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Lecture recording can be defined as the process of capturing the audio and visual components of a lecture, digitizing, storing, and distributing them. There exist two kinds of lecture recording – synchronous and asynchronous. Synchronous recording is when at the time of recording, the lecture is also broadcast live to its audience. Asynchronous recording, on the other hand, when the lecture is recorded, archived, and can only be accessed after the recording has been made.

Two main components make up the lecture recording process – hardware components and software components. The hardware must work in synergy with the software to provide an effective recording and broadcasting service to the audience.

The hardware component consists of the capture equipment, the server/repository, and the viewing equipment. Generally, the capture equipment consists of a microphone input, a video input, and a DVI/VGA frame grabber. Devices, such as the Lecture Recorder, capture these three analog signals, digitize them, and send them over the Internet or LAN to the server or repository. At the server, all three signals are synchronized and produced. Finally, viewers are able to connect to the server (usually via the Internet) and access any of the recordings made.

The software component makes up the software installed on the Lecture Recorder itself, the server, and the viewer’s computers. Modern techniques in OCR (optical character recognition), fast indexing, and video compression allow lecture recording platforms to contain many of the elements found in today’s Web 2.0 environment.

As such, lecture recording, while not completely replacing physical lecture attendance, is becoming a key tool and learning aid with students who need to review a lecture after they have attended it or if they missed it. Lecture Recorders make students’ lives easier, while at the same time creating an archive of all lectures for accountability and educational purposes.

Most music today is recorded on a Digital Audio Workstation (DAW), the heart of which is a computer and recording software. A few of the major players in recording software today are Cubase by Steinberg Media Technology, Protools by Digidesign, Logic by Apple, and Sonar by Cakewalk. There are basically three things you can do with your DAW: record, edit, and mix. This article is focused on the first process, recording or ‘laying down tracks.’

Since it’s easy to be overwhelmed by the myriad features, options, and settings in today’s recording software, I’ll stick to the basics. My examples will use Cubase, since that’s the recording software I use. However, the basic process will be similar with other recording programs.

Begin by installing your audio digital interface and recording software and setting them up to work together. For example: if you are using Cubase, go to the Devices menu, select the Device Setup window, and choose the software driver which came with your interface.

Now hook-up your instrument or microphone(s). Most instruments with audio outputs should plug into the -10 db input on your interface; the interface will then amplify the signal by ten decibels. Microphones will require amplification by a preamp (often abbreviated to pre), a feature built-into many digital audio interfaces. Most microphones will plug into the +4 db input, and the interface will pad or reduce the signal by four decibels.

Next, you’ll setup your first recording project. In Cubase, choose New Project from the File menu. You’ll be asked to specify a location to store your files. Be sure to create a new folder for each new project. Your recording software will then create subfolders as needed. Save your new project. Then set the recording quality for your project, that is the sampling frequency and bit depth. Select Project Setup on the Project menu in Cubase. Keep in mind that CDs use 44.1 kHz and 16 bit. Higher settings improve quality, but also dramatically increase the demand on your computer processor and the size of audio files generated and stored on your hard drive.

If you are familiar with mixing live sound and understand signal flow, you’ve got a great start on this next step. Create a new input bus (use VST Connections in Cubase’s Devices menu). Choose mono configuration for an individual microphone and many instruments or stereo configuration if you’re using two microphones or an instrument with Right and Left outputs. Set this bus to use the appropriate input from your audio digital interface. Now create a new audio track to record on (Add Track on the Cubase Project menu), and assign the input bus you just created to this track.

At this point you may elect to record your track dry, use an external digital signal processor (DSP) to enhance the signal (perhaps with compression, EQ, or reverb) prior to recording, or employ an insert to apply effects within Cubase. Plug-ins are either DSPs or virtual instruments designed to work together with your recording software. VST (Virtual Studio Technology) plug-ins work best with Cubase. Before purchasing plug-ins, check to see what plug-ins come pre-installed with your DAW software and what type(s) are compatible with your software. Cubase, for example, provides plug-ins for compression, EQ, reverb, and a variety of other commonly used effects. While major studios commonly apply compression and EQ to tracks before recording, it’s quite acceptable and often preferable to record your tracks dry, then edit them later taking time to experiment and find just the right effects to enhance your recording. Consult your manual to learn how to insert plug-ins into the signal flow while recording.

