Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Cabinets-Speakers => Topic started by: guntherbuffalo on August 04, 2014, 07:00:53 pm

Title: speaker sensitivity calculation
Post by: guntherbuffalo on August 04, 2014, 07:00:53 pm

Hi,


I want to calculate the sensitivity of an old speaker but do not know the relationship between dB and watts increase to make the calculation. It is my understanding that modern speaker sensitivity is measured as db 1metre away from the speaker using 1watt power. The speaker info I have found says the sensitivity of my speaker is 96db at 0.4watts.


So...



If a speakers sensitivity is 96dB at 0.4 watts, what dB would the speaker be at 1 watt?

This is to help me compare the speaker sensitivity to the values given in the specs of similar modern speakers.

Thanks,


Paul

Title: Re: speaker sensitivity calculation
Post by: guntherbuffalo on August 05, 2014, 01:44:11 pm

Anyone?

Title: Re: speaker sensitivity calculation
Post by: sluckey on August 05, 2014, 03:44:00 pm

DB = 10[log(P1/P2)]

So, a power increase from .4W to 1W is +4db.

I don't know how that may relate to the sensitivity of a particular speaker. I think you would have to just do a lot of measurements and plot a graph. Or use a fancy analyzer that can sweep a range of power levels and plot for you.

Title: Re: speaker sensitivity calculation
Post by: jojokeo on September 10, 2014, 01:57:20 pm

Quote from: guntherbuffalo on August 04, 2014, 07:00:53 pm

If a speakers sensitivity is 96dB at 0.4 watts, what dB would the speaker be at 1 watt?

Or you d/l an app similar to "MrNoise" (free) on your iPhone and run your own tests w/out all the calculations and get real world results? If it's just for theoretical purposes what's the point?