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  #11  
Old 10-31-2008, 12:11 PM
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O.G. Killa O.G. Killa is offline
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Default Re: Best Recording Levels

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Originally Posted by DrFord View Post
I don't know how many times I have had client's cell phones -> specifically AT&T do that stupid rhythmic beeping sound before they ring, while the client is recording. But that's beside the point.

If you haven't experienced digital noise, then you are lucky.
I hate to break it to you, but you have yet to list anything that would constitute "Digital" noise. I think your ignorance is showing here. Everything from RF interference to a bad power supply are types of ANALOG noise. AND!!! turning your mic preamps up and recording with hotter signals will only AMPLIFY those noises, not mask them.

The example you site, quoted above, will get louder as you record louder. The cell phone interference is analog, and as such happens either before you get to your DAW audio interface or after your interface on your way to the speakers. Turning up the preamp to record hotter also increases these artifacts. Recording with LOWER levels will actually help to get rid of them since you are pushing them down closer to the noise floor of the system.

Anything at the same level or lower than the noise floor of the system gets "swallowed up" by the noise in the system. This is true for analog tape and for digital recorders. The difference is, the noise in digital recorders is 30dB to 40dB lower than that of any analog counterpart. So, recording your levels lower puts your analog noise down into that realm (and if it isn't swallowed up by the system noise it might very well get swallowed up by dither when you master to 16bits). Recording lower also gives you more headroom for digital processing when mixing.

Let me ask you this... if you record as hot as possible, what happens when you EQ something? If you are recording a signal up to -1dB, and then you boost any frequency band using EQ by more than +1dB you are clipping the signal inside the EQ.

Your "sterile digital" recordings are "sterile" because you are recording too hot. No tube preamp is going to help that, no matter how much marketing hype you read. You are getting all this clipping and harmonic distortion within your plugins and throughout your DAW because your level to disk is too hot. That is what creates a "digital" sounding mix.

If you are recording into your DAW trying to get your peaks as close to 0dBFS as possible. That is the EXACT same thing as recording to an analog tape and trying to get your levels to tape up to +20dBVU.

In the end it all comes down to voltage. Equipment designed to operate optimally at +4dBu do just that; they sound "best" when the signal is +4dBu or as close to it as possible. +4dBu on a Protols HD system (192 IO) is at -18dBFS (or -20dBFS if you use the B trim). If you don't believe me, but a volt meter. +4dBu is equal to 1.228 Volts. Test all of your "analog tube" equipment. You'll see that when a signal is coming out at 1.228 Volts, it is showing 0dB on the VU meter of the tube gear. When you send a 1.228 Volt signal into protools HD (192 IO) it shows up at -18dBFS.

When you are recording as hot as possible you are trying to push upwards of 9 volts (with peaks way above that) out of a mic preamp that is designed to operate down around 1.228 Volts. And you are pushing that 9 volt signal into a line input and A/D that is designed to be linear at or near 1.228 Volts. EVERYTHING about the mic preamps, line amps and converter go "out of spec" when driving the signal that hard. The frequency response is no longer linear and the harmonic distortion increases dramatically, yielding a "sterile" and unpleasant sound. It's compounding. The preamp adds harmonic distortions trying to output such a hot signal...the line input adds harmonic distortion trying to receive that hot a signal, your plugins will potentially add distortion (boosting an EQ freq for example) and then your D/A will add distortion to it because of Intersample peaks... and your line output will add yet more harmonic distortion trying to output a signal that hot and most likely the input of your power amp or speaker system will also add harmonic distortion since the signal is so hot as well.
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  #12  
Old 10-31-2008, 02:04 PM
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DrFord DrFord is offline
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Default Re: Best Recording Levels

OG-
Everything you said in your post was both informed and eloquent. I just wish you would have approached that last post without the "showing your ignorance," reason being that what you said made me hold you in a new light of respect simply for the information you were sharing with me. It's a shame it came with an insult.

D
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  #13  
Old 10-31-2008, 06:05 PM
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O.G. Killa O.G. Killa is offline
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Default Re: Best Recording Levels

Learning begins with humility. If you can't admit you are/were wrong, or if you can't admit that you don't actually know something, then you can't learn.

