For years and years there's been all kinds of "Expert Opinions" on the Internet about how Eddie got his tone. First thing we need to address is Eddie's "Famous Marshall 100 watt Super Lead Plexi Amp". For years, It was claimed the Amp was modified by Jose Arredondo. It wasn't modded. Jose simply changed the Valves in it and serviced it for him. The Amp might possibly have been rebiased by Jose.
The reason being I know the Marshall wasn't modified because Mike Soldano did some work on that Marshall sometime in the early 90's after Eddie bought 3 Soldano SLO 100's and 3 4 x 12 cabinets from Mike Soldano.
The Soldano SLO 100's were Eddie Van Halen's and Andy John's choice of Amp when For Unlawful Carnal Knowledge was recorded. Mike stated the Marshall was totally stock. Mike even rebiased one of his Orange Amps and got the exact tone of Eddie's Marshall.
Ok a slight bit of History regarding Eddie's Setup from 1985 onwards. In 1981/1982, Studio guitarist Michael Landau was about to go out on tour with Olivia Newton John.Let's get Physical, Olivia Newton John. Michael Landau needed to be able what he could do in the Studio in a Live Situation so he hired Bob Bradshaw to designed a signal switching solution for his amps, pedals and rack gear(not 100% sure if Landau was using rack gear at that point).
Mike Landau at that time was one of the most well known Studio players in Los Angeles back then along with Lee Ritenour and Steve Lukather. Jay Graydon and Larry Carlton had retired from Studio work by that time. Jay Graydon was producing records by that time and Larry Carlton was busy as a solo artist.
Word travelled quickly about the brilliance and expertise of Bob Bradshaw and soon he was making rigs for Steve Lukather and many of the Studio Players in Los Angeles. It was also in the early 80's that Studios expected Guitarists, Keyboard Players and Drummers to have Studio quality effects when they would turn up for Sessions.
This meant players would have Rack Effects MXR, Ibanez, Roland, Eventide, Lexicon etc. Much of these Studio Rack Effects were becoming affordable for Professional/Players with Record Deals. $1000 to $2000 for a reverb was affordable for the Studio player that was doing 20 to 30 Sessions a week or for a player who was selling millions of albums.
In 1984, Steve Lukather got his first Bradshaw Rack System. You can see it on the Steve Lukather StarLicks Guitar Lesson Video from 1984......it is on Youtube. Many, Many rock players were beginning to use Rack Systems from 1982/1983/1984 onwards.
Eddie Van Halen and Steve Lukather were good friends since the late 70's and when Eddie saw Steve Lukather's Bradshaw rig he went and got one for himself.
Steve Lukather's Rack System was a Stereo Rack System. A left Channel and a Right Channel both with effects on them. Specifically with a Delay set to a certain speed on the Left Channel and a Delay set to a certain speed on the Right Channel. Generally, One would be set for a faster speed and one would be slightly slower. Lukather also used a Dytronics Tri-Stereo Chorus.....which had a Chorus for the Left
Channel, a Chorus for the middle Channel and a Chorus for the Right Channel.
For anyone wondering about the Dytronics Tri-Stereo Chorus. There is a company that has started manufacturing it again recently, it's amazing sounding, but it costs $3000 or $4000!
Eddie he insisted on having a Tri-Stereo Rack System. Unlike other players, Eddie had effects on his Left Side(WET) and his Right Side(WET).......but he had a middle Amp with no effects on it (DRY) with perhaps the exception of a noise gate.....specifically a Rocktron (I know for fact Eddie used a Rocktron with the Peavey 5150's as they create horrible noise when cranked). This is why Eddie's Setup is termed WET/DRY/WET. Dry means straight signal, Wet means effected signal (Reverb, Chorus, Delay etc.).
Why did he do things that way? Simply because all of the rack gear you use is connected together.....if a cable fails or the power goes down in any piece of the rack gear......you loose all sound! If any part of his rack was to fail.....he would still have his main amp until the problem with the rack was fixed.
Having a DRY middle Cabinet/Amp also doubles as a very useful "Monitor Speaker".
The "DRY" Amp would then have a cable coming out of the "LINE OUT" of the Amp and it would go into whatever Rack Unit was first in the signal chain. The Rack Unit would be then connected to 2 Amp Heads.....One Left Side and One Right Side.
Oh......Just in case if you are wondering how many Amps Eddie used Live? He used 3 Amps with 3 4x12 cabinets! As for the effects Eddie used...Eddie used a 2 Roland SDE3000 Delays (Set at Different Speeds to add Ambience), An Eventide Harmonizer(H949 and later a H3000, this was used for micro detuning his guitar), A Lexicon PCM70(For Reverb and Chorus), Furman Power Conditioners would be used in the Rack to get rid of any unwanted electrical signal coming from the power supply at the venues played.
All of the Rack Units were controlled by a switching system designed by Bob Bradshaw which wasn't MIDI.
Eddie also used several stompbox pedals too such as a Flanger and Phaser mostly likely MXR and he also had a BOSS Overdrive which he rarely used.
Throughout the years from 1985 to 2015, Eddie's rig didn't change too much apart from the Amps he used.In the 1980's, he used a variety of Marshall Amps, Then for a short while in the Studio in the early 90's he used Soldano. Then he used the Peavey 5150's until he did the deal with Fender to make the EVH Branded 5150 Amps.
Should be pointed out that Eddie owned a dozens of Amps including Fenders, Riveras, Dumbles etc. It has been said that the Amp Eddie used to record the "Beat It" solo was a Hartley Thompson owned by Allan Holdsworth (I read that somewhere). However, a friend of mine recently bought a Rivera Knucklehead 100 Amp head and my friend spoke with Paul Rivera on the Phone and he told my friend that Eddie used an Amp he Built to record the Beat it Solo.
Denis J. McCarthy, EVHGroup