HOW TO ADJUST THE TONE AND GAIN OF AN AMPLIFIER
To get that sound that we have in our heads, we must first
know some essential elements of our AMPLIFIER.
Beyond the differences between the different teams, (especially
with regard to channels and some specific functions), the
vast majority of teams are provided, at least with:
a) An equalizer
b) A gain control.
c) A reverb unit
To get closer to our dream tone, we must know how
each of these devices works.
An amplifier is fundamentally divided into three parts; The
Preamplifier (the “preamp”), the Power Stage and the
Baffle / Speaker.
The preamp levels out the electrical voltage coming from the guitar. At
this point is where the equalizers, channels,
distortions operate . It is in short, where the “tone” of our amp is born.
The Stage increases the signal strength, so that
the speaker membrane finally moves.
A small “combo” contains these three unified elements and a head, preamp and stage.
Except for the Presence and Resonance controls, which operate on
the power stage, the rest of the controls operate on the “Preliminary”.
The equalizer processes the audio signal and modifies the
frequency content of the signal it processes.
We use it to reinforce or attenuate certain frequency bands, in
order to compensate the response of the equipment or to adjust them to our
In guitar amps, these frequencies are divided into three bands:
1- Bass (BASS / LOW)
They embody the sound.
The frequency of the bass is the place on the spectrum where
bassists and drums ” mainly ” live ( mainly bass drum
So, in principle, it is not too relevant for guitarists.
If there is a bass player doing his job well, we don’t need to
fill in the bass ourselves.
In fact, depending on styles and situations, we can come into
conflict with the bass and hinder, forming a tangle of bass (the
dreaded ball effect, ball …)
Unless we play alone, without a band or accompaniment, it is not necessary to reinforce much
the bass; a medium level is suitable for most
2- Media (MID / MIDDLE)
The frequency of means, on the other hand, “yes” is our place on the sound map.
The guitar operates, essentially on the frequency of the media, in this
way, if we eliminate the media, it is more difficult for us to hear ourselves
The more we cut the media, the more “sound pressure” we need to
hear ourselves well.
Apparently when we equalize the guitar alone, without the rest of
the band playing, the media appears annoying and loud.
For this reason, our initial tendency is always to cut them.
That way, the guitar sounds smoother, less raucous, with a
sound similar to a HI-FI team.
The problem comes when the band starts playing. (When the war starts!)
When the whole group is playing at full speed, (the drummer
“stuck” hitting sticks, the bassist giving it his all, the other guitar
trying his new amp, the mass roaring …), then, at that moment, the means are
If our media level is below 25 \%, we are
before a problem; We did not hear each other and although we went up and up the volume,
we never ended up having that “edge” and that “punch” that we need. In the end,
along with the volume, the confusion increases.
The solution in these cases is, first of all, to reinforce the frequency
of the media.
When uploading the media, what we found strident in the solitude
in the rehearsal room, becomes definition, clarity and presence, and
all without increasing the volume too much.
So, very careful with removing the media, it is like erasing us from the sound map.
3- Treble (TREBBLE / HIGH)
With the treble we control the brightness, the “Hiss” and the harmonics of the high frequencies.
It is also not our “place” on the spectrum.
As a general rule, when our sound is clean, it is appreciated to have a
lot of treble. Crystal clear, flared sound, “twang” …
As we play with more distortion, the treble begins to bother.
Even with a high quality amp, with a lot of distortion, the treble
can make you sound “buzzard”, “seedy”, “raucous” …
My tip of the week is; The more distortion, the less treble.
B) GAIN CONTROL, VOLUME CONTROL
At this point there are two key ideas;
1- Input volume.
2- Output volume.
It is important to understand these two concepts well.
This is one of the usual “workhorses” that they are starting from.
Until we understand it, we are not able to master the
distortion and the amp seems to behave like an “entity” with a life of
its own, which gives a different sound every time we plug it in, and tends
to do a little what it does wins it.
The input volume can be found named as:
Gain, Drive, Distortion, Volume, Pre, Boost, Lead …
It refers to the amount of signal that “enters” the amplifier.
If the input volume is high enough, the amp becomes
saturated and distortion occurs. It is similar to what happens when
we scream loudly through a microphone. If the speakers are very
small, the sound becomes dirty, saturated. (The difference is that if we saturate a microphone, a speaker, a mixer, a digital device, or a transistor device, nothing is cool. On the other hand, if we saturate an amplifier de Válulas the thing changes, because it’s cool! )
The guitar volume knob AFFECTS THE
INPUT VOLUME . If on the guitar the volume is 1, we will never get
a forceful distortion. If we want “reed” the guitar must be
at 10 (or at 11 !!).
In contrast, if we want a clean sound, the input volume of the
amp should be at a minimum, or we will lower the volume of the guitar.
A common mistake is to think that the guitar
volume is an output volume. The guitar’s volume is passive, it cuts the
signal, it doesn’t amplify it.
