Using Microphone Preamps
Before you can record the signal from a microphone, the signal must be audible. That requires amplification from what’s known as a microphone preamp, or mic pre. Mic pres come in many varieties. Some are found on sound cards. Some are external devices that work alongside sound cards. Most audio mixers have gain knobs that can be considered mic pres. Their most basic functionality is to boost the signal of the mic, but they work in different ways. The largest difference is in technology. The two main choices are solid-state mic pres and tube mic pres. Solid-state mic pres deliver a very clean and accurate representation of the audio. A good tube mic pre can offer a more vintage, or warm, edge to a recording. Both types have been around for a long time, but every manufacturer has its own take on what makes a good solid-state or tube mic pre. This means that your choice of mic pre is another ingredient in the sound you want to create and can make or break the vocal recording almost as much as the microphone itself.
Some sound cards, such as the M-Audio Fast Track Pro (see Figure 5.4), come with built-in mic pres, very handy for those who just require a simple microphone connection to a computer.
Figure 5.4. The M-Audio Fast Track Pro with built-in dual mic pres.
For those who want to take their vocal experience to higher levels, you can get external units that offer not only premium microphone pream-plification but also audio compression and equalization. An example of such a device is the Avalon VT-737SP (see Figure 5.5).
Figure 5.5. The Avalon VT-737SP mic pre also offers compression and equalization.
Even though Cubase can handle equalization and compression, these steps are often completed before the signal is converted from an analog to digital to ensure the best SNR. If you’re looking for the secret to most major record producers’ full vocal sound, it’s mostly in the microphone, the mic pre, the compression, and the EQ, and it’s all done before the sound even reaches the computer. Of course, you also need to know how to use this equipment. The same principles for using Cubase’s internal plug-in compressors and EQ can be applied to the external processors, and I will go over these a little later in this chapter.
Mic pres usually have at least one control, the gain control, for the loudness of the microphone. Fancier mic pres have a loudness level indicator (the meter), which helps in selecting proper gain settings. The professional choice in meters is a VU meter (see Figure 5.6). It may look a little old-fashioned compared to the flashier LED meters available on other makes, but VU is a favorite because of its speed and accuracy in determining audio signal peaks.
Figure 5.6. VU meters, popular for their efficiency in determining audio signal peaks, are commonly found on mic pres.
Note
When using any type of external meter to determine audio levels, it’s always good to make sure the signal peaks in the red. However, if a signal is in the red a majority of the time, you will probably end up with distortion. If the signal is too far below the red, however, you may have too much ambient noise. A vocal recording can have a wide range of dynamics in any take; make sure you use a gain setting that works for both the loudest and softest points of a performance.