I DID originally post a reply and a correction to your first post without being harsh. It was you who chose to overlook the facts presented within my first response by adding your subjective rebuttal.

If you had just read my original post with the same intent as my second, and tried to learn from it, instead of trying to use subjective opinion to refute my facts, then my second post would never have been written. In a lot of ways, I would venture to say that little comment I made focused your attention on any information that followed.

I apologize if you feel that ignorance has negative connotations. It really doesn't, the Merriam-Webster definition is "lack of knowledge, education, or awareness". By saying "showing your ignorance" i'm not saying "you are stupid", I'm saying "your lack of education in this area is showing", which are two totally different things. Being a great musician/producer/arranger doesn't automatically mean you have to be a studied electrical engineer. If you aren't exposed to these subjects, how are you expected to know about them? You're not!

Last edited by O.G. Killa; 10-31-2008 at 06:07 PM. Reason: clarification
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  #14  
Old 11-03-2008, 02:10 PM
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Default Re: Best Recording Levels

Quote:
Originally Posted by O.G. Killa View Post
Being a great musician/producer/arranger doesn't automatically mean you have to be a studied electrical engineer.
So you admit I am great.
I accept.
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  #15  
Old 11-15-2008, 01:11 PM
spaceman spaceman is offline
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Default Re: Best Recording Levels

thanks for the responses everyone! I normally track in stuff about half way up the PT meter, so it seems that is a pretty standard and safe way to do it.
shame that this thread, like so many others, ends up degenerating into tit for tat arguments .....c'mon guys no one is trying to diss each other, let's just keep it friendly and informative!
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  #16  
Old 11-16-2008, 12:21 AM
digilogin digilogin is offline
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Default Re: Best Recording Levels

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Originally Posted by O.G. Killa View Post
If you are recording into your DAW trying to get your peaks as close to 0dBFS as possible. That is the EXACT same thing as recording to an analog tape and trying to get your levels to tape up to +20dBVU.

hello,

that is incorrect. you do not get digital distortion per se under 0dBfs.

also, you should feel free to recalibrate you interfaces to -15 or so if you are running too hot for your console or something.

recording reasonably "hot" does indeed have an advantage as far as resolution [more bits being used for the lower amplitude information resulting in more accuracy there].

you can feel free to pull back channel faders as necessary in pro tools hd.

nevertheless, trying to record all of your tracks so that every segment of the meters gets used at all times is not productive [or reasonably possible], and it can create trouble sometimes with plug-ins being overdriven. not all plug-ins have an input level control, so you can end up having to use a trim plug in front of the processing plug-in to make things work.

basically, it makes sense to record with as much resolution as you can practically and reasonably, without turning it into an obsessive thing. you obviously have different needs if you are recording overdubs by yourself than if you are tracking a band where the drummer may all of a sudden start playing 3 times as loud as he did when you were setting levels.

digilom
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  #17  
Old 11-16-2008, 01:51 PM
dcboucher dcboucher is offline
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Default Re: Best Recording Levels

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Originally Posted by digilogin View Post
also, you should feel free to recalibrate you interfaces to -15 or so if you are running too hot for your console or something.

digilom
This is a really good suggestion.

Many consoles (even the big boys) are getting pulverized by full scale digital recordings and the mixers are turning down line trims or just not noticing that their consoles are folding in on themselves. While driving a console a bit gives you some extra sauce, there is a threshold of diminishing returns met very quickly and suddenly your mixes end up airless and flat. While the difference between -20 dBFs and -14 on the input side may only mean one click of a stepped mic pre, that usually puts your mic pre at a happier, less likely to get cranky, gain setting (especially with ribbons). Also, the return to your console is lower. Unless you are working on a console with a linear fader, the resolution of your analog fader increases as it approaches 0 dB. Why not have your recorder's returns optimized for the console? Get all your faders in the most usable range. Want to drive the channel harder, turn up the line trim. Want to drive the stereo buss harder, turn up the makeup gain of your buss compressor or just push the faders hotter.

