This record describes scientific split-beam echosounder data collected on the RV Investigator voyage, IN2015_E05, which departed Hobart 2015-05-01 and returned on 2015-05-05. The Simrad EK60 split beam echosounders, 18, 38, 70 120, 200 and 333 kHz were used to acquire data. All frequencies were logged for the extent of the voyage. KSync settings were tested for interference with all the ship board acoustic instruments. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 66 files totalling 785 MB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_E01, 'Sea Trials and Calibrations' which departed Fremantle on the 06/01/2023 and returned to Fremantle on the 12/01/2023 (UTC). The Simrad EK60 split beam echosounders for18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of [range] m, around offshore Perth. All frequencies were logged continuously for the extent of the voyage. The frequencies were set to passive for the whole o the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 106 files totalling 519 MB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2019_E01, 'Post-Dry Dock Calibration Trials', which departed Singapore on the 19th July 2019 and returned to Cairns] on the 2nd August 2019. EK60 Calibration data was also collected on this voyage The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, within Australia's EEZ in the Arafura sea, the Torres Strait and the Coral Sea. All frequencies were logged continuously for the extent of the voyage within Australia's EEZ. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 173 files totalling 15.9 GB of raw data in this dataset. Processing has been conducted on the calibration data only. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_V04, International nutrient inter-comparison Voyage (INIV) which departed Hobart on the 05/06/23 and returned to Hobart on the 18/06/23. The Simrad EK60 split beam echosounders for18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, in the Southern Ocean Southwest of Hobart. All frequencies were logged sporadically for the extent of the voyage. The 70 KHz frequency was set to passive for the periods of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 2,644 files totalling 59.6 GB of raw data in this dataset. No Processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2015_T01, which departed Hobart 2015-05-10 and arrived Sydney on 2015-05-13. This voyage was a three-day transit from Hobart to Sydney. There were no science personnel onboard, however some opportunistic bathymetric survey was undertaken in addition to a deployment of the Continuous Plankton Recorder. The Simrad EK60 split beam echosounder was turned on sporadically. No processing or QC has been conducted on this data. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 610 files totalling 14.8 GB of raw data in this dataset. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2018_E01, Triaxus Sea Acceptance Testing & Calibrations Voyage, which departed Hobart on the 9th June 2018 and returned to Hobart on the 11th June 2018. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 50 m, at the calibration site at White Rock in Storm Bay. Sphere calibrations were performed during this voyage using a 60 mm copper sphere (18, 38, 70 kHz) and 38.1 mm Tungsten Carbide sphere (120, 200, 33kHz). All frequencies were logged for the extent of the calibrations of the voyage. Data are stored in .raw, .bot and .idx format at CSIRO. There are 21 .raw files totalling 422 MB of raw data in this dataset. On-axis calibration processing using EchoView 8 has been conducted on this data. Additional information regarding this dataset is contained in the GSM in2018_e01 EK60 Calibration Report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2023_V07, [FOCUS] which departed Hobart on the 15/11/23 and returned to Hobart on the 20/12/23. The Simrad EK60 split beam echosounders for18kHz and Simrad EK80 split beam echosounders for 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, around the Antarctic Circumpolar Current in the Southern Ocean, South of Hobart. All frequencies were logged continuously for the extent of the voyage. The 33 KHz and 70 KHz frequencies were set to passive for periods of the voyage. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1806 files totalling 176 GB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator gear trial IN2015_E04, which departed Hobart 2015-04-25 and returned on 2015-04-28. The Simrad EK60 split beam echosounders, 18, 38, 70 120, 200 and 333 kHz were used to test acoustic interference. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 39 files totalling 1.8 GB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator voyage IN2017_E04, Trials voayge, which departed Hobart on the 7th of December 2017and returned to Hobart on the 11th of December 2017. The Simrad EK60 split beam echosounders 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data to a range of 1500 m, off the southeast coast of Tasmania. All frequencies were logged continuously for the extent of the voyage. Data are stored in .raw, .bot and .idx format at CSIRO. There are 94 .raw files totalling 7.95 GB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.

This record describes scientific split-beam echosounder data collected on the RV Investigator sea trial IN2015_E06, which consisted of three legs, 5-8 Oct 2015, 9-11 Oct 2015 and 12-16 Oct 2015, in and out of Hobart. The Simrad EK60 split beam echosounders, 18, 38, 70 120, 200 and 333 kHz were used to acquire acoustic backscatter data. All frequencies were logged for the extent of the voyage. Sounder calibrations were undertaken. Data are stored in .raw, .bot and *.idx format at CSIRO. There are 1457 files totalling 25.3 GB of raw data in this dataset. No processing has been conducted on this data. Additional information regarding this dataset is contained in the GSM data acquisition and processing report. Additional data products may be available on request.