All posts by dimirock


Distortion pedals design is based on hard clipping which provides a huge amount of
gain – distortion.  Aiming for a sound produced by high gain amplifiers.

Distortion is one of the most avoided and at the same time desired effect or defect  of audio, used by audio engineers and musicians.
Distortion alternates the shape of the wave form, produced by audio signal, and when it comes from a device which is intended to provide the best clean sounding signal – such as a PA or Studio Monitor, its a disaster to the audio engineers and audiophile music lovers.
Image credit: Wikimedia Commons)

After years of using tube amps, guitar players discovered the musical side of distortion produced by pushing their tube amps at limits, where the pre-amp and power amp tubes /which are designed to amplify the signal/ started to produce distorted signal.
This changed the instrument sound /in this case the guitar sound/ to long sustained – “dirty” – compressed, and at same time distorted tone which became a brake point and opened many new horizons.

During the late 70’s and 80 rock and metal guitarists like
Eddie Van Halen used some tricks to push their amplifiers by lowering the voltage and turning up the volume, using device called
A variable transformer that lower or rise the voltage going to the amplifier.
This experiment /which rumors were telling/  happened by accident, and produced a high gain – insanely distorted sound of his guitar.
This changed the history of the rock and metal guitar completely.
All of this happened on an old Marshall Tube Amplifier.

Distortion pedals started to show up a few years later
after fuzz pedals and overdrives.

Many guitar pedal builders and manufacturers like MXR – Jim Dunlop and Roland have started to build pedals which were intended to give you that high gain distorted guitar tone.

Names such as: Metal Zone, Metal Master, Super Lead, Turbo Distortion, and so on  were showing year after year to feed the hunger of the new age guitar players, who play at home on their practice amplifiers or gigging world-wide.

The Distortion pedals were designed to push guitar amplifiers harder and to produce that huge, crushing high gain – distorted signal.

Distortion+ yellow box. 
One of the most famous distortion pedal (1979).
It is using single op-amp and two germanium diodes.
LM741CN op amp

A combination which produces soft clipped distorted sound.

This pedal can push your amplifier input to that 80’s early hard rock distortion sound.
Randy Rhoads in his work with Ozzy Osbourne made this pedal famous with his recognizable heavy metal guitar tone.

DS-1 – 1978
it was the first distortion pedal made by Roland under the name Boss.
This pedal is really dynamic sounding, although it is a high gain pedal.  The Orange box become one of the classic guitar pedals used in many genres.
Bands and players like Nirvana, Joe Satriani, and Steve Vai have made this distortion a true legend.

Although its a distortion pedal, players like Vai and Satriani, are using it to shape their tone and adding more gain on top of their amplifiers lead channel, producing unique tone for solos.

Try it on clean channel with settings like – Volume 12, Tone 15 and Distortion on max.
This will give you really powerful and heavy sound with clear chord notes separation.
Underestimated by many, it is still one of the best distortion boxes and it’s still in production.

Years later, the distortion pedals became more and more complex in their design.
Now the modern high gain distortion boxes are emulating the tube amps pre-amp section with cascading Mos Fets and JFets transistors, instead of using Op-Amp and diodes to distort the signal.
This claims to give you more tube like saturation when the Fets are properly biased and matched. / Like the tubes /
But that’s another topic. 🙂
If you hungry for knowledge go and check out this article:
They are so called “amp in a box” distortion pedals.

Some famous amp builders have their equivalents of their flagship amplifiers made in a pedal housing, using Fet transistors.
One great example is: Bogner Ecstasy amp and its pedal version Red Pedal.


Now the guitarists world is fulfilled with many distortion pedals claiming to give you the tone you have never heard before, but you will never go wrong with a few selected classic pedals which are the blue print and the source for the new well known old.

Using them with guitars, synths or using them as a secret mix tool to add a saturation to your |cold| mix
Distortion pedals will continue to inspire us.

Over Drive

Overdrive pedal is designed to simulate the creamy sound of an overdriven tube amp or to provide a gain boost of a tube amp.

Overdrive pedals  are classic sounding-tone shaping guitarist’s tools, mostly used to increase the amount of gain (distortion) that you get from your amplifier.

The most copied pedals ever made are TS-808 and TS-9 pedals which first showed  in the mids 70’s. The technology started to grow up and many companies started to produce transistor based amplifiers.
photo credit:

The Tube Screamer pedal was the answer to give your brand new transistor amp – the tubes magic. Giving you that “vintage tube” sound, harmonically rich and crunchy sounding in a small footprint.

Many modern “boutique” pedals are based on the anatomy of TS OverDrive.

One of the significant character of the famous overdrive circuit is:
To preserve the tone – frequency character of the guitar and amplifier and keeping the guitarist dynamic expression.

Basically its a pedal achieving over-driven sound based on op-amp Japanese JRC-4558 chip  and using two silicon diodes to  produce soft, symmetrical distortion stage.

Over the years pedal builders were changing the clipping stage in the overdrives from silicon to led diodes or germanium ones which are giving the feeling of saturation only achieved in the real tube amps.
LED diodes are giving more headroom and less compressed feeling.
Many models are offering different clipping stages to choose from, using switching system between different diodes.

The famous OverDrive was brought to the listeners  and guitarists by  SRV in late 70’s , which later become one of the most iconic guitar sounds ever made.

Later in the years they began to show up in many modern guitarist pedal boards  as rhythm and solo boosters. Helping many shredders and Guitar gods getting their tone to the next level, a huge high gain with endless  sustain.

Today’s Djent 8-9 strings guitarists will be lost if these pedals don’t  exist.
The low end produced by these guitars is always controlled and shaped by TS based overdrive pedal in front of high gain amp to keep the low end tight and well pronounced.

But don’t forget about their original purpose, they are really helpful to shape your bluesy – rock tone.  You must try them in your clean channel and you will get that vintage tube like saturation with a little tweaking of your amp settings and pedal.

Get a Fender, an amp with nice tweed voiced clean channel and put your OverDrive pedal in front and you will get instant SRV tone in seconds!

So, as you can see, its one of the most used tool from 70’s to
present days.
Every guitar player has at least one in his pedal board to give his tone more distinctive voice and unique sound!

Most of the time you will see the OverDrive with settings like: Drive-Gain knob at zero, Tone at middle and Volume knob almost at max  in front of a tube amp, transistor or modern software amp simulator, giving a tight low end or screaming full with harmonics rich lead tone.

When your amp needs a little magic or your solo tone has no sustain, the overdrive pedal is the tool you gonna need!

Used from SRV, Steve Vai to Animal as Leaders, its a legend that will live forever. 🙂