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April 10, 2008

MP3 & AAC: What you're *not* hearing

Hello my friends. Having recently completed a series of college broadcast seminars (and, with NAB underway in a matter of days) the question of 'audio compression' ALWAYS comes up. People always ask, "Is MP3 *really* that bad?" or "Isn't iTunes' original AAC better than standard MP3" and so on and so forth. Then of course, there are many who also contend that MP3, AAC(+) and the like are simply good enough because 'you're not losing that much anyway'... Uh huh. Yeah, I don't think so. ;)

So, in an effort to 'visually' demonstrate what you're NOT hearing when you compress (using a variety of popular formats), I decided to pick a few cuts from one of my more recent FAME outings in Amsterdam...

The subject in question...Coltrane, with Elvin Jones/Jimmy Cobb on drums, 1959/1960

The Subject of Today's Lesson

Now, many may ask why I chose this particular record. Well, the benefits of well-recorded (and for that matter, remastered) Jazz albums is that you tend to have a lot of stuff going on in the 'high end'...and in this case, you've got some nice, present hi-hats and sizzle cymbals. Sizzle Cymbals are the ones that have the little rivets drilled into them. Used like a ride, they literally 'sizzle' as you strike them. This provides a really 'atmospheric' kind of sound, but also one that tends to resonate for a long, long time (and has a really nice decay). As such, it also occupies a lot of that high-frequency space.

So, let's take a look at what the upper register (approx 16k-22k) of this recording looks like UNCOMPRESSED. Sorry that these darned images are so small (limitations of my blog...anyone offering to help me 'pimp' my blog's CSS?? Greg is probably furious with me right now! lol) but if I get requests, I'll post larger frame size versions directly on my Photobucket page. Just comment me and let me know. This CD was ripped directly into Audition 3. We're looking at the Spectral Frequency Display in the Edit View, with 16k-22k zoomed in.

Coltrane Uncompressed, 16-bit Stereo, 44.1kHz
Uncompressed Coltrane, 16k-22k

As you can see, there is a good deal info above 16,000Hz. And, more importantly, you can truly SEE how strong (and present) that foot-closed hi-hat is (on the right channel, ie, the bottom of the image; top of the image represents left channel). There's plenty of that sizzle-y 'atmosphere' as well, as represented by the reddish-purple color. It's not high-amplitude...but it's THERE...and it's that very presence that gives the recording it's ambience (an essential factor for good jazz recordings from this era).

So, now that you know what you'll get from CD, let's now take a look at the NEW 256Kbps AAC that you can get from iTunes (these are the newer iTunes Plus files-- you can also rip directly into this format via iTunes).

AAC 256kbps, iTunes Plus
256K AAC , 16k-22k

Now, this is pretty difficult to see in these images, but what you've got is audio information that actually extends *nearly* to 19k on the average (best viewed on the left channel) with transient material (the initial attacks of the hi-hat) extended to approximately 20k (on the right channel). This, I must say, is pretty darn good, and for most ears you probably won't be missing much. Granted, this is *not* lossless...and speaking as a mastering engineer, I can tell you that in certain passages, you do get some weird artifacting and aliasing (largely because of those difficult sizzle cymbals; you are, after all, sacrificing sizzle and ambience for smaller file sizes)...but on the whole, it's a pretty sweet type of compression. As mentioned, I *only* started buying iTunes albums when iTunes Plus became available (and you'll see why in just a moment). Still, it's NOT replacing CDs for me

So, I'll give AAC 256 a B+/A- grade. Let's see the popular MP3 format...

MP3 @ 192Kbps (slightly higher than most internet audio encodes)
192k MP3, 16k-22k

Now, here's the deal with everything above 128Kbps in MP3. You basically get a flat-top, razor-edge at 16k...*but*, above 128 you *do* get transient materials that extend nearly up to 20.5KHz. So what does that mean? Well, it means that your ears hear the initial 'attack' of the hi-hat (in it's hi-end glory) but any decay of said instrument is truncated, and all the high ambience is compressed away. What you will also notice (if you listen carefully, with phones, assuming no hearing loss or damage) is that you *will* begin to hear some swishy, phasey-type sounds in the high register, again, all because of the compression. I used to use 192 for reference files (back when broadband was still a luxury)...but now, I *never* use anything less than 224, and generally I'll do 256Kbps if I'm sending someone an MP3.

But...the *best* (not) is yet to come. Again, I know so many people who've ripped and done away with their CD collections...and they ripped everything into the the native AAC format in iTunes. Well, check it out...

