Regarding O2 power capabilities I have one question - according to designer's site, O2 is able to produce 7.15V when powered from AC. In a same time designer states that max input voltage before clipping is 7.15 / GainValue.
Does this mean that when used with ODAC, which has 2V output and standard O2 gain options (2.5x and 6.5x) you can produce 5V on output at 2.5x gain? This will also mean if we want to reach that 7.15V limit with 2.5x gain, we have to use some other source capable of outputting cca 2.8V ?
Gain is a logarithmic value. The formula if I remember it right is 20(Log X)
X is the gain value.
To put that into O2 + ODAC perspective. If O2 is powered from an AC adapter It can supply as high as 7V to a load and if powered by battery can only go as high 4.5V.
7V(O2) / 2V (ODAC) = 3.5X
Means O2 can amplify ODACs sgnal at max 3.5X gain without clipping.
20 (Log 3.5 ) = 10.88 dB
I used this online tool to get the gain in V (http://www.sengpielaudio.com/calculator-gainloss.htm)