An Extra 3db Senstivity In Speakers Means?...

[Llyr Roberts 0]

Does an extra 3db of sensitivity/efficiency in speakers really mean

 

A 600W RMS speakers with spl 95

will have the same loudness as

300W RMS speakers with a spl 98 (+3db)

 

Thanks Llyr

Edited June 17, 2008 by Llyr Roberts

[djgb 0]

Hey syt mae? I dont claim to know a great deal about speakers all I do know has come from this forum THANKS EVERYONE :thanks: and u tube , but what I have learnt that the spl of a speaker is similar to clarity? pls correct me if I totally wrong, or how easy or efficient the speaker can push the sound out?

the higher the spl the louder the speaker will be even if its the same rms as others.

Also thought that to hear a distinctive loudness or change in volume if u like the db has be increased by 10 ? again pls correct me if Im wrong.

It may pay u to look thro the achieves of this forum for far more information on the subject or pay u tube a visit?

diolch tongue out icon

[TonyB 0]

Yes, a 3db increase is the equivalent of double the power.

 

A 10db increase is a perceived doubling in volume

 

A 6db increase is double the volume output but as the human ear becomes less sensitive as noise gets louder, it has to get to a 10db increase before it is heard as twice as loud (haven't a clue how they measured it or come to that conclusion though)

[norty303 0]

And to get 10db more you need roughly 10 times the power - assuming your speakers can take the power!

 

3db = 2x

6db = 4x

9db = 8x

 

If you're talking about bass cabs, then running 2 off the same channel and having the 2 cabs together will gain you 5-6db in total, 2-3db for doubling the power (most amps will give 2/3rds to double their output power when going from 8ohm to 4ohm loads - again, assuming they can run these loads and the cabs are 8ohm to begin with) and 3db for the acoustic coupling of the drivers/horn mouths (depending on type of speaker) being within 1/4 wavelength distance of each other.

 

This why, if you use subs, its better to stack the subs centrally and have the tops on stands. You also minimise power alley effect through cancellation nodes, compared to having the subs separated. This is what causes those very bassy areas, and seemingly bass free spaces in a room.

 

It's often cheaper to spend a bit more on a high quality speaker with better sensitivity, that you can run with a smaller amp, than have a cheaper, lower sensitivity speaker that needs a big, heavy expensive amp to drive it.

 

Funktion One sound systems get very high sensitivity out of the cabs, the F218 bass bin has 2 450w drivers, where most other equivalent manufacturers use at least 600w if not 800w+ drivers.

 

Also, big drivers that need a lot of power tend to lose a lot of power to heat at high levels due to power compression, so you start to get rapidly diminishing returns.