As you begin recording, another important concept to understand is signal-to-noise ratio (SNR). Along with the voice or instrument you intend to record, you will virtually always also be recording a certain amount of ambient noise, including both noise from inside the room (such as a computer fan, fluorescent light ballast, or toe-tapping) and outside (such as wind or road noise). Your goal is to maximize the signal-to-noise ratio and thereby minimize unwanted noise to the point where it is undetectable. You do this both by sound isolation and by making your signal as loud and clear as possible without distortion.

Now it’s time to record. Choose the track to which you will be recording, and make sure the correct input is assigned. Enable record or ‘arm the track’ by pushing the red button. Take a look at the meter on the transport panel (or click the monitor button) to make sure the signal is coming through. Use the fader to set the level for maximum SNR without distortion. Finally, press the record button to begin and the stop button to end recording.

That’s not all! Play back your track and listen carefully to how it sounds. Don’t be afraid to record multiple takes until you’re completely satisfied. Even professionals record multiple takes. If fact, before you even record onto your first track, you may want to copy it and create several duplicate tracks to save steps in setting up tracks for multiple takes. You may also want to overdub, recording different sections separately to edit and mix later. For those who use Cubase, I’ve discovered some cool video tutorials on the web at www.maketunes.com/articles/cubase-tutorial-videos.

Happy recording!

Pro Tools

Pro Tools this, and Pro Tools that. Sometimes you would get the impression that Pro Tools is the only way to record great sounding music on your computer but the truth is nothing could be further from the truth. In fact, I think there are other options that are far better.

In this article I focus on one such option for those who use (or who want to us) a Mac computer to record and mix their own music (or who want to record and mix other people’s music, of course.)

Logic Studio

The amount of features that Logic has in comparison to the competition (including that aforementioned) is truly impressive.

I do not think there’s a more intuitive way to record your own music with all of the top of the line features that you will want to make professional sounding mixes.

And I’m quite sure there is no software in it’s class that has as many features. To get an idea of what I’m talking about I will list some of it’s features below.

Logic Studio Features

• Royalty free loops in all kinds of styles. These can be a great way to get started creating a new song.
• Templates. There are different templates for different types of projects. Using these templates can save you a lot of time when you’re getting started.
• Creates music notation based on your music.
• Surround sound mixing capabilities.
• Low Latency Mode can help to fix latency issues. This can save a lot of headaches.
• Easily create a new sampler based on any part of your music.
• It’s shipped with lots of plugins so you won’t have to spend a bunch of time looking for plugins instead of recording your music.

Compression

When I first started reading about compressors I was hopelessly lost. The terminology was technical in an almost mean-spirited way and I couldn’t make heads or tails of what was being written. To keep things simple, I think of compression as a way of evening out the loud and soft parts of any vocal or instrument so that its behavior is a bit more predictable. In other words, compression brings up the really soft spots and tames the really loud spots so that you’re not constantly reaching for the volume fader on your mixing board (or virtual mixing board on your DAW). In its simplest form, a compressor, whether a hardware unit or a plug-in, will squeeze the audio so that its highs and lows are less pronounced. This allows you to do things like bring down the volume level of the compressed track without fear that its softer parts will get lost, or bring up the volume level without fear that the loud parts will jump out. It might help to think of all compression settings (attack, release, ratio and threshold) as ways to squeeze your audio more or less aggressively. Not enough compression will leave tracks that jump out of a mix at inappropriate times or get lost in the sound of the other instruments; however, too much compression can make a track sound lifeless or uninspired. My rule of thumb is to be less aggressive compressing audio on the way into your DAW (because you’re stuck with whatever you do) and more aggressive with my plug-in compression (because you can always dial it back).

