The amplification for electric guitar
When you think about a guitar player, he is always thinking of a human who picks up his guitar. But what would be the electric guitar without his amplifier? Without its sound reproduction system?
With the birth of the electric guitar, the amplifier has always had a complementary role.
Togheter with the electric guitar, the amplifier is the sound machine of every great guitarist.
Let’s go throughout the amplifier and see how it’s done.
The amp is made by these 3 elements:
•the power amplifier
•the speaker cabinet
How does it work? The preamplifier increases the input signal of the guitar pickup; after being increased, the signal passes in the power amplifier that swell it in order to let the speaker cabinet move. Now the amplifier generates a sound that comes to our ears by moving air.
There are various construction and assembling systems of these 3 elements. Now we will examine their differences and strengths and weaknesses.
“The Combo System”
In this system the 3 amplification elements are togheter in a single cabinet.
Light to carry
The Combo has the advantage of being light to carry, if there are some models fairly heavy, four wheels are mounted under the cabinet to make transport easy. This feature is often underestimated, but I can assure you that if you play often and make many kilometers, carrying around some heavy vabinet is a real curse for your back, especially after playing a couple of hours with maybe a 5kg guitar on your back.
The “brand” sound
By purchasing this kind of product, you have the advantage of having the three elements designed and assembled to work synergistically to produce a tone that has already tested as choice by the producers.
With the combo play it safe, you turn it on, you try it, you buy it if you like, go home or on stage and sound the same. Simple and direct.
The combo cover the entire market segment, even with a hundred Euros you can have one, then of course it always depends on how much quality you need. They come in any price.
Being perfectly constructed to let work the elements in synergy, it will be more difficult to make sound experiments testing different products and making them work together in order to obtain a sound more detail.
Sound control limited
Except in very expensive special cases and in any case with a more modern philosophy of building, usually combo have little chance sound management.
For example, not always channels Clean and Crunch have some separate equalization commands (Bass, middle, treble, presence), almost never have a master additional volume for solos, you can find the send / return in series or in parallel (see later, in the specific articles, the difference). Many times there is the chance to connect an additional cabinet to use more speakers. A combo with a single 12-inch speaker have a limited amount of volume.
In my opinion, the Combo is, finally, the best starting choice for a guitarist and it’s still a great solution for many professional musicians too. It gives a lot of satisfaction, especially if you already know what you want from an amplifier and if you decide to show your own style with the classic tones which are now a standard in the music business, such as Fender, Vox or Marshall but also Mesa Boogie , Engl and other more modern brands.
“Head and Cabinet” system
The head and cabinet system consists to join the preamp and power amplifier in the same furniture (head) and the speakers to another one (cabinet).
Great tone, big volume
The head, usually 100 watts, has a really big sound, also created by the amount of these valves and the high wattage. If we add the fact that the sound goes through a cabinet with 4 speakers instead of one, this solution can be called a real “tsunami sound”.
Many guitarists onstage, prefer to miking the cabinet to get the guitar sound into the monitor in front of them, to feel themselves. Many others like to hear the sound comes out the cabinet of the amplifier, as they have always heard. The sound, once released from the speaker of the cabinet, is captured by a magnet (the microphones) and repeated in another amplification system (the P.A., the one of the club, for example) and the result is not always optimal.
Finding yourselves on a big stage 3 or 4 meters away from the amplifier, directing a cabinet with 4 speakers to your position, you’ll be fine to feel … With a combo it will be very difficult …
Greater sound management
Usually you have 2 channels with their equalization controls and, in addition to the gain, volume for each channel that converges in the master final volume, in the modern heads you can have up to 4 different channels with their equalization.
Usually you can also find a reverb regolation, then you also have an effect to take into consideration.
The chance to connect multiple speakers (You really need other? Some people think so).
The modern heads also have MIDI inputs and outputs that allows you to manage external devices that we will see later, like pedals, processors and effects.
Heavy as hell!
The head is fairly heavy. Always try to get help in loading and unloading, do it for your back.
If you are looking for a classic tone, even with the head and cabinet, like with the combo, you are in the right direction. But, if you are part of that kind of guitar players seeking maximum versatility and sound exploration, using head and cabinet combined with thousand other rack units may not be the ultimate solution, the limitations over sound control still exist.
When the preamp, power amplifier and cabinet are manufactured in three different containers, the amplification system is called Rack.
It always depends on how big it is, but usually, if we speak only with the first three elements that make up the amp, the Rack is lighter.
The 3 elements, when they are separated, are very manageable in transport, however usually the preamp and power amplifier are mounted in a furnitures called Flight case for easy transportation.
With the rack system you can keep up the work to try different combinations such as a Marshall amplifier with a Mesa Boogie power amplifier and a Fender chest, Vox or any other brand.
The combinations are endless, find out your sound!
MIDI management system
There are many preamps on the market with MIDI system. This system replaces the channels (clean, crunch, lead) with presets, ie the ability to store many versions of the same channel. Usually midi presets available ready to save are 128 and can be accessed with a pedal that changes in real time all the settings. You don’t have anymore act on the analog knobs and turn them with a picture of how they were before that you changed them.
You can use stereophony
Electric guitar is an instrument that emits a mono signal and therefore also its amplifier works in the same direction.
Keep in mind that if you used a rack system, you may take advantage of a stereo power amplifier that is connected to two different speakers (left and right) and it can distribute your sounds and effects in stereo
This approach is usually used by guitarists who work a lot on sounds effects such as The Edge of U2
Great knowledge of sound management
This system has a lot of different variables, not to mention that the sound is often not only generated by analog machines but also to digital modules, and then the sound in addition to the valves is also good in proportion to the quality of its analog / digital converters.
The various rack units are very difficult to manage and involve a great mastery and knowledge of the amplifier and all the machines that match eachother.
Cables, cables, cables everywhere!
You will need many more cables to wire all the rack units, each module has its own power cable, your pedals in front too; in short, you begin to see your position as an island of material with you in the middle.
Get organized with a flight case and power strips to make the assembly and disassembly as simple and clean as possible.
In the next articles we will go throughout each of the three elements to understand better, what it looks like, how to use it and how to create great sounds and guitar tones.
[L’Amplificatore per Chitarra Elettrica – Articolo di Marco Mariani]