Hear Everything
in the Water Column.
Three complementary recording platforms for every passive acoustic monitoring mission — from a portable 4-channel broadband recorder to an autonomous seabed instrument that records continuously for up to 180 days unattended. Engineered in Brittany by RTsys, and compatible out of the box with PAMGuard and RT-Live Monitor.
One acoustic family for the entire monitoring brief
Passive acoustic monitoring rarely needs one instrument — it needs the right instrument for each job. A noise-impact survey wants four channels and high bandwidth at the source; a protected-species baseline wants months of unattended endurance; a noise-certification measurement wants a calibrated array on the seabed. RTsys covers all three from a single, interoperable product line.
- RESEA — 4-input broadband recorder for active, high-resolution survey work
- SYLENCE-LP — single-channel autonomous recorder for long unattended deployments
- TRIPOD — self-righting 4-hydrophone seabed frame for source localisation
The problems RTsys recorders were built to solve
Underwater sound is unforgiving to measure well. These are the constraints every PAM operator works against — and what RTsys engineered around.
🔁 Costly Revisits
Servicing a seabed instrument means a vessel, a crew and weather windows. Short endurance multiplies that cost across a survey.
📡 Huge Frequency Span
Baleen whale calls sit near 10 Hz; dolphin clicks exceed 100 kHz. Most recorders can't hold low-noise performance across both.
📋 Defensible Records
MMO/PSO and noise-certification work must produce calibrated, auditable data — not just an audio file an analyst has to fight with.
🧭 Where's the Source?
A single hydrophone hears a sound but can't locate it. Bearing and trajectory need a spatially separated array.
RESEA — the survey workhorse
RTsys' flagship stationary recorder: four simultaneous channels, up to 500 kHz bandwidth and more than 100 dB of dynamic range, in a case you can carry aboard.
Capture the whole soundscape, not a slice of it
With four hydrophone inputs sampled simultaneously and bandwidth reaching 500 kHz, the RESEA records the full acoustic environment in a single pass — low-frequency shipping and seismic energy alongside high-frequency odontocete echolocation clicks. A transportable-case version makes it equally at home on a research vessel or a quayside MMO station.
- Configurable hydrophone options for the frequency band you care about
- Native PAMGuard and RT-Live Monitor workflows — and open-source compatible
- Built for Marine Mammal Observer (MMO) and Protected Species Observer (PSO) work
RESEA Specifications ▾
| Hydrophone Inputs | 4 simultaneous channels |
| Bandwidth | Up to 500 kHz |
| Dynamic Range | >100 dB |
| Form Factor | Transportable case available |
| Software | RTsys suite · PAMGuard · RT-Live Monitor |
| Applications | MMO, PSO, ship noise, ambient monitoring |
SYLENCE-LP — leave it for six months
A single-channel autonomous recorder engineered for power efficiency, so it keeps recording long after a crewed survey would have packed up. Best value-for-money long-term recorder on the market.
Endurance where revisits are expensive or impossible
The SYLENCE-LP is purpose-built for unattended seabed deployments where visiting the site frequently is impractical. A single-channel design optimised for power lets the 44 cm unit record continuously for up to 180 days on internal batteries; a compact 22 cm unit covers shorter 35-day campaigns. Both take fixed or cabled hydrophones, and every recording drops straight into PAMGuard for species detection on recovery.
SYLENCE-LP Specifications ▾
| Hydrophone Inputs | 1 channel |
| Max Bandwidth | 256 kHz |
| Dynamic Range | >100 dB |
| Endurance (22 cm) | 35 days continuous |
| Endurance (44 cm) | 180 days continuous |
| Hydrophone Options | Fixed or cabled |
| Software | PAMGuard & RT-Live Monitor |
TRIPOD — locate the source, not just the sound
A lightweight, self-righting seabed frame carrying four hydrophones around an embedded RESEA — turning a recording into bearing, trajectory and 3D propagation data.
Spatial separation turns audio into geometry
The TRIPOD integrates four spatially separated hydrophones with an embedded RESEA broadband recorder. The separation is what enables trajectography — resolving the bearing and movement of a passing vessel — and full three-dimensional sound-propagation analysis. A self-righting landing mechanism guarantees the array sets up in the correct acoustic configuration, and the frame is light enough for one person to deploy from a small vessel.
- 4 integrated wide-band hydrophones with controlled spatial separation
- Embedded RESEA recorder — the survey-grade core, on the seabed
- Ideal for ship underwater radiated noise (URN) certification
- Self-righting landing · single-person deployable from small boats
TRIPOD Specifications ▾
| Hydrophones | 4 integrated wide-band |
| Recorder | Integrated RESEA unit |
| Deployment | Single person, small vessel |
| Landing | Self-righting seabed mechanism |
| Capability | Trajectography · 3D propagation analysis |
| Applications | Ship URN · MRE · marine biology · ambient noise |
See the data, not just the device
Every RTsys recorder feeds the same proven analysis workflow — PAMGuard for detection and classification, RT-Live Monitor for real-time mitigation. Below: real output from RTsys deployments.
A workflow your analysts already trust
RTsys recorders are natively compatible with PAMGuard — the open-source standard for passive acoustic detection and classification — so data lands in the tools your team already uses, with no conversion gymnastics. For live work, RT-Live Monitor streams detections in real time to drive noise-mitigation decisions on deck.
- Calibrated, auditable records for regulatory submission
- Real-time detection for MMO/PSO shutdown triggers
- Open-source compatible — no vendor lock-in on your data
Used by leading ocean-science institutions
Research institutes, hydrographic services and marine contractors run RTsys passive-acoustic systems on programmes worldwide.
Where RTsys recorders earn their keep
From a one-day MMO operation to a six-month unattended seabed baseline, the range covers the full breadth of passive acoustic monitoring.
Marine Mammal & PSO Monitoring
MMO/PSO operations with real-time detection for mitigation-zone shutdown triggers during noisy offshore activity.
Ship Underwater Radiated Noise
Calibrated URN certification measurements with the TRIPOD array — bearing, trajectory and source level.
Offshore Wind Baselines
Long unattended SYLENCE-LP deployments for pre-construction acoustic baselines and pile-driving impact studies.
Ambient Noise Monitoring
Long-term soundscape characterisation against MSFD and other regulatory descriptors of underwater noise.
Marine Biology & Bioacoustics
Fish and invertebrate vocalisation studies, cetacean population work and habitat soundscape research.
Acoustic Propagation Studies
Multi-hydrophone 3D propagation analysis for source localisation and environmental modelling.
Briefsheets & Software Suite
Official RTsys documentation for the acoustic recorder range and the SDA software suite — sourced directly from RTsys.
Request a Quote — Acoustic Recorders
Tell us about your monitoring requirements and we will recommend the right RTsys recorder configuration for your project.
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