John East Marcus Retro 1-Switch (Without Scratch Plate)



The Marcus Retro 01 was brought about due to requests from players owning the Marcus Miller basses.


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Control Configuration

  1. Volume/Blend Stack
  2. Treble/Bass Stack
  3. Mid/Mid Stack
  4. Passive Tone Push/Pull Active/Passive
  5. Pickup Blend Switch


New For 2013! All New Marcus Retro's control configuration has changed slightly. The Active/Passive switch has been moved to the Passive Tone Control as a Push-Pull. All models have a single toggle switch as opposed to the older dual design. Dual Switch Models available on request

The Marcus Retro 01 was brought about due to requests from players owning the Marcus Miller basses. Most of the circuit is the same as the Retro except that the bass and treble turnover frequencies, or corner frequencies, that are designed to match that of the Marcus Miller pre.

It's high quality circuit uses three stacked knobs plus a single knob. It includes an active blend circuit plus 3 band equalizer with bass, variable frequency mid, treble and bright function. A passive tone circuit is also included which operates in both active and passive modes. A very gentle built in contour gives immediate colour without detracting from the basic sound of any bass. The active blend circuit prevents the loss associated with many passive basses where, when both pickups are up full, the signal from one pickup feeds into the other and vice versa. However, a switch is included to allow a passive equal mix of both pickups.

EASY TO FIT, NO ROUTING OR MODS TO MOST Marcus Miller J DELUXE STYLE BASSES. No Scratch Plate. with Chrome Knobs and Single Toggle Switch.

Technical Specifications

    Volume/Blend Stack

  • Volume

  • The upper knob is the Volume which has two sections under the same knob. A high impedance section is used for the passive path and low impedance for the active circuitry. When used active, this knob has active circuitry after it so that the feed to your amplifier is a low impedance drive.

  • Blend & Pickups Switch

  • The lower outer knob is the Blend balance for the pickups. Turn it fully clockwise for the neck pickup alone and fully anti-clockwise for the bridge pickup. The midway position, which has an indent, gives an equal mix of both pickups. The balance between the pickups is continuously variable with progressive level compensation towards the single pickup settings.

    Please Note Important:- The Pickups switch (by the blend) must be set pointing towards the jack for the Blend to function. In passive mode, the bridge pickup or both pickups can be used.

    Treble/Bass Stack

  • Treble: (+12dB @ 1k5Hz, -12dB @ 1kHz)

  • The upper knob is the Treble control with boost and cut. The central 'flat' position is indented. The cut settings work on lower frequencies compared to boost to give a deeper sound when the top is rolled off.

  • Bright:(+8dB @ 7kHz)

  • Pull the Treble knob for the Bright setting.

  • Bass:(+15dB @ 40Hz)

  • The lower outer knob is the boost only Bass control. The frequency band of boost gets progressively lower as the boost is increased. An indent midway is included to aid the setting of this control.

    Mid/Mid Stack

  • Mid:Boost/Cut (+/- 12dB)

  • The upper knob controls the amount of Mid boost or cut at frequencies according to the setting of the Frequency knob. The midway indent is the 'flat' position.

  • Mid Freq: (150Hz - 3kHz)

  • The lower outer knob is continuously variable and sets the Mid frequencies for boost or cut.

    Passive Tone Push/Pull Active/Passive - Pull up for Passive, Push in for Active

  • Passive Tone:

  • The passive tone pot consists of two sections, one for each pickup. Two sections are necessary since the pickup signals are kept separate and fed to their own individual input amplifiers prior to the electronic blend circuitry.

    To retain the characteristics of a true passive tone, its circuitry is connected directly to the pickups at all times, and therefore it functions in both active and passive modes. The roll-off frequency is set to give a deep mellow sound.

Question: Where Can I Buy a John East Marcus Retro 1-Switch (Without Scratch Plate)?

Answer: You can buy this from Best Bass Gear by Calling 877-839-3531 or Emailing us at or chatting with our Bass Techs


Rate and Review this item
Verified Buyer
By Antonio Solorio Gonzalez
I am absolutely pleased with this preamp; it really opens up your bass tone to a new level. Just the stacked mid control worth the investment, this is something the Fender Marcus Miller bass lacks and John East solve it wonderfully. Add to this an extra switch to control your pickups on passive and active mode and you have all the tones you need for slap, pick or finger style. Installation cannot be easier, just screw your pickup cables, solder the ground cable and you are done. Thanks BBG!
Verified Buyer
Great preamp
By Daniel Stoll
I put this preamp in my MM jazz bass and I was just blown away by the sound of my bass. I kept the original pickups but even with those it sounds killer. Great device and easy to install!