Geezer Butler Amplifier Rig – “Know Your Bass Player” (2/3)

Geezer Butler Amplifier Rig Rundown

This is part 2 of the Geezer Butler Amplifier Rig. In this episode we explore his amplifiers from the early years to “The End”. Look at his effects and analyse his strings and pickups. Geezer, along side Tony Iommi have been big users of Laney equipment before moving onto Ampeg and then Hartke. Throughout his career, his amplifiers just get bigger and bigger.


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Amplifiers on Black Sabbath

Geezer used equipment that was readily available at the time, recording the album “Black Sabbath” with

This cabinet only have three working speakers which Geezer couldn’t afford to repair.

Laney 70W amplifiers were later re-rated at 60 Watts as they were found to be “too loud”

Geezer recording bass on Paranoid

After the success of Black Sabbath, Geezer upgraded his equipment;

Geezers amplifiers and the era of excess

The brand new Geezer Butler Amplifier Rig debuted around around 1974. At this time he added an Alembic rackmounted preamp for more gain.

  • Alembic FX-1 preamp

Also seen at this time

  • Laney 100 Watt head (x3)*
  • JBL custom cabinets using JBL speakers  (x6 with additional 1 was for back up, 7 in total)
  • Crown power amps (x2) powering 2 bass bins

Geezer Butler and Ampeg Amplifiers

The Sabbath reunion tours in the mid 90’s had Geezer endorsed by Ampeg amplifiers. His typical setup was rackmounted SVT-2 heads.

All 8 cabinets were fitted with Electrovoice speakers. These were custom crafted Ampeg cabinets as at the time 2×15 inches weren’t readily available.

Geezer Bass Amplifier Rig on Heaven and Hell around 2006-10

Geezer dropped the 8×10’s in favour of a uniform rig

  • 4×12″ Custom Ampeg cabinet (x4)
  • 2×15″ Custom Ampeg cabinet (x4)

All were customised with Electro Voice speakers and either a Henry mascot or a Cross grill cloth.

Recording with Ampeg

As an endorsee of Ampeg, Geezer used their equipment on his solo album Ohmwork for GZR and again when recording Black Sabbaths 13

And In addition to Ampeg he also used a Laney 100 watt tube amp.

Geezer meets Hartke Amplifiers

Geezer was invited to play the yearly Dimebash in 2011. Hartke amplifiers provided the backline for this event and it is here Geezer first played Hartke.

He has stated in interviews that Hartke (Kilo) was easy to use and sounded very close to early Sabbath.

An endorsement was agreed where he used the following on tour

  • Hartke Kilo (x4)
  • 4×12″ Custom Hartke cabinet (x4)
  • 2×15″ Custom Hartke cabinet (x2)

The 15 inch cabinets were custom as consumer 2×15″ were not available.

Ashdown Amplifiers and The End tour

During The End tour, Geezer acquired a new bespoke rack mounted preamp and matching amplifiers made by Ashdown.

This rig was named the Geezer Butler Custom  “Hand of Doom”.

  • ABM-RPM-GZR pre amplifier (x2)
  • Ashdown RPM 1000 Stereo amplifier (x4)

It’s purpose was to be able to separate the high and low signals to run at full range. The preamp was also fitted with an additional tube preamp.

This was a custom product made by Ashdown and not for sale to the public.

Ashdown Hand Of Doom setup

We here at have been in contacted with Ashdown and they’ve been kind enough to explain the details of this rig.

Geezers signature unit (not to be confused with the consumer Head Of Doom, see below). Took an existing John Entwistle custom preamp, which was based on an EVO II.

They then created additional modifications to the existing crossover, giving the unit 4 outputs instead of the usual 2.

These 4 outputs were connected to 2 Stereo Ashdown APM Amplifiers where only his 4×12 cabinets were powered.

This was repeated again and the second set was used to power all four 15 inch cabinets.

All in all he has 2 GZR preamps connected to 4 APM power amplifiers which can power up to 16 cabinets if he desires but we see him on tour with just 8 in all.

The Geezer Butler Head Of Doom

Ashdown released a consumer signature Geezer Butler amplifier head which will consolidate this set up and downsize it dramatically. Housing the pre-amp and amplifier together in one unit.

Rated at 666 Watt RMS, hand built in the UK and designed around Geezers requirements previously mentioned. The Head of Doom is for bass players who seek classic, driven bass tones with phenomenal power.
And With a bunch of additional extras.

Geezer Butlers Effects

Most of Geezers sound if made by the way of an overdriven tube amplifier. He runs his amplifiers extremely hot to the point where you can hear the warm analogue overdrive.

Tube amplifiers, like Laney, Ampeg and Hartke are the classic go to’s for this sound. The Hartke Kilo gave Geezer a sound reminiscent of the old Sabbath days with little EQing and a very warm pleasant sounding overdrive.

Collaboration with Dunlop and Geezer Cry Baby

The only other effect you will hear during Black Sabbath is a Wah typed sound and that’s on NIB.

The original was recorded with a Tony’s Tycobrahe wah pedal. After aquiring his own it has been known to use his own throughout the years in Black Sabbath and Heaven and Hell.

Geezer released his very own Wah effects pedal in collaboration with Dunlop. It’s designed to retain low end frequencies while allowing an aggressive midrange to cut through the mix.

During NIB on“The End of the end” DVD you can see on stage a Dunlop Q Multiwah which the signature was based off.

Geezer Butler and Bass Strings

Geezer has been using heavy gauge hand made K3 DR strings since the early 2000’s. These strings have a usual string gauge of 50-110.

Since Winter 2010, he changed to DR’s Black Beauties. The thickest E string is limited to .110. and t he next size up from would be a .120. Which is the same gauge as a B string on a 5 string bass.

DR are now sending Geezer custom .115’s to to counter this issue. Making it easier to play in C and C# tuning.

Geezer Butler EMG Pickups

Geezer has been using EMG pickups for many years, using their vintage models in his BC riches back in the 80’s and now again today with his signature set in his Laklands.

In 2014 Geezer released his very own signature pickup for Precision and Precision Jazz basses.

Designed in a vintage style but built with a few modern touches. The P set uses Alnico 5 pole pieces with custom wound coils.

The J-style pickup in the PJ set has two wound split-coils that eliminate the noise and hum usually associated with early 70’s bass pickups. Allowing for more power and volume than any other standard single coil J pickup.

Geezer Butler’s Effects Rack – Part 3

In the concluding video of the Geezer Butler Bass Rig, we look at the on stage rack units, microphones and touch on some follow up over the series.

More from Know Your Bass Player

This has been the final artist in our first season but don’t worry. There’s been a few things missed out during this episode that a bonus video will be coming out soon. In addition to this a channel update viddeo will be posted to the to the YouTube channel shortly, where more news will be revealed about season 2.

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Watch more Bass Rigs

Have you seen our previous episode? In the last Know Your Bass Player we took a look at the Geezer Butlers Bass Rig 

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