DAS Interrogators

DAS Interrogators

Treble+ DAS Interrogator

The Treble+ distributed acoustic sensing (DAS) interrogator's patented design leads the market with ultra-low instrument noise at acoustic frequencies and offers a longer range alternative to the Treble model.  These improvements broaden the possible applications without compromising on data quality.

The Treble+ interrogator is ideal for pipeline monitoring, micro-seismic monitoring, active seismic acquisition, earthquake monitoring and down-well monitoring.

Download the new datasheet to see in-depth performance figures and quantify the benefits of the Treble+.

Treble DAS Interrogator

The Treble interrogator provides a lower cost alternative to the Treble+, with excellent signal quality in shorter range applications and stronger motion situations, including perimeter security, detection of third party interference and industrial equipment monitoring.

Both Terra15 Distributed Acoustic Sensing (DAS) interrogators are based on our unique and patented architecture which provides low-noise, flexible and quantitative data throughout the active-seismic, passive-seismic and acoustic frequency bands.

This performance advantage in both the Treble and Treble+ is possible with instrument strain-noise that decreases with higher-frequency – a unique and worldwide industry first in distributed acoustic sensing.

Why Choose a Terra15 DAS Interrogator?

Affordability is a key advantage of the Treble and Treble+ models - optimised for permanent site installations

Flexibility provided by user defined application parameters, giving more control to the user over their data

Compatibility with many types of fiber, including multimode, single mode, and engineered fibers

Real time audio playback for enhanced situational awareness for users

User friendly operation and interactivity is a priority in the software provided to users

Patented true-phase and true-acoustic DAS technology offering the quality data required for quantitative measurements and accurate ML classifications

Lowest instrument strain-noise at higher frequencies associated with micro-seismic events, acoustic sound and higher resolution active seismic

Immune to polarisation fading and amplitude fading guaranteeing there will be no 'dead spots' along the cable

Highly stable response, sensitivity, and distributed sensing positions for precise monitoring

Gauge free (velocity) and Gauge applied (Strain-rate) acquisition modes

24/7 continuous operation and data streaming allowing permanent monitoring use cases

Open API to simplify and streamline integration for OEM customers

High Frequency Advantage

Unlike other interrogators, Terra15's interrogators natively measure rate of change of vibration on the sensing fiber. This means the more rapidly changing (or higher frequency) the source, the larger the measured signal relative to the system noise. Represented in strain-equivalent units, both Trebles have a system noise that decreases as frequency increases.

This unique advantage means that at audible frequencies and above, the Treble interrogators have market leading sensitivity.

Selectable Gauge or Gauge Free Data

The native velocity datatype does not require the user to define a gauge at the time of acquisition. This “gauge-free” operation results in a system that offers unrivalled flexibility and sensitivity. Sensitivity enhancement over native strain systems is especially noticeable for seismic waves arriving close to perpendicular (90°) to the fiber. Additionally the native velocity datatype may be directly compared against directional geophone data.

For applications where strain or strain-rate data are preferable, the interrogators allow the gauge length to be software defined in post-processing. This uniquely allows a variable gauge length to be applied for different frequency bands; fibre sections or times, resulting in optimal signal to noise enhancement.

Download & Compare Datasheets


Up to 40km

Up to 20km

Instrument self-noise



Ideal applications

Weak motion

Strong motion

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