases to 2 ohms it becomes more difficult for the water to flow. Similarly, as the damâ€™s impedance grows to 4 ohms and then 8 ohms and beyond it becomes more and more difficult for the water to flow. In an electric current, low impedance lets more current flow. "

TAKEAWAY: lower impedence = less resistance i.e. more current flow

"A well designed amplifier with a strong power supply will double the amount of power in watts that it sends to a speaker with each halving of impedance. For instance, an amplifier might send 100 watts to a speaker with an 8-ohm impedance. When the impedance is halved to 4 ohms that amplifier would send out 200 watts of power. In the real world, few amplifiers are actually able to double their power output as impedance halves due to limitations on their power supply and design."

"

TAKEAWAY: Good amp will provide more power as impedence lowers (without power supply constraints etc.).....makes sense....lesser resistance from speaker equals more watts.

CONFUSION:

"Additionally, few amplifiers are able to put out power for any significant length of time with impedances of 3 ohms or less (the amplifier must be able to supply huge amounts of power as the impedance decreases below 4 ohms â€“ in fact, many receivers cannot operate below 6 or even 8 ohms). "

**If lower impedence equals lower resistance, then why would an amp have difficulty putting out power with speaker with impedences LESS than 3 ohms.......... I thought lower impedence equals lower resistance which equals to more watts??**
Am I being thick??