An Audiophiles Challenge (Can You Hear me now?)

So we've explained the pitfalls and challenges of dealing with video images and what works and why.

Now we're going to tackle audio problems and challenges - a subject particularly near and dear to our audio engineer savant Eric Graf:

Yes, we are called Video Resources, but we "do audio" too. If you have an audio recording that needs to be clarified, we’re just the guys that you ought to bring it to. I’d like to tell you what to expect from us, and what you can do to make sure we can give you the results you want.

When dealing with an audio recording that’s hard to understand, the objective is to understand it. It’s not to make the thing a high- fidelity, professional-sounding recording, and usually that’s not possible anyway. Once we get it to where you can understand the conversation, we stop messing with it.

Often we will not be able to snag every word. 60% comprehensible is considered a big improvement over 10%.

If you read my lengthy tome about video, you no doubt remember my rant about the shenanigans on TV shows like CSI. It goes for audio too. To summarize: Much of the “technology” on those shows is more James Bond than LAPD. Do not judge a “real” clarification job by what you hear on those shows. Because frankly, they’re full of it.

What we CAN usually do is reduce background noise, background talking, foreground talking (sometimes), distortion, muffledness, and general unintelligibility. It really depends on a lot of factors.

Sometimes we can work wonders. Occasionally we can't work anything.

But we do have the tools and the expertise to do as much as can be done. Our microcassette player alone retails for $8000, and we often find that it delivers a huge improvement just because it plays so much better than everybody else's microcassette player.

Sometimes we’ll listen to a recording you’ve submitted and say “sorry, we can’t help you.” We like a good challenge, and we like making money while tackling a good challenge, but we aren’t going to waste your time or resources on a lost cause. Here’s how you can help reduce your chances of your cause being lost:

GET US THE ORIGINAL. PLEASE. WE BEG YOU.

You’re probably going to develop a case of déjà vu if you already read the video thing, because the advice is pretty similar. The reasons here are a little different because of the different technology, but overall it’s pretty much the same thing. When you make a copy, you lose quality.

In the case of analog audio, going from tape to tape invariably results in loss of high frequencies and the addition of additional noise. You’re also at the mercy of the copyist, and their ability, or lack thereof, to properly operate the equipment. It’s easier to really screw up audio than it is with video.

There’s also the issue of azimuth adjustment. It’s absolutely vital to the proper reproduction or duplication of any analog audio tape, and if you don’t know what it is, then you’d better just let us handle it. (I’ll be glad to explain it to you, but this would be a REALLY long document if I tried to do it here.)

Digital is a little different. If your audio is an MP3 or a CD, copying the file or the disc itself won’t do any damage whatsoever. Where you get in trouble is when you try to convert it to something other than it was originally. If it was recorded in CD quality, don’t make an MP3 or a WMA of it. When you go from one file type to another, you usually lose some quality that we really need to optimally do our work.

Yeah, we know, sometimes you just can’t get the original to us. OK then, here’s what to keep in mind when making your (shudder) copy:

DON’T copy from microcassette to microcassette. Come to think of it, don’t copy from ANYTHING to microcassette. It’s a low-quality format, and the last thing we need is a second pass through it. Furthermore, most microcassette decks do not have a proper line level input, and if you try to go in through the machine’s microphone jack without attenuation, you’re going to get something absolutely useless that we can't fix (we know because we keep getting asked to). If you have a microcassette to copy, either copy it to full-sized cassette or a CD quality digital file.

DO make a CD-quality audio file (or an actual CD). If you do it right, with decent quality equipment, the quality loss is so minimal that it won’t matter to us. Some caveats: MP3 is NOT CD-quality, no matter what the RIAA’s lawyers say. Many common computer sound cards are not considered “decent-quality equipment.” And if you haven’t adjusted that playback azimuth (which usually involves screwdrivers and removing pieces of your tape deck), you’re losing audio quality that we can’t recover.

Take care of and test your equipment! Does your microcassette make crunching noises while it’s running? STOP USING IT and get it fixed. Do your recordings come out distorted and nasty? Read the cotton pickin’ manual and find out what you’re doing wrong. Do your tapes come out sounding muddy? The machine is probably overdue for an internal cleaning (which means it’s probably also overdue for eating a tape or two). Hand it off to some tech guys and tell them to get scrubbin’.

If you’re using standard-size audio cassettes, be sure you’re using the proper kind for your equipment. There are two types of blank cassette on the market now – Type I and Type II. It’ll be written in teeny type somewhere on the tape box. Type II is more expensive, but it’s mainly for recording music on home stereo systems, and will actually perform noticeably worse in most portable equipment. Type I is the safe choice, and will work great if you buy the quality stuff. Buy only name brands (TDK, Maxell, Sony are good). Try to avoid tape lengths longer than 90 minutes. The 120-minute tapes are trouble-prone and don’t record as well.