For this reason, many beginners look at me with horror when
I ask them to turn up the volume on the guitar.
They imagine that everything will explode !!!
This whole thing is like when we connect an MP3 player to an
audio system. The player has a volume and the equipment also. If I turn up the
MP3 volume (Input Volume), I won’t thunder unless the player’s
volume is high (Output Volume). (In this specific case, nothing happens if the Mp3 is full, because by nature, it will not saturate the equipment. What’s more, if it is not full, when the equipment is up, the noise will also increase. With the guitar we can play a lot more with the input Volume, to get different effects)
Therefore, the control that makes everything jump through the air is the OUTPUT VOLUME. And it’s not on the guitar, it’s on the amp.
The latter is usually called Master, Post, Main Volume …
This one does control the actual decibels,
INDEPENDENT to the input volume.
It does not matter if the input volume is at minimum (clean sound) or
full. The master raises the volume, as does the volume control on
a stereo, or that of a television.
There is another essential idea that we must take into account to understand how
an amp works.
If the input volume is too high, if we already have a
distortion level (if we are in the “Distor” channel) the amp works as a
If we already have distortion, it doesn’t matter how many more pedals we put between
the guitar and the amp … The sound will become more and more saturated, but the
OUTPUT VOLUME will not be affected.
We can verify it by playing with distortion; It doesn’t matter if we play loose or strong; There are no drastic changes in the output volume, if I
hit the strings hard it almost sounds the same as stroking them. This occurs because distortion COMPRESSES the sound. The
distortion makes FUNNEL.
On the other hand, if we are in a clean channel (with
low input volume ), compression does not occur and it does affect the fact that
we use pedals or that our execution is intense. There will be a big
difference between stroking strings or “clubbing” them.
Remember: distortion compresses the sound.
For a guitar to sound “pro”, it must be compressed.
USUAL CONFIGURATIONS (PRESETS)
We are going to see some of the most common sound “presets”.
1-) CLEAN SOUND
For a clean standard sound, we can set bass to 50 \%, mid to
50 \%, and treble to around 75 \%. The trebles in the clean sound do not
bother and give us a “crystal” feeling.
The input volume, the distortion, should be kept to a minimum.
As in clean sound we don’t have the compression that distortion gives us, I
always recommend to everyone to use a compression pedal for
clean sound and to avoid volume “spikes”.
This is the name given to the sound with a medium distortion level typical of
BLUES, R&R and ROCK in general.
Serious at 50 \%, medium at 50-75 \% and acute at 50 \%.
Profit in half.
As the distortion level increases, the treble should be trimmed to avoid “shrillness”.
3-) DISTORTION (Classic Rock)
For a powerful, thick, and effective sound; set all EQ to 100 \%. (If disturbing, treble may be cut a little). Common for Marshall users. Absolute power.
Input volume Gain, Drive, etc. … full. Easy to Remember.
This preset works great with practice amps. It gives us a
good answer and it sounds thick.
The Jazz Standard is essentially a clean sound (see
clean sound ), but with very little treble.
We can cut the treble with the guitar’s tone control (
we put it below 5) or cut treble on the amp, below
Since the 90s, distortion sound has adopted the
Standard proposed by the “trash” groups in the late 80s.
BASS: 100 \%
MIDDLE: 0 \%
TREBLE: 100 \%
GAIN at maximum
Being a sound with no media, the sound pressure level
required to stand out is much higher than that of a
conventional distortion (see “distortion”). In other words; It takes
many watts for it to be effective.
(You can find a good number of presets of your
favorite guitarists through the network).
C) THE REVERB
Most amps include a Reverb control.
Reverb allows us to simulate a three-dimensional space.
With a lot of Reverb, the guitar moves away and gives the feeling of being in
a large room. With little Reverb, the guitar “approaches” us.
Its implementation in the different sounds is simple:
MORE DISTORTION, LESS REVERB.
If we go from Reverb with the distortion, the sound gets “enguarrar” and
it becomes confused.
In styles like COUNTRY, especially in SURF-ROCK, whose
usual preset is clean sound, Reverb can be set to maximum.
In styles like NU-METAL, Reverb is practically eliminated.
Many amps carry a control called PRESENCE.
The presence affects the treble of the power amp.
So, it comes to work in much the same way as
normal highs , albeit a little more “medium”.
It is called presence because it operates on a
characteristic frequency of the guitar. Through this control we increase
our relevance in the mix, we are perceived better.
In Vox amplifiers, the presence is named “Cut” and
operates in reverse. More Cut, less presence.
The resonance is the bass of the power amp.
Contour makes it easy for us to equalize because it works on all three
bands, bass, mid and treble at the same time.
With contour to a minimum, the equalization curve is shaped like a
“smile”, a “V”; Many bass, few mids, many trebles.
In the middle, the equalization curve is a horizontal line; bass,
mids and trebles at 50 \%.
