legoflog

Hope this thread is still alive.. somebody know if Logic has any function allowing to "thin the automation data" as PT does ? Like manys I move the softsynth filters alot, that gives and enormous amount of breakpoints, and the system slows down dramatically..... Anybody ? tanx

Hi David, good mornign from italy ! The post about Db and Gains was really clear and helpful, tanx a lot! The point is the difference between the meters and the faders, and I should have known that..... "When the metering a signal that is hotter than -10dBFS, the meter's peak indicator shows only "9.0", which might trick you into thinking that all of a sudden your signal is +9dBFS.. it's not, it's -9dBFS, and Logic gets rid of the "-" sign to add a period and a decimal, to show you more precision. NOW THAT'S TRICKY....! "When the signal goes into digital saturation, the metering shows "by how much the signal distorts" (in red). It gives you a reading of how many dBs you should turn your signal down to have the peaks at 0 dBFS." That's tricky also: now everything makes much more sense, anyway It's difficult for me to understand how the system can give information about something it can't measure...: if FS is 0, how can a +6 get noticed and specified ? 1) Anyway, if I understand right, in this case the metering doesn't show anymore the SIGNAL's DbFs value, but rather the amount of Dbs that the FADER should be lowered by. If that's it, whoa!!, I'm happy.. "Taking things further" Tanx, I'm alway there for that. "Note that Logic's Audio Engine uses floating point number to describe the value of the samples. That means that really, you can actually hit a channel beyond 0dBFS and not distort, as long as you bring the level back down at or below 0dBFS before going out of Logic." That's exactely what I've experienced: if I turned down the master fader by 6db the signal was coming out right, no matter the red light on the channel. And I guess that's even the reason why Logic can advice the user of being +6db over the FS. But now I want to understand deeper ! Please help me. I know that floating point means that the processing calculation can exceed the values permitted by string of 24bits, i.e. processing a 24bit audio file requests a 32bit system architecture. 2) If I had it right, that's the reason why Logic CAN TELL me that I'm 6db over, but i CAN'T LISTEN anything over 0dbfs ? If this is right, the only thing that's still confusing me is that the 0 value inf the digital realm doesn't come from a pure convention, but form the fact that is the value of a bynary digit with all the values 1: being this the situation, there's no way to even "calculate" any value over 0......aaaargh! If you have the patience to reply to questions 1) and 2) also....that would be very appreciated! tanx a lot, have a nice day

hi David ! tanx for your reply, but as far as I know, and I may be wrong, "+6dbFs" is a kind of non-sense or, in other words, a misguiding way of expression. Please help me to clear my mind about it ! that's the story I know.... 0 is the digital full scale level, and saying +6 should refer to something like digital trim, I think Portools too can behave in a smilar way: but technically speaking a digital system cannot have saturation, doesn't have any hysteresis curve or whatever, if the level it's too much hot (something like 3 consecutive samples ?) the system goes clipping or muting (like cd players do): so what a digital trim effectively do ? Why a cd-mastered song, with fader at 0level, gives a metering way over +6, i.e. the meter goes red for a long time ? This happens even with song with a wide dinamic range, not only with very compressed stuff like dance or rock music. I'll be grateful if you can help me understand ! cheers goffolog

Hi, got a question about Fader metering in logic pro 7.1 (never used any DAW at pro level before): in the reference guide the fader are said to express "db values", but since they go up to a value of +6db it's clear that this is not a DbFs scale....maybe Dbu ? The problem is that if I load a commercially-mastered song, and put the fader to the 0 position, the meter goes clipping, as the soundcard does also (2882 MH): please note that this doesn't happens if I load the same file in Itunes, even with the volume at the maximum level. I've found this out while trying to make reference levels between the soundcard and the analog-mixer, and I just can't make my head up. At the end seems like I need to put ther Logic's (master) fader volume to a value of-6 to get undistorted signal: I tried with this value because in the reference guide is said that Logic can have a +6db of headroom, wich anyway doesn't make any sense to me in the digital world. Hope that my explanation is not too confusing, pleae help, I just can't make a reference-wise signal path ! tanx ! goffolog