Our real-time acoustic monitoring buoy MOBI

Discover our real-time acoustic monitoring buoy MOBI


MOBI is a buoy dedicated to real-time monitoring of underwater acoustic sounds. High acoustic performance is available with 24 bits raw data, 110 dB dynamic range, listening up to 200 kHz and self-noise below sea state zero. While recording, an embedded analysis is carried out to allow the real-time transmission of acoustic levels and alerts in the event of a threshold being exceeded. With a long data transmission range without additional subscription costs, energy self-sufficiency and a large storage capacity of up to 16 TB, MOBI is suitable for coastal or deep sea applications, for short missions or long-term PAM (Passive Acoustic Monitoring).


All included affordable buoy!

3 Solar panels, Saint Andrew Cross, 3 Radar reflectors, 3 Flashers, GPS, 3G/4G Module, Hydrophone, Rechargeable battery with charger, Storage, DaViS software, Accessory kit

Key specifications of our acoustic monitoring buoy

✓ Real-time embedded acoustic analysis

✓ Transmission of acoustic levels, alerts or raw data samples

✓ Large data transmission range > 23 km without additional subscription fees

✓ Internal raw data storage up to 16 TB

✓ Energy self-sufficent for long-term deployments

✓ Lightweight but rugged

✓ User-friendly

✓ Easy to transport and to deploy from small boats

✓ Configuration and remote software updates over WiFi or radio link (off-shore)

User-friendly buoy

MOBI has all the user-friendly advantages of the DORI recorder. No cables are needed for the configuration. You can use your smartphone or a laptop to access the configuration directly at sea over WiFi without opening it. To start recording, nothing easier! No cables or magnets are needed, just turn on the switch to REC position. Last recording configuration is automatically used.

MOBI features a lockable, quick and easy access to SD and SIM cards without any contact with the electronics, allowing memory swapping directly at sea.


MOBI buoy benefits from the high acoustic performance of the DORI range of underwater acoustic recorders with 24 bits recording,  a dynamic range of 110 dB and a maximum hearing frequency of 200 kHz. The raw acoustic data is stored internally on micro SD cards with a large capacity of up to 16 TB. The target frequency range is divided into two categories:

    • Low Frequency LF, with an HTI-96-MIN Low noise hydrophone: 2 Hz – 30 kHz
    • High Frequency HF, with an HTI-99-UHF Low noise hydrophone: 2 Hz – 250 kHz (allows click detection from marine mammals including the harbor porpoise).

MOBI allows listening to any underwater sound, such as biological sounds ranging from shrimp snapping, fish noises to marine mammals vocalizations and clicks, as well as human sounds from ship noises to offshore works. With self-noise below sea state zero and high dynamic range, ambient noise and weather noise can be monitored together with high-level sources.

Field advantages

Easy to transport

The foldable mast makes it a compact buoy for transport with a height of 1.66 m. A specific secured storage location for the hydrophone has been designed in the buoy to avoid any shock during transport. The hydrophone also has its own protective cage.

Easy to deploy

With its lightweight of 54 kg and its handles, the MOBI buoy can be easily deployed by 2 people from a small boat. The 3 lifting points allow easy recovery with a crane.

Maintenance in minutes !

Customers can carry out first level maintenance by themselves even at sea. The flasher, solar panels, radar reflectors, batteries and the mast can be replaced in few minutes.

Acoustic analysis

Several types of acoustic analyzes are available on pulsed events and their cumulative noise or on continuous sounds: the estimation of Sound Pressure Level (SPL) or Sound Exposure Level (SEL) following  ISO, 2017 standards, Third octave band levels following ANSI/ASA S1.11-2014, M-weighting levels (Southall et al. 2019).

The evaluation of acoustic features and normative thresholds exceedings is in accordance with regulations, in particular European recommendations (MSFD), French recommendations, American regulations (NMFS) and German regulations.

Full technical specifications of MOBI buoy

The table below shows in details the technical specifications of MOBI buoy.

Configuration WiFi or COM link (off-shore)
Recording mode Continuous or duty cycling
Scheduled mode Immediate or scheduled start
Storage Acoustic data : raw data [.wav] with selectable file duration
Pulse, continuous and cumulative analyze: SPL, Third octave band levels, M-weighting levels
Normative threshold exceeding
Marine mammals detection (future option)
Software update Remote update over WiFi or DATA link (off-shore)
Localization GPS included, mooring failure alerts


ADC 24 Bits
Dynamic range 110 dB
Analog gain 0 dB or 12 dB (Software configurable)
Analog high pass
10 Hz or 370 Hz (Software configurable)
Sampling rates LF : 31.25 kSps, 62.5 kSps, 125 kSps
HF : 31.25 kSps, 62.5 kSps, 125 kSps, 250 kSps, 360.36 kSps, 400 kSps
RTC accuracy 1 ppm


Power & autonomy
Battery Rechargeable lead battery
Battery charger Included
External sources 3 solar panels
Autonomy with
solar panels
Infinite, even in low light conditions
Complete darkness
About 10 days


Memory (Internal micro SD Card)
16 TB


Data transmission

Frequency 868 / 915 MHz 2.4 GHz
Acoustic data transmitted
Acoustic features X
Alerts X
Raw data samples X
Range to station
Buoy to shore (alt. 6m) > 23 km > 23 km Depends
on location
Buoy to boat (alt. 6m)
11 km 5 km
Buoy to buoy (used as relay buoys)
8 km 3.5 km X
Low frequency [LF] Hydrophone HTI-96-MIN Low noise
Analog bandwidth : 2 Hz – 30 kHz
High frequency [HF] Hydrophone HTI-99-UHF Low noise
Analog bandwidth : 2 Hz – 250 kHz
SH for LF & HF Standard : -185 dB re 1V/μPa,
other on request
Connection Remote with Subconn connector


Full volume 100 L
Diameter 650 mm
Folded height 1.66 m
Unfolded height 2.84 m
Height above water 2.17 m
Rugged buoy
Float robustness
PEHD UV15 foam filled
Waterproof level
IP68 extended up to 2.5 m depth
Marking, visibiliy and safety at sea Saint Andrew Cross, 3 Radar reflectors and 3 Flashers meeting the IALA standard and visible at 2 NM
Maintenance Easy by customer in less than : 5 min (flashers, solar panels, radar reflectors) / 20 min (batteries and mast with antennas)