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Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 6:41 am
by spektralisk

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 6:42 am
by mholloway
Image

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 9:17 am
by redglass
GillyDJ wrote:I've recently read things about -18db digital being equal to 0db analogue (practically at least, not sure about theoretically).

Basically, you are supposed to receive better results with your final mix if you do not allow any track to PEAK over -18db. Obviously the track's volume slider may not be at -18db depending on the source audio or midi instrument + effects but the peak must not be over -18db.

As most people start mixing with and around the kick I would assume the kick must be punching at -18db.

I assume the tracks will add up at the group, then the groups will add up at the master, giving you a master output volume way below 0db and hopefully something nearer to -3db to -6db ready for professional mastering.

Using this method also means your plug-ins are not supposed to be worked as hard giving you cleaner results.

Has anyone else heard of this theory and whether it actually results in a better mix? Some producers swear by it (some have a -14db theory as apparently analogue is between -10db and -18db and this is halfway inbetween).
check this: http://en.wikipedia.org/wiki/Headroom_% ... cessing%29

Best, Bastian

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 9:58 am
by Der_Makrophag
I wonder how all these analog emulations are dealing with this? What reference will they use? Or doesn't it matter?

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 10:03 am
by esky

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 10:30 am
by GillyDJ
It was actually Steve Mac (Masters At Work?) who said it on Twitter. He's been in the biz for over 20 years and has moved from analogue to digital so one would assume he has the experience to know what he is talking about! MJ Cole (UK Garage / funky house producer) also joined in.

@mrstevemac
Also any producers out there. The minus 18 db trick really works. Crystal clear mixdowns.

@mrstevemac
So many of you asked what the -18db trick is. Hard to explain in 140 characters but the basics are -18db in digital = 0db in analog

@mjcole
@mrstevemac -14db I thought?

@mrstevemac
@mjcole 18 mate

@mjcole
@mrstevemac have researched. looks like can be anywhere from -10 to -18.
Important bit is not cooking plugs as with analogue

@mrstevemac
@mjcole totally mate, all about not cooking them

@mrstevemac
So it means dont run your daw so hot and you will get more headroom instead of smashing everything.

Re: -18db digital = 0db analog

Posted: Thu Feb 23, 2012 12:24 pm
by jonathan harker
http://www.digido.com/level-practices-part-1.html
bob katz! nothing more to say! cheers!

Re: -18db digital = 0db analog

Posted: Sun Feb 26, 2012 12:22 pm
by garyd7
If you are mixing within any DAW, then the audio won't be using the full digital resolution, which depending on your bit-rate and what level the audio is can produce quantisation noise when this signal is then amplified to a louder more competitive level. Generally the lower the level and the lower the bit-rate, the lower the signal to quantise noise ration will be, which is not what you want.

However if you are mixing using enirely analogue equipment then you may be right, but for digital there is no reason not to use the full resolution available to you.

Re: -18db digital = 0db analog

Posted: Sun Feb 26, 2012 1:11 pm
by crumhorn
garyd7 wrote:If you are mixing within any DAW, then the audio won't be using the full digital resolution, which depending on your bit-rate and what level the audio is can produce quantisation noise when this signal is then amplified to a louder more competitive level. Generally the lower the level and the lower the bit-rate, the lower the signal to quantise noise ration will be, which is not what you want.

However if you are mixing using enirely analogue equipment then you may be right, but for digital there is no reason not to use the full resolution available to you.
If the DAW uses floating point arithmetic then there is no additional quantization noise from working at low signal levels. The precision remains constant over an enormous dynamic range.

The only time it matters is when you are interfacing with the outside world or if you are using a plug-in like a compressor that's designed to work at "normal" signal levels.

Re: -18db digital = 0db analog

Posted: Fri Jan 17, 2014 2:46 pm
by salatspinatra
That is how I understand it as well. I think folks get tripped up because some general advice for preparing a master suggest not touching the master fader which would be an issue when interfacing with the world outside your DAW if you disregarded the levels being measured through internal summing. Correct me if I'm wrong.

Also, the original post did misquote the general consensus which is rather to aim for signal averages, not peaks, at -18db (which only on a digital scale would be the correct nomenclature).

Re: -18db digital = 0db analog

Posted: Fri Jan 17, 2014 6:03 pm
by jlgrimes
GillyDJ wrote:I've recently read things about -18db digital being equal to 0db analogue (practically at least, not sure about theoretically).

Basically, you are supposed to receive better results with your final mix if you do not allow any track to PEAK over -18db. Obviously the track's volume slider may not be at -18db depending on the source audio or midi instrument + effects but the peak must not be over -18db.

As most people start mixing with and around the kick I would assume the kick must be punching at -18db.

I assume the tracks will add up at the group, then the groups will add up at the master, giving you a master output volume way below 0db and hopefully something nearer to -3db to -6db ready for professional mastering.

Using this method also means your plug-ins are not supposed to be worked as hard giving you cleaner results.

Has anyone else heard of this theory and whether it actually results in a better mix? Some producers swear by it (some have a -14db theory as apparently analogue is between -10db and -18db and this is halfway inbetween).
I've read an article that said -12db digital is zero on an analog console.

I don't think it matters much but the big deal is not trying to record right under zero db with 24 bit digital because it wastes headroom for useless readings.

Recording under zero was the practice with 16 bit digital because that didn't have much headroom when it came to mixing in the box.

Now we have practically infinite digital headroom with 32 bit and even 64 bit.

Also many analog emulating plugins operate differently at high levels but you would need to check the manuals or tech support to confirm.

Re: -18db digital = 0db analog

Posted: Sat Jan 18, 2014 3:00 am
by Tone Deft
you guys are getting it all twisted.

the lesson is simply to not cook your plug-ins with a hot signal. digital is fine but when it clips it sounds really bad.

also there are times when the guy that designed the plug-in had to pick a sweet spot of performance in terms of volume, that spot won't be at full scale, it's down from there. -18dB sounds like a good guesstimate or rule of thumb.

-18dB does not = 0dB analog. decibels are a relative term. on many of our sound cards we have the choice of running them at -3dB of headroom or -6dB of headroom, for example.

agreed on the final result being -3dB to -6dB when you hand it off to an engineer.

"dont run your daw so hot and you will get more headroom instead of smashing everything." is just dumb and probably why the Tweet conversation ended, probably with @mjcole face palming and wishing he hadn't gone there.

Re: -18db digital = 0db analog

Posted: Sat Jan 18, 2014 9:14 am
by andydes
Edit. Very seriously posted in the wrong thread.

Hope no one saw that.

:oops:

Re: -18db digital = 0db analog

Posted: Sat Jan 18, 2014 9:46 am
by invol
It is common practice to calibrate VU meters according to various reference levels.. 0 VU is commonly referenced to - 18 dB FS, but they do not equal each other according to any pure math. There are different dB measurements that correspond to specific a specific voltage, but this is not that sort of thing.

** I made a correction to my original post, meters are calibrated so 0 VU is equal to certain levels. 0 dBu is equivalent to .775 volts. **

Re: -18db digital = 0db analog

Posted: Sat Jan 18, 2014 1:46 pm
by Sage
I hate this often quoted thread as while it is useful for people who were moving to ITB digital from analogue hardware, it confuses things for people who have never worked with analogue hardware and only ever worked ITB.

-18dBFS is just a reference for people who are more used to working with 0dBU.