JBL 4312 Studio Monitors description help

I'm starting a new thread on this, didn't want to hijack Steve's thread on his outrageously excellent speaker giveaway.

Recommended Power Amplifier Range: 100 watts continuous
I assumed this was a starting point. Steve corrected me by noting he's used just 10 watts. So the 100 watts continuous is the ceiling?

I guess what I'd really like to discuss is the Sensitivity. I've heard this also discussed as speaker efficiency, is that correct? And exactly what is meant by speaker efficiency?

A plain-English explanation, or direction to a previous thread, would be most appreciated, TIA!

Dan

 

BTW, we can order JBL product at NorthernLightFX.

 

Technically speaking, sensitivity and efficiency are different things, but they tend to be used interchanably when referring to the sensitivity of loudspeakers.

Sensitivity is normally measured as the sound output (measured in dB) at a distance of 1 metre (that's just over three feet for the metrically challanged) with an input of 2.83 volts.

2.83 volts is equivilent to 1 watt into an 8 ohm resistor.

A speaker with higher efficiency requires less power to reach any particular volume level. That may seem to be a good thing, but like everything in engineering, there's no such thing as a free lunch.

 

While the speaker may be rated for 100 watts, the tweeter itself may be only good for 10-15 watts. Since most 100 watt "musical" inputs will have little energy in the tweeter range, this is not a problem. However, if the amp is driven into clipping, it may generate harmonic distortion, which does lie in the tweeter range. Now your "musical" input becomes less musical, and the tweeter may be seeing much more than 10-15 watts, with resultant damage.

Conversely, it is usually safe to exceed the recommended power, as long as the amp is putting out very clean sound (very little harmonic distortion), which will not overdrive the tweeter. I have a pair of these JBLs that I have been driving with a 250 w/ch amp (for the past 12 years) with no problems.

If you underdrive the speakers with a low powered amp, just make sure that you don't drive the amp into severe clipping. Remember, the amp's power rating is for CLEAN power - it is capable of generating much more distorted power, which is what will blow a tweeter.

 

i have these speakers, they can handle my 1400 watts amps without problems

 

The 4312 is really great!
what version do you have? i have the mk 2