Good sound and all you need
This article will help you choose the equipment that best suits your tasks. Here we will try to talk not so much about HOW these or those devices are arranged, but about WHAT they do with sound.
The output voltage of microphones is usually unity, at best tens of millivolts. This signal is very weak, and its quality when transmitting over long cables is greatly deteriorated, not to mention the practical impossibility of connecting one microphone to several consoles and getting good sound at the same time.
Now imagine a situation: you need to voice a concert at a stadium or in a sports palace (with a multi-cable 50-100 m long (!), And even artists require a separate monitor) … A nightmare! How to be
In this situation, only the use of separate (rack) microphone preamps can save you. These devices, manufactured by a number of companies under various names, have, as a rule, the structural diagram shown in the figure. It should be noted that this is one of the most complete structures: many companies produce preamps with a much smaller set of functions.
After the normalizing input stages are pre-processing devices. The most common ones are: a filter for trimming unwanted low-frequency components (3) and a phase inverter (4) for phasing microphones. After amplification and pre-processing, the signal is fed through the output amplifiers (5) to the output (s). The number of outputs in each channel ranges from 1 (the cheapest, most common option) to 4 (extremely rare, only in exotic models). Output buffer amplifiers, as a rule, have an increased load capacity and can operate on a line with a resistance of 600 ohms.
Get a few separate mic preamps – and you’ll even be surprised at how many problems you got rid of!
In the above nightmare case, instead of “pulling” one WEAK signal with LONG cables on TWO remote controls – you connect the microphone with a SHORT wire to the preamp set on the STAGE – and you get a clear sound that is not “eaten” by long cables. From the stage to the consoles, the signal will go from a powerful output, with a high level – and he will no longer be afraid of any losses and interference in a long cable. The presence of several independent outputs allows you to “distribute” a signal to several consumers and completely eliminate their influence on each other, which is often a problem (when connecting a monitor remote control, television recording, etc.). Result: great sound.
Another wide area of application is sound recording. Recently, more and more often, the recording of the original phonograms is carried out without any correction whatsoever. In this case, it is preferable to record, completely bypassing the mixing console and applying a signal to the tape recorder directly from the outputs of the microphone preamps (direct recording, or “direct recordind”). This significantly reduces the signal path – from the microphone to the recorder – and creates the best conditions for transmitting the finest nuances of sound.
An additional advantage of using separate microphone amplifiers is the ability to use inexpensive “linear” mixing consoles without built-in microphone amplifiers, because to record modern music with an abundance of electronic sounds, it is often enough to have 3-4 microphones, while the remaining microphone inputs are not used in a large expensive remote control and the money for their purchase is wasted.
In some cases, it is possible to do without a remote control at all – as, for example, when recording music using computer sound cards or recording live concerts on DAT, ADAT and other tape recorders.
Equalizers available in most mixing consoles – band and semi-parametric – usually do not provide all the variety of required frequency characteristics, and often there is a need to use external frequency correction devices. In those cases when a deep frequency correction of the source signals is required, in the sound engineering most often a parametric equalizer is used.
In the parametric equalizer for each band, all parameters are independently adjusted (hence the name – “parametric”): the central frequency of regulation fо, the width of the control band and the amount of rise / fall of the frequency response
The narrower the band (the higher the Q factor), the narrower the spectrum can be corrected – for example, you can only accent the moment of the hit of a stick on the plastic of the drum with a stick. Or vice versa – by setting a wide band (low quality factor), you can raise or lower a large part of the spectrum without making special emphasis on one instrument or sound.