With Contour on full blast, the EQ curve simulates a
sad mouth ; few bass, many mids and few trebles.
D) SOME USEFUL TIPS
– “Our ear does not perceive the frequencies in the same way when the
This means that getting good sound at home does not necessarily mean that the
sound will work well in the rehearsal room and vice versa.
Personally, I use different presets for home than for live.
Keep this in mind. For each volume, the amp setting varies.
With the volume low we can raise the treble a lot and these are not
annoying, they even make everything sound clearer.
As the volume rises, the treble revives in the form of an
ear “beast” , and the bass becomes a true monster from the depths of hell …
On the other hand, our ear gets tired, don’t forget this if you don’t want to go crazy:
What we perceive after hours of practice has nothing to do
with what we perceive with the “fresh” ear.
So, what sounded great last night, today in the morning I don’t have to
like it and on the contrary.
This means that the equalization changes should be done
slowly, without going crazy to “button”. You have to be
patient and wait several trials to find the best fit.
-The acoustic conditions of the room influence.
Our Amp does not sound the same in the rehearsal room as in the live one. Everything influences. Size of the premises, type of wall covering, whether it is outdoors or not, IF THERE IS A PUBLIC OR NOT, height of the ceilings …
Therefore, there is no definitive adjustment that is valid “forever”. You have to open your ear well to adapt to each situation.
-Sometimes, the problem lies in what is “left over” and not in what is “missing”.
Sometimes, when we do not find the sound, we dedicate ourselves to increasing and increasing frequencies; more bass, more treble, when the problem may be that we are going from bass to treble … (what we perceive as a lack of Bass, may be an excess of treble and vice versa)
– Valve amps sound different when heated.
I calculate that towards the hour or two they give their true tone and level of distortion.
When they are cold, sometimes they are not even saturated.
It is best to leave them on as long as possible before
working with them.
-Use the effects loop (“Send and Return”)
We have mentioned above that a distorted amp works like
a funnel, so if we increase the volume by means of a
pedal before attacking the amp, the volume does not vary; the amp becomes
more saturated, but the volume remains the same.
Well, all the pedals placed through the EFFECT LOOP,
work AFTER the funnel (After the Preliminary) and therefore are
not affected by distortion or compression.
In this way, a volume pedal placed at that point really does
increase the volume.
The effects loop is located between the Preamp and the Power Stage.
By the effects loop, all the effects that have
some parameter “time” are usually placed : DELAY, CHORUS, REVERB, LOOP, PHASER, FLANGER,
– Use good cables.
A bad cable eats the tone and makes noise. Very important the
“hoses” of the pedals, must be of good quality. (Especially if they are long, if not, they also eat the tone)
A faulty electrical installation also influences tone and noise. (Pay attention to the grounding; if it is missing or not properly installed, we will have a real chainsaw inside the amplifier!)
Network cables must be separated from audio cables, to avoid interference and noise.
– The digital pedalboards, better for the “Input”
Most pedalboards are designed to be placed between the
guitar and the amp. They work worse through the effects loop.
It is recommended to connect them to the clean channel, and, place the
channel controls in the middle, since these pedalboards come equipped with their
– The “Master” Volume, a relatively recent invention.
Older or “retro” amps do not have a Master Volume.
In that way, the output volume is controlled by the
input volume and so the distortion level and the output level are
Until the amps had a Master volume, it was not possible to
play with much distortion at a low volume.
-Use the “Stand By” to improve the performance and duration of
Tube amps have two power buttons:
POWER and STAND BY.
The Power powers the amplifier.
The Stand By allows the amplifier to be switched on, with the valves
hot, but in a “saving” mode.
Until we activate Stand By, the amp does not sound, but in the
meantime, the valves are hot without giving full performance.
To make the valves suffer as little as possible, it is recommended to
turn on the Power and wait several minutes before activating Stand
To turn off the amp, just the opposite; first we disconnect the
Stand By, we wait and finally we turn off the Power.
This ritual lengthens the life of the valves.
For concerts, it is best to activate the Power 1 or 2 hours before
playing and, the Stand By, about 20 minutes before the “Show”.
Finally remember that each amp is a world and each guitar is
also. Take it easy and let your ear get used to
the changes. One of the usual mistakes is to start playing buttons
almost without having heard anything and without even checking how the
Do not forget that, in reality, there is nothing “set in stone” and that therefore your intuition and your ear must rule when making decisions.
Our perception of sound varies with the years, with tiredness, with volume, with the guitar, with the pedals, with the room … so the adjustment of the amp is something permanent, recurring, continuous. We have to take it as something that begins and it never ends (Except for those who use the same equipment year after year!).
Remember that the higher the technical or performance level of a band, the lower the volume it needs for everything to sound good.
Whatever happens, if we are “out of plane” (well above or well below the optimum level), it does not matter how we have equalized the amp. Knowing what is the right level for each moment is a sign of seniority and knowing how to be.
Enjoy the fit! See you!!