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TelePaul

TelePaul

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Has anyone noticed that cretain interface instruction manuals offer the following regards tracking?? Things like 'Turn the input as high as possible with overloading the signal' or worse still 'The ideal level is one whereby the overload LED lights occasionally'?? Has anyone else noticed this?
 
TelePaul said:
Has anyone noticed that cretain interface instruction manuals offer the following regards tracking?? Things like 'Turn the input as high as possible with overloading the signal' or worse still 'The ideal level is one whereby the overload LED lights occasionally'?? Has anyone else noticed this?
They almost all say that, it sometimes seems.

It's a combination of two things, IMHO:

First, on many of those manuals, that section has not been updated since the 16-bit days.

Second - and this one is *important* - many readers misinterpret passages that say things like "without overloading the signal". Not only can "overloading the signal" can happen long before the meters get pegged, but it can also mean "overloading the signal downstream in the signal chain".

Add to that the observation (based upon many, many such posts in these forums) that there are a LOT of new users that don't fully understand the difference in meter types, the difference between analog and digital meter readings, and that "dB" in and of itself is meaningless - that dBu, dBV, dBFS and dBRMS all mean very different things, and that a reading of "0" in one type of dB meter does not necessarily mean a reading of "0" in another, and it leads to real misunderstanding of just how signal level really should be dialed in.

I'm working on a graphic web app detailing metering and signal level gain staging even as I type this. At the rate I'm able to work on it, it'll take another two weeks or so weeks to finish, probably, but based upon many of the threads popping up here recently, it won't be a day too soon ;).

G.
 
i understand the differences in metering and the reasons why some say not to track hot with 24 bit. what i don't understand is why no one here actually tests their own gear to find it's limits (i haven't come across any tests any way). if you hear a difference, you hear a difference. if you don't, you don't. simple isn't it? how do you know when the actual clipping point of your analog gear has been reached? have you heard it? did you see it? can it be measured?

i've been here (steady) since 2004 and i don't remember any mentions of all this "24 bit too hot" talk until maybe a year ago. now we have all these loud moufs (yes moufs) running around saying that this is common knowledge that every newbie should have known since day one. as big as some of the heads are around here (not speaking of you Glen :p ), i find it hard to believe that no one has mentioned it before just a year ago, if they knew about it before then. after all, big heads like to boast about knowing important things. the majority of the big heads have been here well over a year.
 
TravisinFlorida said:
what i don't understand is why no one here actually tests their own gear to find it's limits (i haven't come across any tests any way). if you hear a difference, you hear a difference. if you don't, you don't. simple isn't it?
I myself can't speak to what was talked about here more than two years ago since I have only been here for about two years, but I can say that this topic of recording chain levels has been a hot one as long as I can remember here.

The thing that gets my attention often,Trav, is reflected in your quote above (don't take that the wrong way, I'm not coming down on you), is the implication that pushing to the "limits" is a good or a necessary thing. It's really all still a hangover from the days of limited signal to noise ratio when every dB of dynamics had to be squeezed out of the gear in order to keep the noise floor in the basement where it belonged. It's simply not the issue it used to be, and pushing gear to the limit before it starts misbehaving just isn't the advantageous tactic it used to be.

(The Big Irony these days is that we have more S/N ratio than most of us can use in our gear, even in the mid-range stuff, yet everybody prefers to squash the shit out of their recordings anyway, certainly to the point where those 144dB of digital and 100+dB of analog range are simply wasted.)

The best analogy I can think of is that most of us that own 6-cylinder or better automobiles that are 5 years old or less have speedometers that go well over 100 MPH and drive trains that will oblige us if we wish to push those gauges that high. But is that really how we want to drive it? (OK, I know some of you out there will respond with a resounding "Yeah dude!" :). I also know that those are often the same ones who want to push their RMS to -5dBFS :rolleyes:.)

But for most of us, we know that it's far better in terms of quality of experience, fuel economy, safety, maintenance costs, and legal practicality to not drive the kids to school and head over to Guitar Center at 115 miles per hour. It's no different with our gear. Just because we have a box that can be pushed to +8VU before we can hear it distorting doesn't mean that we should drive it that hard.

