Magnepan Speaker Efficiency

[Niles]

It seems that all Magneplaners have the same sensitivity (86dB/500Hz /2.83V) according to Magnepan's specs?

Does that mean you can use the same amp with MMG.s to also drive the 20.7's?

Also, can anyone please explain why Magnepan gives sensitity figures as 500Hz /2.83V instead of the industry standard of 1000Hz / 1 watt? Are they both the same?

[josh358]

Most Maggies do have about the same sensitivity (the .7's are apparently slightly more efficient than earlier models) and I've found that MMG's will happily gobble up just about anything you throw at them, assuming you like to play them that loud (most people don't seem to). However, the larger models will play louder without a sense of strain so in practice, I think bigger amps make more sense for them.

I'm guessing that Magnepan provides the sensitivity spec rather than efficiency because they're 4 ohm speakers and most good amps produce twice the power into a 4 ohm load. The sensitivty spec accounts for this, since it's referenced to voltage rather power or current. So with the same amp, you can expect an 86 dB sensitive Maggie to play as loud as an 86 dB-efficient 8 ohm speaker, whereas if they referrenced the Maggie to 1 watt the figure for the Maggie would be 83 dB.

Not sure why they measure at 500 Hz, but it shouldn't make a difference if the speaker is reasonably flat in the midrange. Maybe because the two-way models have crossovers in the 1 kHz region and some of them show dips in the amplitude response in that range, so they'd seem less sensitive than they actually are. Or are harder to measure accurately there because crossover lobes make the measurement position dependent.

[Niles]

Thanks Josh!

That cleared up some questions that were keeping me awake nights.

[lakesailor]

Originally Posted by josh358

Most Maggies do have about the same sensitivity (the .7's are apparently slightly more efficient than earlier models) and I've found that MMG's will happily gobble up just about anything you throw at them, assuming you like to play them that loud (most people don't seem to). However, the larger models will play louder without a sense of strain so in practice, I think bigger amps make more sense for them.

I'm guessing that Magnepan provides the sensitivity spec rather than efficiency because they're 4 ohm speakers and most good amps produce twice the power into a 4 ohm load. The sensitivty spec accounts for this, since it's referenced to voltage rather power or current. So with the same amp, you can expect an 86 dB sensitive Maggie to play as loud as an 86 dB-efficient 8 ohm speaker, whereas if they referrenced the Maggie to 1 watt the figure for the Maggie would be 83 dB.

Not sure why they measure at 500 Hz, but it shouldn't make a difference if the speaker is reasonably flat in the midrange. Maybe because the two-way models have crossovers in the 1 kHz region and some of them show dips in the amplitude response in that range, so they'd seem less sensitive than they actually are. Or are harder to measure accurately there because crossover lobes make the measurement position dependent.

Good post !