Axiom Home Page Forums General Discussion Technical Questions explan these specs please

Why are there 2 SPL specs on the speaker and what are the differences.

Also there are 2 freq response reads what are there differences

thanks

The SPL readings show you how loud a speaker sounds when given 1 watt of power. The measurements were taken with a microphone placed 1 meter away from the speakers.

The anechoic reading is taken in a specially designed chamber that absorbs all echoes. The other reading shows how the speaker would likely perform in any given normal room (where echoes add to its overall perceived volume).

For the frequency response, the two tests show you readings taken with different accuracy levels. For the M22ti, for example, the speaker can repoduce sound from 22kHz down to 60 Hz without going deviating more than 3 db in SPL. If you look at the second measurement, the db range is larger (from -9 to +3), so the range the speaker can reproduce is also larger (22kHz to 50Hz). The reading shows that at 50Hz the sound is as much as 9 db softer than at 60Hz.

im going to do my best at this...
The spl specs ar for a average room and in an anechoic chamber. In a chamber there are no reflections and the walls are covered in sound diffusing materails.. the whole rooom is. In an average room you have reflections and less sound absorbtion and diffusion, therefore you will get a higher efficiency rating.

For the freq response, one of them is plus or minus 3db from the 0db line (if youve ever seen a response chart you would understand what im talking about more) the other measurement is plus 3db minus 9db and you notice that the bass response drops lower which means that the bass is still there and the speakers can produce it, just not within the standard plus or minus 3 db range..

im sure alan or someone can help you understand better than i can. if i am even correct

Thank You for the explanations

I know which spl reading to use when comparing other speakers

but which freq responce should I use when comparing other speakers

thanks

That really depends. Many other companies don't qualify their freq. response data with a +/- db range. When comparing, it's critical to have a range for a comparison to mean anything.

For example, if you look at this Polk Audio speaker's specifications, it doesn't mention a decibel range. This is misleading, since we don't know how much quieter the claimed 28Hz lower extension is than reference.