Next Blog We'll cover the  ups and downs of DIGITAL RECORDERS

The "Digital Quality Myth" (Say it ain't so!)

OK - in the previous blogisode my sidekick and ally in presentations Eric Graf exploded many of the make-believe antics that pass for science on those pop cop "CSI" - type soap operas that have the masses convinced that such visual alchemy truly exists.

One of the culprits that I feel has encouraged the feebs who write the CSI tripe is the DVR, or Digital Video Recorder. I've personally witnessed the growth of these machines over the past 5 or 6 years in the surveillance arena and have marveled at the promises made by the manufacturers that hawk them to their unsuspecting customers with the overt promise of the unit being capable of isolating an incident (and any suspect within the incident) and then enlarge said subjects facial features for police identification.

I've had the sad chore of bursting many a security manager's bubble when I point out the REAL limitations of their 32 camera, state of the art, real-time, internet accessable system. I no longer feel the need to let them rest their head on my shoulder anymore while gently rocking them and saying "There, there, it wasn't your fault".

Because, it is their fault. They should know better.

Here's why - Here's Eric's take on what we'll call "The Digital Myth":

DIGITAL IS NOT NECESSARILY BETTER  (Regardless of what you've been told)
 
Actually, I could almost leave out the “necessarily.”  There’s this dirty secret about digital video that they don’t tell you.  Here it is.  Y’ready?
 
To save space, digital video throws out details of the picture that it doesn’t think you’ll miss.
 
It’s really obvious on some internet videos, where you’ll see people’s faces disappear into a detail-less blob.  Trouble is, nearly all digital video, including DVD, DV tape, TiVO, high-definition broadcast, and (especially) surveillance systems, does the same thing to a certain extent, and it messes up our ability to do some of the cool CSI things we actually can do.
 
DVDs are particularly bad about this, particularly if you’re using a consumer-grade recorder, and PARTICULARLY if the original source is VHS.  VHS has a lot of extraneous "noise" in the picture, and extraneous noise tends to confuse DVD recorders into throwing out more of the important details than they ordinarily would.
 
Going from analog to digital also has some hazards not directly related to the nature of digital.  For instance, every consumer grade DVD recorder we have ever tested, without exception, records the video black level incorrectly.  It’s a long story as to why (and if you feel you MUST hear it, you can email me), but the point is that it’s a problem for us, and there’s not a darn thing you can do about it without professional video equipment.  (Side note . . . many DV recorders and computer video cards do the same thing.)  It’s best to send us the original, and if there are DVDs to be made, let us make them.
 
Copying digitally (through Firewire) from DV tape to DVD usually goes better, but there’s still quality loss, especially in the color information, because DVD ditches a lot more of the detail info than DV tape does.
 
YOUR SHINY NEW DIGITAL SURVEILLANCE RECORDER  (It's not what you thought it was)
 
OK, if you have one of these newfangled gizmos, pay very close attention!

Guess how they manage to get a month’s worth of video onto a single hard drive?
 
That’s right.  They toss out everything, even the kitchen sink.  And they record the picture at a horrible resolution setting that guarantees that anything smaller than a Peterbilt won’t be recognizable.
 
If you have your digital device set to record at the maximum time setting, you might as well not waste your electricity.  You will not get ANYTHING useful.  Period.  End of story.  We have a lot of would-be clients who learned this the hard way.  And sadly, most of the salespeople who handle these things don’t bother telling you this, figuring that you’ll assume (incorrectly) that somebody like us will be able to bail you out when the need arises.
 
Change those settings now!   

Go for the shortest time period and the highest quality you can possibly get away with.  Use your own eyeballs and your own common sense.  As already discussed, video does not enlarge well, so if you can’t see it on your screen, there’s a good chance we won’t be able see it on ours either. 
 
If you have everything maxed out and still can’t see stuff, consider rethinking the position and coverage of the cameras.  Yes, you might miss something if you’re zoomed in too tight, but you’ll miss EVERYTHING if you’re zoomed out too wide.  A teeny little blurry picture of a teeny little blurry guy stealing your Bentley isn’t going to help you or the cops or us or the Bentley.  If you’re worried about the Bentley, then zoom in on the Bentley!  Let the Yugo parked next to it fend for itself.

Stay Tuned.. Our next blogisode will have you questioning everything you believed you knew about AUDIO!