Running the signal at an even keel can go a long way to providing a better mixing, mastering and listening experience down the road.

G.
 
ok, maybe Massive Master knew something about all this a couple of years ago.
 
About the manual thing... Stricly speaking, if referring only to the converters, then pegging a converter as hard as possible without clipping does give you the highest resolution you can for the converter itself. I would guess that this is why the manuals say this. It is not their job to teach you how to use the rest of your rig. So, in that sense they are right, but in the big picture that would be bad advice.

As far as people only recently talking about properly using gain structure, this is no new thing. I have been saying this for years. It seems recently though that is has definately gotten more attention and has been brought up as a topic that resides more in the forefront of this BBS. My system has been calibrated since day 1. For the last 4 years it has been calibrated even better since I have been using consoles in which calibrating can actually be done.

The truth is that even newbies should be able to get this information on their own. The problem I see now is that more and more people are just buying gear and jumping in headfirst without any knowledge at all. If however they were to do a little studying on their own of the basics ( gain structure for example which seems to be beyond many people) they would actually come to these conclusions themselves. It is just a simple leap in logic from learning gain structure to wondering and discovering how the converters should be used. It is nothing new and there are certainly many people who have understood this for years now.
 
Good advice here. The reason I noticed it was because I was helping a friend set up his sound card, and I'm trying to save him some time and heartache by teaching him to get things right from the offset. I was using the metering system in Cubase LE - something I find hard to work with as it is - And I came across the quick-start guide he got with his soudcard.
 
dig back some posts and see who mentions that -6 peak is a proper 24 bit tracking level. ;)
 
SouthSIDE Glen said:
Just because we have a box that can be pushed to +8VU before we can hear it distorting doesn't mean that we should drive it that hard.


G.




" this one goes to 11" :p



:D
:D :D
:D :D :D
 
flatfinger said:
Glen , are you gonna make a corrected , more accurate version of the graphic you asked me about a week ago ??? That'll be very cool!!! :) :)
Was that the one from SOS? If so, yeah, I'm working on somthing in a similar style to the frequency chart I did a while back. It'll have a revised version of that metering chart with mouseover information and a user-selectable dBFS range, as well as a section that displays basic info on gain staging throughout the recording signal chain.

I've been wanting to do somethig on this topic for a while because it seems such a main problem area for newcomers to this racket, both on a comprehennsion level and on an actual results level. That SOS chart and it's "issues" were the tipping point for me to do this one.

G.
 
TravisinFlorida said:
dig back some posts and see who mentions that -6 peak is a proper 24 bit tracking level. ;)

What has this got to do with anything though? I personally only care about 1 peak number in dbfs domain.... 0

I prefer to use -18 as an average level (correlated to 0dbVU). I know that -18 is not the be all end all number but it leaves enough headroom that I rarely have to watch for anything except on the analog meters at the console. Using this keeps my preamp and my EQ circuit on the console from overdriving and gives me a precise reference point. It allows me to hit +18 on any given channel before clipping the converter. I am sure that Massive himself will be the first to tell you that gain structure is no secret that he alone invented and would never claim to be the only who seemed to be aware of this until recently. But I don't want to put words in his mouth, so maybe you could ask him yourself.
 
xstatic said:
What has this got to do with anything though?



I think he means -6dbfs avereage or rms.



South side : supercool :)
 
Just as an FYI...

Digital meters (well the vast majority of them) cannot accurately read the real peak which will be recreated at the DA. Close enough but not quite, which is another reason why headroom is a good idea.

In the graphic below you can see how the actual waveform that will be recreated at the DA is peaking higher than the digital meter can represent. The digital meter can only mark peaks at sample points, not in between.

The dots in the photo are what the digital meter will display, the actual re-created waveforms will at times exceed that. The only way to remedy that is to use do re-construction before the meter. I think some of the newer digital formats might do that (DSD?) not sure.

From Nika Aldrich's "Digital Metering" paper
 

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