Studio Closed Project Studio Spaces for Rent Sorcerer Sound has ceased studio operations. The space has been divided up into a number of rooms which are available for rent as Project Studio spaces.Call us at 212-226-0480 or visit our Rental Page for more info. We still have some gear to sell including vintage Neve Modules plus a huge quantity of parts and manuals for sale. See our sale pages for more information. Our parent company, Acoustilog, Inc. will continue to provide acoustic consultation services to the recording industry as well as commercial and residential clients.

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Articles

• Compressors and Limiters
• Gates
• Don't Be A Victim Of Schlock Rock

Why then would we want to do this? Sometimes the Dynamic Range³ of a signal is greater than we would like. Radio broadcast provides a good example. The CD's they play may have a Dynamic Range of 40 dB or more for some Classical Music. In a very quiet room, with a sound system capable of high volume levels, the listener might be able to hear the full dynamic range of the music. But of course this is not the typical case. The "sound system" is quite likely a portable radio or home stereo and the "listening room" may even be an automobile! In order for the listener to hear the soft passages at all over the background noise, the loudest passages would have to be uncomfortably loud, and would likely exceed the capacity of the sound system. To remedy this situation all radio stations use compression on their broadcasts. In fact, they use a great deal of compression, squashing the dynamic range down to a very small amount.

In a similar fashion, some components of recorded music may have too great a dynamic range to fit into the mix in a useful way. Vocals are a good example. The singer, for reasons of pitch, skill or style, will typically produce a wide range of loudness variation. Left unchanged, this can present a problem. If we set the level of the vocal such that the softest parts can be adequately heard in the mix, the loudest parts will probably be too loud. If we lower the vocal so that the loud sections sound correct, the soft sections may disappear altogether.

We could attempt to remedy this situation by manual "gain riding", i.e. moving the fader⁴ up and down to compensate for the vocal track's excess dynamic range. This method can work, but has two distinct disadvantages. Firstly, it's a big pain in the neck, especially if there are many moves to make. This may become impossible if there are several tracks that need this treatment.

Secondly, in some cases the track may need many gain changes in quick succession ; too many, too quickly for human hands to perform. In the case of a vocal track, several changes might be required in the space of one word. It's usually better to let a compressor take care of this problem and save the console fader for longer term level changes.

Footnotes: Click here to return to the top of this article

1. A limiter is a special case of a compressor.For convenience, we will refer to compressors only in the beginning of this article.
2. Usually a VCA (Voltage Controlled Amplifier)
3. Dynamic Range: The difference in level between the softest and loudest parts of a signal. Expressed in decibels (dB)
4. Fader: A volume control, typically found on a mixer or console. Usually linear

Why would you want to do this? The first answer is to remove unwanted signals and noise. An example: If you solo¹ any vocal track and turn it up pretty loud, you'll probably hear the music tracks leaking through. You might think it's crosstalk² , but it's more likely to be headphone leakage. This occurs because headphones don't seal perfectly to the performer's head. They let some sound escape, which is picked up by the microphone. This leakage can become a problem if you have an "a cappella" section in your mix, or anyplace where you drop out the drums. A gate can help. You can set the gate such that it will allow loud signals (the vocal) to pass, but cut off soft signals (the headphone leakage), leaving you with a nice clean track.

Another common noise problem is guitar amp hum and buzz. You can set the gate to "open" (turn on) when notes are played, but close (turn off) in between notes cutting off the hum. In each case the principle is as follows: When the instrument is playing, it covers up the noise. But in between notes or words, we can hear leakage and noise. In those "in between" times we can use a gate to silence the noise.

It is important to note that a gate cannot perform miracles. It can only differentiate between the signals we want and the ones we don't by level (and sometimes frequency range). This means you have to record as cleanly as possible in the first place. If the guitar hum is nearly as loud as the guitar, gating may not be adequate to fix the problem.

A second reason to use a gate is to change the sound of an instrument, particularly drums and percussion. Sometimes a drum "rings" longer than we would like. You can set a gate to cut off the end of the drum sound to make it "tighter".

