Amplifie gain and limiter calculation

Hi

You can calculate output voltage beforehand when you know amplifier voltage gain and input voltage. This doesn't take account the voltage drop when load (loudspeaker) is connected. This way you have some starting point for setting limiters. Decibel calculations are bit tricky because of the logarithm involved.

I usually measure amp output voltage with pink noise and calculate rms power at 'speakers impedance minimum (driver mounted in enclosure, not in free air), then same all over for peak power with some percussive test track and measure amp output voltage with multimeter peak hold on. P=u^2/Zmin

I use both pink noise and signal with high peak content to see/hear how the limiters are actually limiting. Always start with lower limiter treshold than needed and measure few times, gradually working towards higher power levels. 

edit:Amp gains set to maximum if hiss or noise isn't problem. (so any curious person can't turn them up after your limiters are set)

Andy






Edited by AndyWave - 13 June 2011 at 4:02pm

Reckit, welcome!
I would be very keen to make use of this spreadsheet!

You won't be able to upload an xls file direct to the forum, but filesharing sites are freely available and simple to use. I'd personally recommend http://www.mediafire.com
Signing up takes but a moment then, once uploaded, a link to your file(s) can be copied to the forum...

Amplifier Gain Calculator -

Edited by Happy Jack - 15 June 2011 at 7:25pm

Edited by Reckit - 16 June 2011 at 11:23am

Thanks.

I will look into it.

Has anyone tried one of the above?