What is a Preamplifier – Why is it Important?

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Written By Tanya

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It works like this: A preamplifier is required for recording with a microphone, without any questions.

You can record with one, and the same chance of getting terrible results. This is why I am so insistent about it. I didn’t know what I was doing when I recorded my 30 first songs without one. I was more interested in recording my art than learning the technical aspects of how it should be done.

Preamps can be found hidden all over the place, which is what makes it so funny. They’re built into mixers. They are built into USB microphones (for all that is good, holy and beautiful, please don’t use them). Even a inexpensive audio interface has them. Some soundcards have them.

They are so invisible that most people don’t even know they exist.

They exist because they are necessary. But the question is: Why? What are they doing? Are they able to do their job well? Can they do their job well? What happens if one is missed? I have the answers and you’ve got all the questions.

Because all microphones have a characteristic that allows them to record a mic-level signal, the preamp is necessary. They record a mic level signal.

Preamp’s Fundamental Purpose

We said that microphones record signals at mic-level. This is when acoustic wave vibrations through the air and jiggles a diaphragm forward and back. This causes a magnet to move in a wire coil, and generates an electric signal.

This signal is weak and so it has its own name mic level. This is also true for signal-level signals.

All of our recording gear, including equalizers, compressors, analog-to digital converters, and the like, expects a line level signal. Line-level signals are at a higher voltage which means they have a louder volume. This is what you hear from keyboards and electric guitars.

The challenge is to elevate a mic-level, instrument-level signal to a line level signal. This is the main purpose of preamplifiers.

This is the main reason preamps are used.

There are two types of preamplifiers

Preamps are designed to increase the volume of mic-level signals and do so cleanly. The goal is to increase the signal without increasing the noise floor or other problems that might be picked up along the route, such as electrical hum.

Pre’s that increase your signal to reproduce the exact sound recorded by the microphone are known as Transparent.

This is the problem with not using preamps. The signal can be run into an instrument input, or into a soundcard. You can crank up the input gain to get a usable signal that you can record into your digital music workstation.

You’re also cranking up the volume. You can turn up the noise floor to get the desired signal. This results in a high signal-to noise ratio.

You can start with your Acoustic Treatment, then your microphone and finally your preamp. This allows you to control the signal and keep it clean through Gain Staging. This is part of being a recording engineer.

It’s back to the basics. Solid state electronics create transparency, but preamplifiers of old used tube technology (just as cathode-ray tube televisions). Modern solid state pre-amplifiers use transformers.

Pre’s that utilize transformers and vacuum tubes can increase your signals volume while giving you a specific color.

The term coloration, color, flavor… all refer to the warmth that your signal receives as it passes through the transformers or tubes. The signal is subject to a pleasant distortion.

This harmonic distortion is created by the signal at very low volumes and lower frequency. It gives the signal a feeling of warmth.

The art of making transparent preamps has been mastered by manufacturers (although not all are willing and able to spend the necessary electronic parts). Many of the big boys who already have transparent models offer colorful versions.

This is a subtle feature that 99 percent of listeners will not notice. Don’t worry if you’re looking for , buy the best microphone preamp, and have a conversation about coloration.

First, think about the base quality. The top level flavors are very similar, and people can argue about them. (Studio engineers have learned how to hear every uniqueity!) ).

What do all the knobs and inputs do?

Preamplifiers are well-known, but how can we get them to do their job?

Two types of inputs are common in preamps. One is the XLR input, which accepts your microphone cable, and the other is the TRS input, which accepts your electric instrument cable (keyboard, guitar or bass). ).

The second type will be labeled “Instrument” and “Hi-Z”, the abbreviation of “high impedance”. We’ll soon be discussing impedance.

It’s not enough to just plug in your instrument or mic and be at the right volume. You must perform gain stage.

Every piece of studio equipment needs to be able to receive a signal at a specific level. This includes compressors, preamps and EQ’s and, most importantly, your analog-to digital converters. This is the purpose of the Gain knob.

Gain refers to the ratio between your input and output. The gain knob controls how loud your volume is. This tells the preamp how much signal boost is needed.

Some pre’s come with lights to show you the level at which you are operating. If you don’t have a DAW, you will need to monitor it. There will also be Trim knobs, which are basically the same as Gain.

You’ll also see a few buttons, switches, and knobs. An impedance knob is often found on solid state preamps that have transformers or vacuum tube preamps.

This alters the amount of harmonic distortion that your signal will receive. This is what gives you the pleasant color saturation that we discussed above. This option is not available to all. It doesn’t matter which way you go.

You’ll also see buttons for Invert which simply flips the phase. This can be useful when recording stereo signals like an acoustic guitar with a double microphone and having phase issues.

Inverting either the left or right channel will usually solve it. You will also be able to deliver 48V of Phantom power. This is a requirement for many mics, and the preamp can deliver it.

You might need to turn off the phantom power if your microphone has an external or built-in power source.

Form Factors: 500 Series/Desktop / Racked

You’ll be astonished at the variety of preamplifiers available for different types of outboard gear.

There are some that are oddly shaped and can be placed on your desktop. Others are longer and more horizontal, which can be mounted onto a rack with other equipment. You can also get the lunchbox that will accept 500 Series-shaped equipment. It can be racked, or it can sit on your desk. Desktop Style

Below is a single channel desktop amp. Many musicians, like singers and rappers, only require one channel to record their vocals. They don’t need much other equipment than a preamp or a microphone, so it is easy to keep it right at their desk. Rackmount Style

Rackmount is a good option for anyone who has a lot of different types of studio gear. The chassis’ width and holes are standard for 19-inch rack rails. I use this because I also have EQ’s and interfaces. 500 Series Lunchbox Style

The 500 Series units are also available. The units are placed vertically in a “lunchbox”, which often has a handle, as shown on the left. There are three types of lunchboxes: four, six, and eight. Rack ears can be attached to the largest lunchboxes and converted into a rackmount style.

The 500 Series models are more affordable than other options, but only after you have bought a lunchbox. They are more affordable because they only have one channel and a faceplate, rather than a huge chassis.

This is a great option for people who like to have a variety of options. If you’re interested in creating your own channel strip, add gear from all kinds to your lunchbox.

There are many channels

Preamplifiers come in three types:

  • One Channel
  • Dual Channel
  • Many Channels

The single channel formats are shown in both the desktop and 500 styles. Dual channels are preferred to record stereo signals with the same electronics. You have not seen the models that can feature four channels, eight, or sixteen!

This is the most cost-effective way to get enough channels to record a whole band live or at a concert. These are not the best options because you will most likely get mediocre preamps. Focusrite’s Octopre 8 Channels

The really great ones can run up to $1,000 per channel. Multiply that number by 8, or 16. You can still buy preamps and converters for $300. You should get my point.

They aren’t necessarily of poor quality but they won’t wow anyone. If you are looking for a low-cost way to start drumming, this could be a good option.

Channel Strips Preamps

channel strips are the last thing we should mention. These rackmounts include a preamplifier that leads to a compressor, which then leads to an equalizer. It contains all the major components of a recording system. This configuration can be used to create amazing preamps, such as the Avalon VT737sp. Avalon, VT-737sp Strip

One of these was my loan for six months. It blew me away. This is what inspired me to add a little compression to my mixes instead of drying them completely. It also helped me avoid distortion and unexpected peaks. These are available, and they can be very useful and great additions in a studio.

What’s a Preamplifier, you ask?

Now you know all there is to know about preamplifiers, as well as how to make them. You can also check our review which lists the top preamps for each price range. You now have a detailed answer to anyone asking you “What’s a preamplifier?”

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