300b pse gain

[Princo]

Can someone tell me the gain (without feedback) of wad 300b pse

thanks

[John Caswell]

Define exactly what you mean by "gain", as most amp specifications specify a voltage input (mV rms) for a maximum wattage output at the clip point.

John

[Princo]

Thanks John,

I used this formulae: Gain(dB)=20log10x vmax/vsens

where Vmax= sqr root (power out x 4) = sqrt(16x4) = 8v

then gain = 20log10 x 8/0.38 = 26dB

is that about right?

[John Caswell]

So if the amp gives out 20 Watts into 8R. W=V^2/R so V^2 = WxR = 160 so V=13 Volts approx = 13000mV and say I/put sensitivity is 100mV
So gain is 20log 13000/100 = 20 log 130 = 20 x 2.114 = 42dB approx. This assumes impedances are equal which of course they are not!
That's how I work it out, but generally I don't bother, just check input sensitivity for watts out at clip out and that's it.

John

[Princo]

thanks john,

The only reason for asking is i have fitted subwoofers to my FR driver enclosures each driven by its own icepower 300 boards, and the output from the subs is quite low compared to the FR drivers driven by the 300b's, so i just wanted to know the difference in gain between the 300b and the icepower

Anyway I was able to increase the gain of the subs by playing with the output from (active)xover so all is well now.

Thanks

[bob orbell]

For bi amping and using a sub, unless the sub has a input volume control, the input sensitivity needs to be the same. Bob