The sound signals coming out of a mix are of low amplitude. That's why the loudness is low, and you won't be able to hear the words. This is where mic preamps come to the rescue. It's a sound amplifier that will increase the signal amplitude, reduce noise distortions, introduce clarity and sharpness in the sounds, and increase the energy.
Since the amplifiers are so beneficial, they are used whenever a mic is used to generate output signal waves. Concerts, live shows, DJ shows, and other programs need this device to amplify sound energy and loudness. However, choosing the best mic preamp is not everyone's forte. That’s why we have created a well-explained buying guide to help you pick the best product for your purpose.
How Does A Mic Preamp Work?
When a sound signal is given at the input channel of the preamp from a microphone, it is fed to an amplifier circuit. A gain box is present in the amplifier circuit, which adds a value to the amplitude, thereby increasing it to a certain level as per the gain factor. The output sound signal will be similar to the input signal, with the only difference being amplitude. In some preamplifiers, a feedback channel is connected with the amplifier circuit. A part of the output signal is fed to the input to maintain the signal quality and gain stability.
What Are The Different Types Of Mic Preamps?
The microphone preamplifiers can be categorized into three groups based on the amplification process. In this section, we will introduce you to the three amplifier types available in the market.
Tube Mic Preamps
Inside these devices, a long hollow tube is present with a vacuum inside. The sound waves travel through the tube, and due to repeated reflection, their amplitudes increase a lot. However, as no filter is present in these preamps, the output sound signals might have superimposed noises, thereby causing distortions.
Transistor-Based Preamps
Transistors replaced the vacuum tubes used for amplifying the sounds in the mic preamps. These are solid-state devices that increase the amplitudes of the sound waves and reduce noise distortions. Moreover, with the evolution in electronics technology, the mic preamps are now made from different transistors for amplifying the sound waves accurately.
IC-Based Mic Amplifiers
These are modern preamps connected with the microphones where you will find the main technology to be the IC or Integrated Circuit boards. They are made from small solid-state devices like transistors, OP AMPS, filters, and others. Due to the reduced size of the circuit components, the amplifiers have a compact design.
What Factors Should You Consider For Choosing The Best Mic Preamp?
Number Of Channels
The first factor that you need to consider for buying the best preamp is the total number of channels present in the preamp. These channels signify the number of lines through which the audio signals will pass. Based on the channel numbers, you can divide the preamps into three forms — a single-channel amplifier, a dual-channel amplifier, and a multichannel amplifier. A mono channel amplifier can be connected with a single output device while the dual-channel preamps allow you to control two different output systems. If you want to control several sound systems with a single amplifier, make sure that it has multiple output channels.
Input/Output Connections
Secondly, you have to think about the total connection ports and their types present in the amplifier. No matter which technology you choose for the preamp, there should be one input coming from the mic and one output that will connect the amplifier to the speaker. In the latest IC amplifiers, several input and output ports are integrated to ensure that you can receive inputs from different sources and sample the output signal to different devices.
Filters
In the basic preamps, no filter circuit is available. As a result, distortions can be easily superimposed on the harmonics, which will result in poor-quality sound signals. However, most modern preamps are reinforced with in-built filters that can remove the distorted signals and noise, thereby maintaining the signal quality.
Balancer And Equalizer
If you want to get an amplifier with some additional features, you can look for the models with an in-built load balancer and equalizer. A load balancer will allow you to ensure that the signals in all the channels have equivalent gain or amplification. Besides, an equalizer will prevent unwanted gains in the sound signals, thereby equalizing the output and helping in the reproduction of the input signals perfectly.
Purpose
Lastly, it would be best if you chose the microphone preamp based on the purpose. For normal studio works, you can select the transistor-based or tube-based amplifiers, which are cheaper than the IC-based amplifier. However, suppose you want to use the amplifier for live shows and concerts. In that case, the IC amplifiers are best as they provide fast amplification and come with several other features that will help generate sound waves without any signal distortion.
What Are The Applications Of A Mic Preamp?
A microphone preamplifier can be used in several ways for increasing the amplitude of the sound waves and the loudness. Starting from recording studios to live concerts, a preamp is used whenever one needs to amplify the signals for sound clarity, reduce noise distortion, enhance gain stability, and increase loudness.
Mic Preamp FAQ
Q. Which type of microphone preamplifier should I choose for a live DJ show?
A. For live shows, you need quick amplification with minimal signal distortion. That's why it will be best to choose the IC-based preamps. These are the most advanced forms of amplifiers where you will be able to use several features to amplify and balance the sound signals and reproduce the exact wave forms without any distortion.
Q. Do I need a channel strip along with a preamp?
A. If you want a mixer, an equalizer, and a balancer along with the amplifier, you can choose a channel strip rather than buying all these elements individually.
Q. To which devices can I connect the preamp?
A. A microphone preamplifier can be connected to a mixer, a speaker, your laptop, or any other peripheral device as per the output ports present in the amplifier.