I know it accepted knowledge that most big consoles can handle +26 dBU, but across 24 or 48 faders? You've got two line trims on the 192. Set the one you don't use to -14 dBFs and experiment. You'll probably end up somewhere in between, but you'll find a use for those VU meters that were always pegged and those faders around -30 that change level when somebody breathes too close to it.

I also think that the meters on protools don't say it all. When recording, give yourself 1-2 bits of headroom, you deserve it.
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  #18  
Old 11-17-2008, 11:46 AM
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O.G. Killa O.G. Killa is offline
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Default Re: Best Recording Levels

Quote:
Originally Posted by digilogin View Post
hello,

that is incorrect. you do not get digital distortion per se under 0dBfs.

Excuse me? Your comment doesn't in any way relate to what I was talking about... go back and reread my posts, and if you need me to, I'll explain after that... I'm not even talking about digital distortion, I don't know where you got that from?!?

Quote:
Originally Posted by digilogin View Post
recording reasonably "hot" does indeed have an advantage as far as resolution [more bits being used for the lower amplitude information resulting in more accuracy there].
This is a common misconception about sampling... it's completely urban legend. There is no more "accuracy" recording hot than recording quiet. All you are doing is pushing your analog noise UP into the higher bits and in essence making your recordings MORE noisy by doing so, not to mention all the information I mentioned about VOLTAGE!!!!

If your mic and mic preamp have an SNR of 80dB, yet your recording medium has an SNR of 120dB, HOW IN THE WORLD IS RECORDING HOTTER MORE "ACCURATE"? It's the same accuracy... a bit is a bit, doesn't matter if it's the most significant bit or the 20th bit. So long as you are above the noise floor of the recording system it doesn't matter if your signal peaks at -2dBFS or -12dBFS. It's the same waveform regardless, one is not "more accurate" than the other because it was recorded hotter. All you are doing is driving your electrical components out of their ideal voltage range...which was the topic of my posts to begin with...
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  #19  
Old 11-17-2008, 12:22 PM
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Delta Music Belgium Delta Music Belgium is offline
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Default Re: Best Recording Levels

Please read some basic material about digital recordings. If you record at 24 bit at a level of -20 dBFS, it is the same as recording at 16 bit and losing the resolution of the highest 8 bits. Recording with a level as high as possible at 24 bit will results in a better sound with a higher resolution. You can compare it with taking pictures with thousands colors or millions of colors (what is exactly the difference between 16 bit graphics or 24 bit graphics). If your outboard mixing board or analog equipment can't handle the level, then lower the analog trim, or recalibrate your analog path, or MITB. It is not an urban legend, it is all about science and mathematics...

Btw, I have a PT 24 Mix with 888/16 interfaces and I have a PT HD 7 Accel with 24 bit 192 I/O's. They are all calibrated the same way at +4dBu. So I gain 8 bits of resolution with PT HD 7 Accel and the 192 I/O, recording at 24 bit, while the actual output level (in Volts) of both systems (16 bit and 24 bit) is identical. So this proves that recording at the same high levels at 16 bits (in PT Mix) or 24 bits (in PT HD) gives you 8 bits more of resolution and a better sound but not a higher output to your analog stage...
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  #20  
Old 11-17-2008, 01:11 PM
chris110000100101001 chris110000100101001 is offline
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Default Re: Best Recording Levels

Quote:
Please read some basic material about digital recordings. If you record at 24 bit at a level of -20 dBFS, it is the same as recording at 16 bit and losing the resolution of the highest 8 bits
Actually, -20 dBFS is the same as recording at 21 bit. You don't "lose" any resolution by not using up all the bits. It's still there, it's called headroom. It's the same as analogue - record your RMS level at -18 (or whatever your calibrated to). Peaks levels will vary. XXXdBFS = 0 VU is a nominal reference, not a ceiling.

I agree with O.G. Killa, If your analogue chain has a noise floor 80 dB down, this is the same as 13 bit resolution. Why record noise to the lower 11 bits? I'd rather have useful detail down there, reverb tails & such.
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