EQ

While a wonderful (and essential) tool, EQ is also quite possibly the quickest way to royally mess up the sound of a mix. Overuse of EQ ranks second only to overuse of reverb as the hallmark of an inexperienced mix engineer. EQ should be used to subtly (or not so subtly) color the sound of the particular track you’re working on so that it relates well to and leaves space for the other tracks in a mix. My experience has been that it’s what you pull out and not what you put in that makes EQ work best. For example, even when you’re looking for a boost in the high frequencies of a track, it’s often more effective to pull a few dB from a lower frequency which, in turn, brightens the sound.

Vocals Vocal Compression on the Way In

Since the vocal (despite what your guitar-playing pals might tell you) is the most important element of any popular music mix, let’s start here. Getting a vocal to sit well in a mix is a combination of compression, EQ and often volume fader automation. It’s a fairly common practice to compress a vocal a little on its way into your DAW. This shouldn’t be an aggressive type of compression but rather just enough to tame some of the loudest spots of a vocal so that your overall recording volume can be hotter.

An approach to the vocal chain in my studio runs as follows: microphone into hardware preamp/compressor and then directly into my DAW. To get into the nitty gritty, I generally set my hardware compressor’s attack settings at around 30ms and release settings at about 1 second and my compression ratio to 3:1. Then, I play with the threshold making sure that at the hottest parts of the vocal, the gain reduction is at a maximum of -3dB. This leaves me room in the mix to compress further using a software compression plug-in. The danger of compressing too aggressively on the way in is that you’ll end up stuck with the sound of the overly compressed vocal with no way of changing it later.

Vocal Compression in the Mix

Once the vocal is in the mix, I go to a plug-in compressor to further help keep the vocal present in the mix without jumping out too much in the loud spots. My recommendation would be to find a compressor that has a smooth, transparent sound that allows you to squeeze the vocal just a little more (approximately -3dB of gain reduction at the loudest spots) so that the vocal maintains it’s presence. I set my attack at 26ms and my release at around 300ms. For more detail, take a peek at my general vocal settings in the screen shots on the right. If the mix is a particularly full one where the voice needs to cut through a bit more and show a little more sparkle, I’ll use a frequency-specific compressor (like the Waves C4 on its “pop vocal” setting) which is a little more specific in terms of which frequencies it chooses to compress. In this case, 40hz, 500hz, 6khz and 16khz. To see exactly how the attack and release settings are set up for each frequency, take a look at the screen shot here below.

Vocal EQ

I rarely, if ever, EQ my vocals on the way in. I prefer to get a good uncolored vocal sound so that when it comes time to mix with the final instrumentation, I have the flexibility to work with the un-EQed vocal audio. This is particularly useful when you start by tracking a vocal against a single instrument like the acoustic guitar but end up mixing it in with a full band. EQ decisions shouldn’t be made in a vacuum. Ultimately it’s the relationship of the voice with all of the other elements in the mix that determines the EQ approach. Often, a vocal EQ that works in a mix won’t sound particularly good when the vocal is soloed. As I mentioned earlier, my preference is to cut the EQ in certain frequencies as opposed to boosting it.

Here are a couple of instances where cutting frequencies can solve common vocal problems:

• Muddy or Boomy Vocal – In this situation, I tend to pull a dB or two at around 200hz. This also has the effect of making the vocal cut through a mix better or sound brighter.
• Piercing or Painful Vocal – Here, I’ll pull a few dB at around 3 khz. This tends to take the edge off of the vocal without removing any of the clarity.

Here are a couple of instances where the tasteful boosting of frequencies is useful:

• Bringing out the low end in a vocal – add 1 or 2db of gain at between 80hz and 100hz
• Adding Brightness – Occasionally if a vocal sound is just a bit too dark or undefined, I’ll add a few dB of gain at 5khz
• Adding Air or Breath – Here I’ll use a shelving EQ which boosts all frequencies above 12.5khz

Shelving

In a shelving EQ, a band of frequencies, in either the high or low frequency end of the spectrum, is increased or attenuated by a fixed amount. The term shelving doesn’t usually apply to a mid-range boost or cut.