Old-school..AAC 128 (standard iTunes downloads)
128k AAC, 16k-22k

Sad, sad times, eh? What do you get? Well, for one thing, you'll notice (aside from the channels inadvertently being swapped when I ripped this! Bizarre) that now you have your 'ambience' resonating no higher than approximately 17k, with your transient attacks only extending to around 18.1k. Period. Nothing above that. WHA?? I mean, come on people!! You will also hear (very clearly) lots of swishy/swirleys in the upper register...but that's only half of the devastation of 128 AAC. ;( In short, if you've ripped your library in this format, you've thrown away more than just the sizzley-hissy high end. You've also lost a great deal of the 'meat' in the middle (the mid frequencies, where the primary fundamentals of everything live)... I'm crying tears right now!

Continue reading "MP3 & AAC: What you're *not* hearing" »

June 19, 2007

My, what a big (voice) you have!

You know, everywhere I travel, no matter what kind of CS3/Production Premium material I'm presenting, people are always inquiring about recording voice-overs. Without fail, I'll have at least 3-5 people (on average) asking about 'best practices' for not only capturing the recorded voice, {Is a USB mic plugged into my laptop good enough quality?} but also on how to actually 'mix' and 'master' the voice so that it sounds, well, like a broadcaster!

Now, I always tell people...there aren't any special tricks that are suddenly going to make you sound like 'that movie announcer guy' (note: for my European and Asian friends, there's a guy in Hollywood named Don LaFontaine, and he's responsible for about 90% of all movie trailers and TV sitcom VOs; he's THAT guy, and you'd know his voice the second you heard it!)

So first, what can't processing do? Well, for one, you can't add grit and age if you don't have it; in other words, if it's not there to begin with, you're only going to be wasting time 'attempting' to 'simulate' a certain sound, and I can honestly say, no one's really going to go for it. Obviously, you could take up smoking, suck down a pack or two and THEN do your voice overs! Certainly, it'll give you a bit more 'rasp' and a little 'grit'...but I certainly wouldn't recommend smoking, and, well, that's a bit extreme, even for me! (however, I've known guys and gals who've done it...again, I DON'T recommend this!) Also, if you've got a fairly 'pitchey' kind of voice, or you tend to speak in a fairly monotone kind of way, processing is not going to add 'life and personality' to your voice. That really has to come from within. (read on: it's all about 'belief')

Now, keep in mind that back in the day, to be in radio and broadcast, you had to have PIPES (ie, big voice, big presence). PIPES were the essential characteristic for *any* up-and-coming radio personality. But over the years (largely, since the mid-90s), it became apparent that the (older) dudes with the big voices really just didn't speak to most people, not anymore. That's not to say that having good pipes (ie, low, bellowing, mysterious, 70s late-night-disco voice) won't get you work...it's just that most radio DJS, and most radio personalities that do commercial Voice Over work are typically 'regular' people voices. They sound young (though age is rather subjective, and doesn't really matter, especially given the subject matter or product), they sound motivated (somestimes, TOO motivated, but high-energy is must), and they DON'T sound like a used car salesman (again, see: 70s late-night-disco-voice man). It's all about trust, you see...and, for good or bad, the 14-42 year olds just don't really 'believe' or 'trust' those old-school pipes anymore. Again, that's not to say that NO ONE is doing it (there are still a few great classic voices out there, and if you've got a legacy, you can keep going), but really, it's all about BELIEVABILITY and selling YOURSELF (and your naturally-inspiring tones) moreso than putting on a faux-midnight voice and trying to make the ladies swoon (guilty, as charged! I actually have tapes of me doing radio voice-overs at age 12. You WOULD NOT believe your ears. And yes, I was doing 70s late-night-meets-Barry White-voice! llol)

Now...what can good vocal processing do for you? Well, for one, it can make your voice a little bigger, a little louder, and it can even out your (potentially) uneven dynamics...which, right away will make YOUR voice-over sound ten times more professional than your friend who recorded his or hers WITHOUT evening out the dynamics. This is often achieved with a little compression and/or limiiting...but a little goes a long way, and the pay-off is dramatic and 100% professional and broadcast ready. It can also add that needed sparkle and presence, particularly in the mid, and high-mid EQs, just to give you that additional 'polish', even if you're not on an expensive microphone (again, the power of good digital filters....Audition and Soundbooth)

So...now that I've given this massive text introduction, I'm sorry to say that I'm having some kind of problem uploading screen shots (which is essential to the next part of this voice-over lesson)...so my blog, though long and wordy, will have to end here for now!! (aww...I make you read all the way through and then don't give you the goods?? Well, in the words of Elvis Presley, circa 1969 in rehearsals for his Vegas International Hotel premiere, "That's just the way it is." ;)

Bare with me, my friends. I hope to get this sorted tomorrow or the next day. Hang in there, and remember...it's all about selling 'the belief'. If you believe it, well, your listeners will believe it too...don't you believe me?? ;)

Believe me! (believe me!), Believe me! (believe me!), I can't help but love you...but believe me, I'll never let you down!! (okay...who can name that song?? hint: it's Elvis, and it's from the same era/album I just alluded to)

Blog on (and hopefully, with pictures next time, cutting to the chase, sans-narration...here I go again!)

---JL