/diy/ - Do It Yourself

>>1740292
maybe mixing is the more correct term. any time you put two frequencies through a multiplier (and amplifier offset voltages and open-loop gain do vary according to input voltage because transistors are non-linear), sum and difference frequencies are going to happen
if your power frequency level is over 100000 then I'd only be a little concerned over the very remote possibility of fS noise coming from the DAC and mixing with fSW of your switcher, then mixing again with the difference frequency, generating a nice screechy 4kHz whistle under your 48kHz playback. it would take a perfect storm of shit for that to happen so don't sweat it, just use LC and RC filters to keep your rails clean (maybe leave some spare pads and insert some 0Ω jumpers) and eat a healthy diet rich in vegetables. in case it does happen it shouldn't be too hard to patch out