Acoustic Guitars

While working as an engineer in Nashville, I spent a lot of time miking and recording acoustic guitars. Despite the steadily improving pickup systems being installed in acoustic guitars, I still believe that there is no substitute for a well-placed condenser microphone (or microphones) when it comes to capturing the warmth, body and air of an acoustic guitar. However, as with all acoustic instruments, it’s a challenge to properly sit one in a mix and preserve its texture and character while also blending it with the other instruments. There are a couple of approaches to compression and EQ that will go a long way towards solving this problem.

Acoustic Guitar Compression on the Way In

When compressing acoustic guitar on the way into my DAW, I find it’s better to be a bit more aggressive with attack and release settings than you would with a lead vocal. I’ll use the more of a medium fast attack (approximately 22ms) and release (approximately 500ms) on a hardware compressor with a ratio of 3:1 and then play with the threshold knob until, again, the gain is attenuated by about -3dB.

Acoustic Guitar Compression in the Mix

At this point, it’s a good idea to base your compression settings on the kind of a mix you’re doing. If it’s a simple acoustic guitar and vocal recording, it’s entirely possible to leave off all compression on the acoustic. However, if it’s a full band mix and I want to make sure you can hear the acoustic strumming or finger picking clearly among the other instruments, I’ll use a compression plug-in (like Metric Halo’s Channel Strip) and compress a bit more aggressively: 16ms attack and 160ms release with a ration of 3.5:1. Take a peek at my settings.

Ratio

A compressor reduces an audio signal’s gain (level) if its amplitude exceeds a certain threshold. The amount of gain reduction is determined by a ratio. For example, with a ratio of 4:1, when the input level is 4dB higher than the threshold, the the compressor will process the signal so that the output signal level will be 1dB over the threshold. So the gain (level) has been reduced by 3 dB.

Acoustic Guitar EQ

Very much like vocals, I don’t believe in EQing acoustic guitar while I’m recording it, only because I rarely know what the other elements of the mix will be. However, there are a two very specific approaches I use to EQing an acoustic guitar depending on whether or not it’s accompanying a vocal performance or a part of a bigger mix. In general terms, the EQ approach is more subtle in the simple guitar/vocal to preserve the fuller tone of the acoustic and more aggressive in the full-band mix to make room for other instruments while still preserving the essential elements of the acoustic’s sound.

Here are some EQ settings for a simple acoustic guitar and vocal recording:

• Removing Boominess – I like to pull 1 or 2 dB at 125hz to remove the boominess that often accompanies miking an acoustic too close to the sound hole.
• Adding Sparkle – If after removing some of the boominess, I’m still looking for more sparkle in the acoustic, I’ll boost a dB or two at 5khz.

Below are some EQ settings for an acoustic in a full band recording:

• Adding Clarity – I’ve found that a high-pass filter at 120hz leaves room for the kick drum and bass guitar in a mix while allowing the acoustic to shine at the higher frequencies. Leaving in the low parts of the acoustic’s frequency will often muddy the mix and obscure the kick drum and bass.
• Still muddy? – don’t be afraid to take your high-pass filter up to 200hz or even 300hz if the guitar still isn’t cutting through the mix. It may sound terrible soloed but perfect in the mix and that’s the key.
• Adding Sparkle – As above, if cutting out the low frequencies isn’t enough to get the acoustic to cut through a mix, adding two or three dB at 5k will do a lot to bring out the strummed or finger picked strings of the acoustic.

Compression and EQ are two very powerful weapons in your mix arsenal, but as with anything, overuse will do more harm than good. I think back to the words of an engineer whose work I really respect who liked to say “I’ll compress until it sucks and then back it off from there.” In other words, knowing when to say “when” is an equally useful skill. A final thought…as far as signal path is concerned, I tend to place compression after EQ because EQ effectively raises or lowers the volume of the track and I’ve found I get a more effective response from the compressor if I hit it with the EQed audio. I would highly recommend using the above EQ and compression settings not as an ironclad rule but rather as a jumping off point. Every mix is different and your ears will tell you what’s working and what isn’t.

Good luck!