CONTROLS:

Play the signal though the gate. Adjust the threshold until it reliably cuts off what you don't want but leaves all of what you do want. This may take several passes to fine tune it. Many gates also have LED's⁴ as a visual aid.

If a gate was really just a switch, fully on, or fully off, with no intermediate levels, it wouldn't be very useful. It would cut off unnaturally, usually with a "click". In most cases we don't want the listener to notice the action of the gate. We want them to hear clean sound, as if there was never any noise to begin with.

To accomplish this, most gates have "envelope" controls: Attack Time, Release Time and (sometimes) Hold. Instead of opening immediately when the signal exceeds the threshold, the gate ramps up. It is as if someone turned up a volume knob very quickly instead of turning on a switch. This prevents a turn-on click. The rate at which it ramps up is set with the Attack Time control.

Similarly, when the signal drops below the threshold, the gate ramps down instead of cutting off immediately. This rate is set with the Release Time⁵ control. The release time control has much longer settings than the attack time control, up to a few seconds. This is because we almost always want the gate to open very quickly, but sometimes we want it to close slowly. You'll find that gating vocals may require a longer release time to prevent the vocals from sounding unnatural. As a rule of thumb, short release times cut off the most noise, but make the operation of the gate more noticeable. Longer release times allow more noise through but may sound less annoying on vocals and other non-percussive sounds.

The Hold control is only found on some more expensive gates. When the signal drops below the threshold it will hold the gate at full level for the set amount of time before it begins it's ramp down.

Most gates also have Input Level and Output Level controls. It is important to remember that these are used to set the operating levels in the device rather than to make artistic decisions. This is the case with most outboard gear. Many people have their level controls set in crazy random ways. When they want something louder or softer they just grab any control that will do it. This can lead to some devices operating at the wrong levels, resulting in distortion or added noise. Try to set each device to it's proper levels and then use your Mixer to set the sound balance the way you like it. Many gates and other outboard gear have simple level meters or at least clip lights⁶ to help you set the levels correctly.

Some more expensive gates also have Detection Filter controls. These allow you to zero in on just the frequency range you are interested in. Take the guitar hum example. Suppose the hum is very loud and there's nothing you can do to reduce it. It might be difficult to set the gate to cut off the hum without cutting off some of the notes since the hum is close in level to the guitar sound. You could set the detection filter to ignore the low frequencies (the hum) and only listen to mid-frequencies (the guitar notes). It is important to note that the filter doesn't act as an equalizer for the signal you hear, it only changes the signal that is sent to the detection circuitry inside the unit. Thus it won't change the tonal balance of the sound you hear.

What if you don't have Detection Filters on your unit? Most gates have an External Input jack that allows you to do the same thing. This allows you to send one signal to the control circuitry and another through the regular audio path. This is how you can use this feature to imitate Detection Filters: Send the guitar signal through an equalizer. EQ it so you cut off as much hum as possible, and accentuate the guitar. Don't worry if the guitar sound is ruined in the process, you won't be hearing this sound in the mix. Send this signal into the External Input of the gate. Then send the un-EQ'd guitar signal to the gate's Main Input. If you don't have a patch bay you may need a Y-cord to send the guitar signal to two places. Set the gate to "External Input" and adjust the other controls in the usual way. Since the gate is "listening" to the severely EQ'd signal from the External Input it will "hear" the hum as being much lower in level than it really is. This will allow it to better differentiate between the guitar and the hum. You can use this method any time you have unwanted sound that differs in frequency range from the sound you do want.

The External Input can also be used for special effects. Suppose that instead of putting an EQ'd version of the same instrument into the external input, you use some other instrument altogether? If you have Strings in the Main Input and Hi-Hat in the External In, the Strings will "pulsate" to the beat of the Hi-Hat!

