Michell Engineering Iso Base

The Iso Base isolation platform is a refined technical solution for mechanically decoupling turntables from unwanted vibrations. Designed by Michell Engineering, a renowned British manufacturer with over five decades of expertise in high-fidelity turntable design, this accessory reflects a rigorous approach to optimizing analog playback.

Transparent polymethyl methacrylate construction: a considered technical choice

The Iso Base is built on a monolithic slab of polymethyl methacrylate (PMMA), commercially known as Plexiglas or Perspex. This transparent thermoplastic polymer offers characteristics particularly well suited to vibration isolation in audio equipment.

PMMA provides a singular combination of mechanical and acoustic properties. Its amorphous molecular structure gives it high rigidity—comparable to aluminum—while maintaining internal damping properties superior to metals. This duality enables the material to avoid direct transmission of vibrations while effectively dissipating residual vibrational energy.

With a density of 1.2 kg/dm³, polymethyl methacrylate remains relatively light while retaining remarkable dimensional stability. Its optical transparency exceeds 90%, surpassing even mineral glass. This aesthetic characteristic allows the Iso Base to blend visually without obscuring the components it supports, creating a particularly elegant visual suspension effect.

The material also offers excellent long-term stability. Unlike certain polymers that degrade or yellow over time, PMMA maintains its mechanical and optical properties over several decades. This durability ensures consistent isolation platform performance over time.

Four-point architecture and Tenderfeet: the synergy of isolation

The Iso Base employs a four-point support configuration, integrating Michell Engineering’s Tenderfeet. These anodized aluminum isolation feet serve as sophisticated mechanical interfaces between the platform and the installation surface.

The Tenderfeet feature a conical geometry terminating in a point. This design drastically limits the contact area, thereby reducing mechanical coupling with the support. The underlying physical principle relies on concentrating the load at a minimal point, creating a mechanical impedance discontinuity that attenuates the propagation of structural vibrations.

The anodized aluminum used for the Tenderfeet contributes to isolation in its own right. The anodizing treatment creates a surface layer of aluminum oxide, altering the material’s vibrational transmission properties. This layer acts as an additional barrier to micro-vibrations, particularly in the mid and high frequencies of the audible spectrum.

The four-point layout, rather than three, offers increased stability while allowing precise leveling. This geometric configuration distributes the load uniformly, avoiding localized stresses that could generate unwanted resonances in the structure.

Compatibility and versatile use

Initially developed for Michell Engineering’s Gyro SE and Orbe SE turntables, the Iso Base demonstrates broad compatibility with a wide range of audio equipment. This versatility stems from its neutral design, free from dimension-specific constraints tied exclusively to Michell turntables.

The absence of proprietary cutouts or fittings allows installation of various turntables, CD players, preamplifiers, or other components sensitive to vibrations. The maximum supported load, while not specified in the technical documentation consulted, is suitable for common home equipment, from lightweight turntables to more substantial models.

The platform performs effectively on different types of surfaces: wooden furniture, metal shelves, wall mounts, or floors. This adaptability results from the design of the Tenderfeet, whose isolation effect remains consistent regardless of the support’s nature, provided it offers sufficient stability.

Operating principle and measurable acoustic benefits

The Iso Base operates through several complementary mechanisms to mitigate vibrational disturbances. Structural vibrations from the support are first attenuated by the impedance discontinuity created by the Tenderfeet points. Residual vibrations that reach the PMMA slab are then dissipated through the material’s internal damping.

Polymethyl methacrylate exhibits an internal loss factor that converts vibrational energy into heat—imperceptible yet effective for eliminating resonances. This dissipation occurs progressively and uniformly throughout the material’s mass, avoiding the localized resonance peaks characteristic of undamped metal structures.

Users typically report improved sonic definition, especially noticeable in the rendering of micro-details and the spatial ambiance of recordings. Reducing the sonic veil caused by micro-vibrations enables better instrument separation and a more stable, precise soundstage. Low frequencies gain articulation, shedding the muddiness that parasitic resonances can induce.

Technical Specifications

Compatibility

• Compatible with Gyro SE and Orbe SE models

Materials and Finish

• Base with feet
• Transparent polymethyl methacrylate (Plexiglas) finish