Soundcards line out level?

[Dxvideo]

Hi all,

I need an information to designing my GC's buffer.. The quesiton is;
Whats the output level of a(ny) PC type soundcard? Does it around 1000mV or lover? Because i must determine my new GC's input buffers gain. Its actually=2 and i need 970mV for my GC. So i need 485mV effective input voltage.
Do you think 2 is enough gain for me?
Thanks a lot in advance..

[DcibeL]

Line level signals (unless we're in the crazy world of car audio) are 1 V peak. So you have an absolute maximum of 2V peak to peak swing. Many soundcards are a fair bit below a 1 V line level at maximum output though. You could always download a tone generator program and measure the output to be sure.

the word "buffer" and "gain" should not describe the same thing. A buffer has a gain of 1, and works as a current source. Once you include gain in the equation, your leaning closer towards an active preamp. If you're just using an op-amp for this "buffer", then adjusting the gain is as simple as replacnig a resistor. If you don't have enough, or it's too much, 5 minutes later it's changed .

[Dxvideo]

Ok i see. I use an op-amp (TL072) for input level adjusting. Then i call it "buffer". Yes it has a gain (x2) so i made a preamp.. I do not need a current source and as you said i dont need a buffer! Under that situation do i need a preamp like this?
And another question; 2Vpp makes 1.4Veff. As i can understand for LM1876 input with x20 gain i need 0.976Veff. So i need a preamp for full output? Am i wright?
The "buffer" is like that;
Thanks a lot.

[sivan_and]

This can be a buffer with a gain of 2X