On Sat, 2010-08-14 at 22:51 +0200, [email protected] wrote: > On Sat, Aug 14, 2010 at 12:19:33AM -0700, Niels Mayer wrote: > > > The big issue with having the full 144dB range is that the "business" > > end of the slider is all at the top, > > I've never seen a real fader that has any practical resolution > below -80 dB: the next tick, 5mm or so down, is 'Off'. And most > don't even go down that much.
I'm sure most people on here know this, but the decibel scale is a relative logarithmic scale. Saying "-80dB" means that whatever went in was attenuated by 80dB, or 1x10E8 - if you put in a 1V signal, a 0.01µV signal will result. For normal line level, that would be 0.007µV, or 7pV, yes picovolts! At 24-bit sampling for full-scale line level (0.707V), the LSB encodes a value of 0.042µV, and at 16-bit sampling that becomes 10.8µV - well below what your attenuator is letting through. For what it's worth, the channel faders on my Yamaha O1v go down to -60dB, with "infinity" being the bottom stop. To find what the values discussed above would be at -60dB, multiply the voltages by 100. Gordon MM0YEQ _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/listinfo/linux-audio-dev
