Gibson GA-4RE Oil Can Delay

This is the first of our “Weird Gear” series where we’ll be writing about some of the more interesting and unusual equipment we employ.

“The GA-4RE records music with an electric pen. The recode is made
on a film of oil which also serves to lubricate the revolving disc
which is the platter for the film. The film is constantly replaced and
can never wear out like magnetic tape. Following the electric pen are
two sensors which reproduce the pattern of electrons for the
amplifier. The effect is a multiple choice of echo and reverberant
sound with a quality never before achieved.”

– Gibson Reverb-Echo GA-4RE Instructions

The GA-4RE is a staple sound of The Mesmers. It’s haunting, warbly
echos have made it’s way into numerous songs including “The Model”,
“Neptune City”, “Race The Days” and most notably “Sandy Strange”. It
was manufactured by Tel-Ray, a California electronics company which
eventually become Morley, as a licensed/re-branded version of it’s
“Adineko Memory System”. It was available during the 60′s as an
alternative to high maintenance tape delays and can be found in many
standalone and integrated effects under the brands Fender, Gibson,
Rickenbaker, Acoustic, Univox, Vox, and Standelle.


The delays from the oil can have reduced high and low frequency
content. There is also an audible chorus effect due to the
non-linearities of the oil passing the rotating platters. These
non-linearities are impossible to capture using convolution based
methods, so you’ll just have to break down and buy one.



  • Input 1 is for electric guitar.
  • Input 2 is for high z inputs like a tape deck or mixer foldback.
  • Loudness: this is an input attenuator for input 2 to accommodate a variety of high level signals.
  • Direct: this is a volume control for the input (non-echo) signal.
  • Reverb: this is a volume control for the echo signal.
  • Mode: this controls the echo rate and feedback via 3 presets.
    1. Position 1: soft delay with quick repeats and short delay time… as close as this thing gets to reverb.
    2. Position 2: delay with long delay time, great for dub.
    3. Position 3: delay with short delay time, this is the rockabilly position.
  • Power: this, um… turns it on/off.

In addition to the inputs and controls listed above, the GA-4RE also
has a fuse, output jack and footswitch which enables/disables the echo
effect. This unit is all tube and has one 12AU7 possibly used as a
phase inverter and 2 6EU7′s for amplification.


6 Responses to “Gibson GA-4RE Oil Can Delay”

  1. devangparekh says:

    Send a resume out to them but i doubt they’ll hire you. Testing new gear is usually reserved for the current employees

  2. MacGyver206 says:

    It shouldn’t be

  3. lux_interior says:

    non-linearities are impossible to capture using convolution based
    methods, so you’ll just have to break down and buy one.”

    You may be right, but that would not mean that it can’t be mathematically reproduced through a computer model. Incredibly more complex procedures in geosciences, genetics, astrophysics etc have been modelled successfully so far.

  4. Daniel says:

    I just bought GA-4RE. The prevesious ownew said it worked until he replaced the oil. Now, it powers up but, nothing. Where do I start. Thanks, Daniel

  5. Jay Ridgeway says:

    @lux_interior. I totally agree w you. I was referring to existing methods for recording impulse responses, not dynamic convolution.

    @Daniel. I would start by replacing the oil with UCON LB-65. You can find out where to buy and how to clean/replace at

  6. Hi, just doing some research for my Gibson Guitars website. Lots of information out there. Looking for something else, but cool site. Take care.

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