Lastly, most gates have a Range Control. This sets how much the signal will be attenuated when the gate is closed. Usually this is set to infinity , thus totally turning off the sound. But it can be set instead to merely lower the sound level by a set amount. This is particularly useful when you are trying to change the sound of an instrument, not cut off unwanted sounds.

Gates can do a great deal more than most people use them for. Take some time to experiment with the controls, preferably when you're not working under a deadline. Maybe you'll invent some studio tricks no one else has even thought of!

Footnotes: Click here to return to the top of this article

1. Solo: A button on many mixers that allows you to listen to one channel alone.
2. Crosstalk: Electronic signal "leakage" from one track or channel to another.
3. Some gates have this backwards, with the lowest threshold at the full-clockwise position of the knob
4. LED's: Light-Emitting-Diodes (Lights)
5. This is sometimes called "Decay Time" instead.
6. Clip Lights: These come on when the signal level is high enough to cause distortion. But remember: Use your EARS! No clip light is perfect

Wrong!

Most people don't realize how risky it is to trust a valuable master tape, with all that went into it, to the ravages of a cheap studio.

Let me count the ways:

1. Tape heads which are slightly magnetized will wear out the highs on your tape. Tape heads that aren't lapped correctly will scrape oxide off. Guides that aren't set up properly will damage the edges of your tape, making future playbacks unsteady, even on a perfect machine.

2. You're going to be printing less-than-perfect overdubs unless their machine is aligned correctly. Many studios use an alignment tape which is several years old, or don't know how to correctly align their machine to your tones. There are times that you shouldn't use the project tones for alignment, but very few studios know this. Do they have peak meters, like they should, and are they calibrated properly? Most don't, and they're not. By definition, an overdub is a track that you're singling out to spend specific time on, so it must be important. Do you care that your overdubs are of good quality?

3. Are the acoustics of the control room set up to accurately monitor your project? In most small studios, probably not. For one thing, if they only have small speakers, there is no accurate bass. Yamaha NS-10's have a peak at 125 Hertz, with very little low bass. If your song is in one key, it might sound bassy, but in another key it will be thin. Which is right? Small speakers are not sufficient, even for overdubs. If you think that your own near-fields will sound the same in all rooms, you're dead wrong. The shape of the meter bridge on each console affects the sound differently. You need to have large speakers, tuned properly, in an accurately designed room. The way your overdubs blend with the music also depends on the monitoring system.

4. Hum and RF (radio frequencies), even distortion, cannot be heard as well on bad speakers. Your overdubs may have problems and you won't even know it 'til you mix. Then they may have to be redone. I was in a studio recently that had low-level radio stations on their only mike for the last 2 years and they thought there was no answer. They just lived with it and kept the volume down.

5. Spectrum analyzers are expensive, but they make equalizing your sound much easier and more accurate. A small studio may offer you a lower rate, but if it takes longer to get the sound how much are you really saving?

6. Are the mikes in phase? Are the cables checked regularly? Do they have a console with worn-out parts that are messing up the sound? Do they have an older machine with a questionable alignment? Is the balanced and unbalanced, low-level and hi-level, low impedance and high impedance equipment interfaced properly? Is old tube equipment properly set up? All of these things are almost impossible for you to see.

Here's How To Save Money On Overdubs, The Smart Way

1. Plan your overdubs at home, using a rough mix from the previous session. Use as little effects as possible.

2. Plan several short overdub sessions rather than one long one. You can critique your work better if there's only one instrument to concentrate on.

3. If you only do guitar overdubs in a session, its easier to be "on-call" with your guitarist. Therefore, ask the studio if they offer "on-call" or "bumpable" time at a discount.

4. Overdub "parties" aren't very efficient. Only invite the key people.

5. Go to a studio with a reputation for technical quality, with an accurate monitoring system that's tuned regularly, with a real shop staffed with technicians who know what they're doing.

The brand new studio may look flashy, but they have years of bugs to work out. You may be their guinea pig. Experience is safety. So remember, "fixing it in the mix" takes four times as long as doing it right the first time. Copyright 1991 Alan Fierstein, Acoustilog, Inc.