If you do as I describe above and cut so that your DSP will not clip you will still be capable of sending full output voltage from your DAC.
I do take slight exception to the headroom comments. Measurements are not required if you have a good understanding of what you are doing with boosts / cuts and channel summing but I always like to do them for confirmation.
I then adjust the DSP so that it will never clip by subtracting the net boost from each channel and usually cut another 1-2 dB for good measure. By comparing the two I can see how much net boost I have. Personally I make a frequency response measurement of the DAC output with no DSP applied (at some lower level, like -20 dBFS) and then make the same measurement with DSP applied. I think in particular the fact that summing two channels results in 6 dB of boost (assuming identical input signals) is probably something most people do not consider. You bring up some good points for those of us using DSP. I had to add an analog pre-amp to my system when I use DSP room correction in order to have enough voltage to drive my amps to full power. I am also surprised how much DSP eats up gain. I am starting to think digital clipping is more common than you would think when using DSP room corrections. Rather than running 0 dB sweeps and "listening for digital clipping" is there some other way to test for "digital clipping" more objectively and easily without disturbing the household? When creating FIR filters in Rephase and REW is there a way to know what level to create them at to prevent digital clipping and not rely on the Convolver Plug-in? Do I need to make level adjustments every time I add in a DSP plug in like the "sum to mono" plug in? Any ideas on "best practices" appreciated. Then yesterday I was using the Foobar 2000 "downmix to mono" DSP plug-in on some old stereo Jazz recordings and started to hear "digital crackling" and sure enough the "summed mono" DSP was causing digital clipping by adding 3 dB to the signal when summed. I lowered the Convolver plug-in level by an extra 3 dB and it eliminated the obvious audible clipping when sweeping. The other day I ran a 0 dB sweep and was surprised to hear several frequencies with strong digital clipping. The Convolver Plug in has "automatic level control" which I assumed would prevent digital clipping. I use REW and Rephase to create FIR filters for room correction and use the Convolver plug in with Foobar 2000.
0 kommentar(er)
