levels within pro tools?

[weezerboy]

Ive noticed that when i have the levels in pro tools higher, the sound seems to change a little bit. An example would be if im mixing and i like all the levels relitive to each other, but i havent been gain staging very well and i want to turn the whole mix up. If i group all the faders (except the 2mix) and bring them up a little the sound changes significantly, and not just the overall loudness. In im not getting any clipping meters lighting up either. It seems like the tone changes a lot. has anyone else noticed this? maybe its just me, or maybe thats something that happens everywhere, not just within pro tools. im not sure. maybe it has somthing to do with the plug ins, or maybe it has something logarythims or something. if i turn up all the faders so that the master fader is about 3db hotter, and then i turn the master fader down 3 db, should the mix sound the same or not... because to me it doesnt... thanks.

[Howardk]

Couple of things come to mind:

1. Maybe it is something in gain stages of your monitoring system. . . it can be easy to clip the first gain stage from the hot level output of a ProTools rig. I have seen it many times before. . . ProTools output is hot, especially when you use L2 etc. . ., the user turns down the monitoring systems big-knob to compensate, hmmm but there is some change in the sound or distortion (only it is from the input section of their playback system running in a non-linear region or clipping), and Digidesign gets falsely blamed. . . What is your signal chain between ProTools and your speakers? Do you have enough headroom along the way?

2. or you are adjusting levels on tracks that are being routed into bus compression. . . then yes, of course the sound of the mix will change as you adjust the level of a track or group of tracks because certain types of plugins in the downstream bus will react differently due to the level change. . .just as it would in the analog world.

[frenchman]

1- If you have Aux tracks dedicated to bus based effects (reverbs delay etc) with bus sends in post fader, then these returns should not be incremented with the rest
2- If some bus sends are set on pre-fader, then you should compensate the level increase on the channel, by a level decrease on the send...

Of course as HowardK said if you bus to compressors then you have to change threshold and ouput gain on the bus compressor to compensate

As for master fader inserts, they are post fader so they will react the same to all level increase

The truth is, don't worry about level scaling since this is not an analog mixer. (The pro tools mixer white paper by digidesign explains this very well). The only thing that can make a difference is if you use outboard insrts or reverbs because the dither algorithms can make audible hiss if you haven't got your gains right, but that is easy on most plugins to compensate for

oh and I hope you use 24 bit sessions...

[Andre Knecht]

To add to Howard and Frenchman’s good comments…

It is indeed possible (relatively easy, in fact) to distort a signal without having channel and plug-in meters displaying a clip indicator.

[frenchman]

It is indeed possible (relatively easy, in fact) to distort a signal without having channel and plug-in meters displaying a clip indicator.

I'm interested, in what circumstances have you experienced this ?
I rely quite a lot on clip indicators, but most "hidden" distortion problems I had in the past where linked to the crazy default 888/24 input calibration (+4 dbu = -18 db FS !), a thing of the past now since I use AD8000 and 96 I/O.

[Andre Knecht]

Put some high RMS signals through EQ with steep cuts and you’re bound to have things go south on you. Counter-intuitive, I know. And yet…

.

[righton041]

Well worth checking out this entire thread.

http://recforums.prosoundweb.com/ind...8/0/240/11473/

[weezerboy]

Thanks for all the suggestions everyone. The signal chain between pro tools and my speakers is pretty minimal. I monitor on genelecs and ns-10s. Sometimes i use a control 24 but i try not to. I know i really hate the control room volume on the control 24, but i seem to get the same effect with or without it.

It could have something to do with bussing tracks together and compressing the group, but i dont really do that a whole lot, so i think there's something more to it than that.

and yes, i do all the sessions in 48 24 bit.

[Extreme Mixing]

When you want to trim the whole mix up, or down, just use the master fader. It's much more accurate than using groups. You do have to check on master fader plugs because this will change the threshold on compressors and such.

Steve

[Stuart P.]

Could be your ears are very sensitive to the principles of equal loudness curves (google Fletcher-Munsen).

Maybe this explains the frequency perception differences. I've had this issue as well. The only thing that helped me compensate was choosing a standard monitoring level. Since I work in post, this is expected, actually it's mandated. Try using pink noise and a sound meter, and sticking to a fixed monitoring level for all of your mix work. You may find it translates much better.

Good luck,
S.