Watts needed to drive ELECTROSTATIC SPEAKERS

[Ikehgl]

What is the minimum powe needed tdrivM.L ELECTROSTATIC SPEAKERS

 

[kanewolf]

Did you read the FAQ -- http/www.martinlogan.com/learn/faq-electrostatic.php They recommend 100WPC .... You could use lower power, but you will not get the volume. The FAQ says they are pretty efficient. I have never owned a pair so I have no 1st hand knowledge.

 

[americanaudiophile]

Electrostatic speakers can present a difficult load to an amp requiring higher current than many other speakers. Power is made of voltage x current. The proportion varies with the amp. High quality amps will produce more current than lower ones even if the power rating is the same. An amp that is stable and produced twice the power as the impedance is halved is preferred but is more expensive.
The amount of power also varies with the distance your sit from the speakers and the size of the room, Since they are dipole speakers, firing backwards and forwards, this also affects how the power is perceived.
Most receivers will not drive this type of speaker well even if the power rating says it is adequate.

 

[ien2222]

That's not really true, perhaps with some other new ES's and ML's from a couple of decades ago that was more the case but today's ML's do not present much of a problem at all. According to ML, a lot of their recent customers (that they know of anyways) are using AVR's to power them and have no problems.

@OP: As for the minimum needed, it depends on how loud you want them to go. I believe the sensitivity of recent ML ES's are in the 89-91dB/2.83v/meter which is pretty average compared with other speakers. So, that means at one meter from the speaker, when 2.83volts is applied (which is basically one watt of power) they'll play at 89-91dB depending on the speaker which is pretty darn loud.

A general rule of thumb for in-room response is -3dB for every extra meter from the first up to 3-4 meters, otherwise it'll be closer to the -6dB for every doubling of distance for extremely large rooms i.e. -6dB at 2 meters, -12dB at 4 meters, -18 at 8 meters. Now if you want to add +3dB it requires twice the power so if you're starting at 90dB/watt, 93 is 2 watts, 96 is 4 watts, 99 is 8 watts.

So, say to want them to play 99dB during peaks at 3 meters with a sensitivity of 90dB in an average room. It'll be 8 watts x 4 (it's -6dB at 3 meters using general in-room response) = 32 watts. As you can see, it's not a lot of power for it to be pretty darn loud, it's why the minimum recommended wattage for the (new) ML's start around 20. I'd say pretty much anything over 65-80 watts/channel will be sufficient unless you are planning on running them consistently very loud at which point you may want to look at 120w/channel or more.