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rogersnick · Posts: 14

Hi,

I have a question about a couple of things. First, DVDs. I've been ripping CDs for many years now and am quite familiar with it, though I haven't ripped many DVDs. I'm the kind of guy that likes to record lines from movies onto my computer and since I'm a perfectionist I'd like to get the audio through digital extraction as opposed to recording through RCA cables or something. I've noticed that when I rip DVDs and look at the audio it's usually very quiet (maybe -15 db). It doesn't matter what DVD ripper I use -- they all do it. Is there a reason why DVDs are so quiet? Also, it seems like Nintendo GameCubes are very loud. Why is there such a difference in standard db levels for different mediums? Thanks very much for any responses.

-Nick

ozpeter · Location: Australia Posts: 3200

I'd hazard a guess that DVD sound levels have to accommodate massive explosions, worlds coming to an end, cars crashing through supermarkets, and other such 'entertainment' and so a fair bit of the overall dynamic range is reserved for the necessary huge transients. I'm on less familiar ground with the GameCube but I imagine nothing subtle ever happens, so loudness is the name of the game (as it were).

Using CE you can of course normalise the level of your soundtrack excerpts, assuming you include no earthquakes.

- Ozpeter

MusicConductor · Location: USA Posts: 1524

I totally concur. DVDs are one of the few places left on the planet where dynamic range still means something--although some DVDs are now being mastered for "home" theater meaning less dynamics than the theatrical version. Pity. Nonetheless, most DVDs still bring you the full impact of the studio mix, should you care to calibrate your system to peak out at 100dB or whatever they've made it...

As we've bemoaned here on a number of occasions, no bigwig record exec wants their latest hot CD release to be the "quiet" one, and CD audio is getting killed more and more these days in the quest to be louder than the Joneses' CD.

ozpeter · Location: Australia Posts: 3200

My DVD player has a 'compress the sound' button. But at least you get to choose whether to compress it or not. If they'd included that facility on CD players from the outset, maybe we'd have some choice now over compression in that format.

- Ozpeter

teflon20 · Location: Australia Posts: 474

DVD sound levels are engineered for people who live in hollywood and have cinema's in there houses with explosive speakers. Smile

rogersnick · Posts: 14

Hi,

Thank you for your responses everybody! You have been helpful. My question now is: What exactly is dynamic range? I'm guessing it deals with surround sound and which sound(s) play on which channel and whatnot. Is this correct or am I totally off? Thanks!

-Nick

Graeme · Member Location: Spain Posts: 4663

MusicConductor · Location: USA Posts: 1524

Sorry, dynamic range pertains to all audio, live or recorded, and is not directly related to surround. In generalities it refers to how wide of a contrast there is between loud and soft sounds. When used specifically, it might refer to a specific measurement in decibels of how much the loudest sound is louder than the softest sound. Most pop CDs have almost no dynamic range -- less than 10dB, excluding fade-outs and between-track silence. A wide-ranging movie or a good classical CD can easily top 30 or 40 dB or more--which is probably what you're encountering. By contrast, real life has an even wider range: an absolutely dead quiet room may have a level of 10dB, conversation is 60 or 70, my daughter screaming in my ear when I tickle her must be near 100, and a subway, jackhammer, airplane taking off, rock concert--these are all over 100dB.

MusicConductor · Location: USA Posts: 1524

There we are, Graeme! You were replying when I was just getting started...

rogersnick · Posts: 14

Hi again,

Thanks again for your responses! You know, I once did the music at a wedding reception and was playing classical music and I had a hard time finding a good level that I could leave the music at because if I had it loud enough to hear it most of the time it would be really loud at the loud parts, but if I had it too quiet so that the loud parts didn't bust everybody's eardrums then you couldn't hear the rest of the song. Because of situations like this, isn't a high dynamic range not always a good thing?

Another thing is I'm somewhat confused about your decibel level explanation. I thought that decibels were written in negative form increasing towards 0. If that's the case, then why would a quiet room be at 10 db (as opposed to, say, -60 db) and a concert be over 100 db?

I'm sure it's blatantly obvious that I'm fairly new to the conceptual side of audio. I've been working with Cool Edit for over five years but only fairly recently have I gone into the actual concept of audio and everything. Audio is a huge hobby of mine, so I'm really excited about learning and I'm grateful that I have such nice help offered to me online! Thanks, guys!

-Nick

MusicConductor · Location: USA Posts: 1524

Those are good questions (and by the way, welcome, Nick).

You are right that a wide dynamic range is not always a good thing, and its appropriateness will vary with the environment. A stone-quiet concert hall or controlled listening room are always welcome places for such a thing, but not for dinner music, when you have a migraine, or in a classy department store wishing to have subtle ambiance. But if our concern is to accurately reproduce a musical performance, including the nuances and impact, then dynamic range should figure in somewhere. Unfortunately, in most cases audio CDs no longer are mastered to accurately do its job, which is amazingly ironic since it originally blew away all other consumer formats with its specs.

As far as decibels go, you're absolutely right, but we're crossing up two different ways of using the dB. When recording digitally it is as you say -- negative values that approach zero as loudness increases. But in acoustic measurement, 0 dB is a tiny, objective energy value that serves as a universal value. Above this value are positive numbers that express a true energy value in proportion to zero, all referenced to an absolute standard. Really, two completely opposite angles to a related thing.

Keep reading, use the help files and tutorials, and have fun. This is a great hobby/profession and its fascinations and rewards are endless.

--Bill

ozpeter · Location: Australia Posts: 3200

I was going to post some helpful links trawled from Google (seaching for 'decibel definition') but there are so many, you might as well rummage yourself. It seems a popular subject for elucidation!

- Ozpeter

Wildduck · Posts: 466

The only thing to add to the above is that dB as a number just refers to a ratio. It has to be related to something before it means anything. This is why you see things like dBV, dBm and so on. The suffix indicates what the ratio is relative to.

Graeme and MusicC were just using common abbreviations. Their advice to search for more info was spot on.

rogersnick · Posts: 14

Hey guys,

Thank you all very much for enlightening me. I've learned quite a bit about audio in the past few weeks and I'm learning more every day. I will research more on decibels and whatnot on Google. Thanks again!

-Nick

post78 · Location: USA Posts: 2887

Wildduck's first paragraph explained your dB question rather well. I'd just like to add that the values used in digital audio are called "Full Scale", and is therefor "dBFS".

ozpeter · Location: Australia Posts: 3200

I've got a disused hardware compressor across the output from the CD player in the lounge for 'dinner music' and cordless headphones for not waking the missus. But when I'm on my own it's time to bypass the compressor and crank up the monitors.

- Ozpeter

rogersnick · Posts: 14

Hey again,

First of all, what's a RNC?

Secondly, from the sound of ozpeter's post, there are actually devices that have the explicit purpose of creating a brick wall for music, thus solving the problem that I had when I did the wedding reception? Is that correct? If so, then that's pretty awesome. How much would such a device cost and what is some more information on them? Thanks!

-Nick

post78 · Location: USA Posts: 2887

The RNC is a compressor and is one of many used to control the dynamics of audio. Cool Edit has a device that does the same thing called a "dynamics processor". Check it out in the manual and search the forums to learn more. Also check out the "hard limiter".
Once you start to get a hang on things, search the forum for "overcompress" and "oh my god that's so loud it makes me want to cry, where's the tissue?" to learn about some of the drawbacks.

kylen · Posts: 290