Townshend Seismic Isolation Bars for Speakers and Subwoofers

Townshend Seismic Isolation Bars are designed to isolate loudspeakers and subwoofers from the floor, reducing the transmission of mechanical vibration between the speaker, the building structure and the listening room.

A loudspeaker does not operate independently of the surface beneath it. As the drivers and cabinet move, mechanical energy can pass into the floor. At the same time, vibration within the floor can travel back into the loudspeaker system.

Townshend Seismic Isolation addresses this mechanical connection directly.

Why isolate a loudspeaker from the floor?

A conventional loudspeaker placed directly on spikes, feet or a rigid stand is mechanically connected to the floor. This allows vibration to travel between the loudspeaker and the building structure.

The Seismic Isolation Bars replace that rigid connection with Townshend’s highly compliant Seismic Load Cells™.

Each speaker sits on two Bars, with two Load Cells per Bar. Together they provide compliant isolation in multiple directions while maintaining a stable platform for the loudspeaker.

The intention is simple: allow the loudspeaker to reproduce the recording without asking the floor to become part of the loudspeaker system.

Seismic isolation from approximately 3 Hz

The Seismic Load Cell system has a very low natural resonance, around 3 Hz when correctly loaded.

Above the isolation system’s resonant region, the transmission of mechanical vibration between the loudspeaker and supporting structure is progressively reduced.

This is fundamentally different from simply placing a soft pad underneath a speaker. The spring and damping characteristics of the Load Cells are engineered specifically for vibration isolation.

What can you hear?

Reducing the mechanical interaction between the loudspeaker and floor can make changes throughout the audible range.

Depending on the loudspeaker, floor construction and room, listeners may hear:

• tighter, better-defined bass
• improved clarity through the midrange
• greater separation between instruments
• more stable stereo imaging
• increased low-level detail
• a more open and natural presentation
• reduced vibration travelling through floors and adjoining rooms

The objective is not to change the tonal character of the loudspeaker. It is to reduce an unwanted mechanical influence on its performance.

Seismic Load Cells™

At the heart of every Townshend Seismic Isolation Bar is the Seismic Load Cell™.

Each Load Cell combines a carefully engineered spring system with damping and is selected according to the weight it needs to support.

Correct loading is important. A Load Cell that is significantly too stiff for the loudspeaker cannot operate in its intended range, while an overloaded cell may not provide sufficient movement or stability.

For this reason, Townshend offers different Load Cell capacities to suit loudspeakers and subwoofers of different weights.

Designed for many types of loudspeaker

Townshend Seismic Isolation Bars can be used beneath:

• floorstanding loudspeakers
• stand-mounted loudspeakers and their stands
• subwoofers
• large monitor systems
• many unconventional loudspeaker designs

The two independent Bars can be positioned to suit the footprint of the equipment, making them particularly useful where a fixed platform is unnecessary.

Bars or Seismic Podiums?

Both products use Townshend Seismic Load Cell technology, but their physical formats suit different applications.

Seismic Isolation Bars provide a simple and adaptable solution beneath a wide range of speakers and subwoofers.

Seismic Podiums provide a complete platform and can be preferable for particularly large, heavy or tall loudspeakers, or where the additional physical support of a platform is desirable.

If you are unsure which solution or Load Cell capacity is appropriate, contact Townshend Audio with the weight and dimensions of your loudspeakers.

Easy installation and adjustment

Installation requires no modification to the loudspeaker.

Place one Seismic Bar towards the front and one towards the rear of the speaker, position the Load Cells appropriately beneath the cabinet or base, and adjust the system until the loudspeaker is level and correctly supported.

Once installed, the loudspeaker should be able to move very slightly when gently pushed. This movement is normal and demonstrates the compliance that allows the isolation system to work.

Engineered by Townshend Audio

Townshend’s work on vibration isolation grew directly from designing high-performance audio systems.

We didn’t become experts in isolation by making isolation. We became experts in isolation by designing better audio systems.

Again and again, unwanted mechanical vibration proved to be a limitation. Seismic Isolation was developed to address that problem at its source.

The same underlying principle is now used throughout the Townshend Seismic Isolation range for loudspeakers, subwoofers, turntables and audio electronics.

Key Features

Technology: Townshend Seismic Load Cells™
Isolation: Low-frequency compliant mechanical isolation
System resonance: Approximately 3 Hz when correctly loaded
Configuration: Two Bars per loudspeaker, with two Load Cells per Bar
Adjustment: Levelling adjustment for accurate installation
Applications: Loudspeakers, speaker stands and subwoofers
Load capacity: Multiple Load Cell ratings available according to equipment weight
Construction: Engineered metal Bar structure with replaceable Load Cells
Made in: United Kingdom
Warranty: 5 years

Hear the loudspeaker, not the floor

The principle behind the Townshend Seismic Isolation Bars is straightforward.

Your loudspeaker should reproduce the music. Your floor shouldn’t.

By reducing the mechanical connection between the two, Seismic Isolation allows the loudspeaker and room to behave more independently, revealing more of the performance already available from your system.

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