Starting Up:

An employee of the company ACOUSTICON GmbH, normally performs the ACAM System start-up. It includes the installation of the ACAM software, the final calibration of the free field loudspeakers (to the local conditions), and a final functional check of the ACAM System.

We strongly recommend reading this manual to avoid any possible operational errors. If you are not familiar with special functions of ACAM System, please contact us. The ACAM System is guaranteed to function correctly only when the technical requirements are fulfilled. Only an ACOUSTICON service technician should install the ACAM System on additional computers, to ensure proper calibration.

The electronic components of the ACAM System may not be exposed to an ambient room temperatures of more than 45°C. If the control unit is not sufficiently ventilated, the temperature may be exceeded and malfunction may occur. To ensure adequate ventilation, the control unit should be placed in a horizontal position. If you put the ACAM System in an enclosed space, please ensure that there is sufficient ventilation.

General:

The ACAM System was designed for the Windows XP Professional operating system and for compatibility with the NOAH 3 System. We cannot guarantee the ACAM Systems performance with other operating systems or other versions of NOAH. It is recommended that unnecessary programs not be installed on the ACAM System computer. These programs may result in interference with the ACAM System operations. These include software firewalls, additional network cards, special virus scanners, and computationally intensive screen savers.

Maintenance and Service:

The ACAM System should be tested at regular time intervals to ensure that all functions work correctly, and to ensure accuracy of measurement. At regular intervals, the ACAM System will display a message advising you of this requirement. Device functions from the form provided by ACOUSTICON need to be checked routinely. A safety-related and calibration check should be performed annually by ACOUSTICON. These items should be logged in the Medical Device Maintenance Book, ACOUSTICON will need this information to perform the annual calibration checks.

No special maintenance is required. All parts of the ACAM System may be cleaned using commercial detergents; special detergents are not required.

It is recommended to leave the ACAM System on continuously throughout the day, as opposed to frequently switching the control unit on and off. For the best balance between wear and energy conservation, switch the control unit on in the morning and off in the evening.

Updates:

Approximately two times per year, ACOUSTICON provides software updates. If you have negotiated a service contract with ACOUSTICON, new program versions are sent via mail. Installation updates should be performed at a convenient time when ACOUSTICON live support is available. Using the internet, ACOUSTICON can quickly and easily help you remotely. Please refer to the section: "Installation".

Operational Problems and Errors:

In the case of an operating error, please call our support hotline at +49 6162 - 9324 - 45. The ACOUSTICON support staff will address the problem and determine if it is a user error or a system error. Using the internet, ACOUSTICON can quickly and easily help you remotely. Please refer to the section: "Troubleshooting".

Communication with NOAH:

Data is saved in NOAH using an interface provided by NOAH. The ACAM System transfers and receives data from this interface. A request must be made to NOAH to receive the data. NOAH does not provide all of the data that is required to operate the ACAM System.

Instructions for Test Box Measurement:

Using the ACAM System you can measure the hearing instrument performance functions. This depends on the test box and the microphones used. The electronics provided offer a measuring dynamic of more than 130 dB. Deviations are ± 0.2 dB in a level range from 50 dB to 130 dB over the complete frequency range. The microphones provided  are electret microphones and have a sufficient transfer function for performing hearing instrument and real ear measurements with the accuracy required by the IEC standards. The microphone sensitivity can decrease with continuous use of the ACAM System. The microphone function can be checked as described below.

Microphone Sensitivity Check:

The displayed sound pressure level of the microphones should match the actual sound pressure level generated in the test box coupler. It is necessary to generate this defined sound pressure level using a calibrated sound source. The microphones used in the ACAM System have a diameter which is compatible with a Brüel & Kjaer calibration sound source (pistonphone or calibrator using a ½ " adapter). Other calibration sound sources may also be used.

Microphone Frequency Linearity Check:

Perform an input/output (i/o) measurement with the control microphone at an input level from 40 dB to 100 dB. If the curve does not show an angle of exactly 45°, one of the microphones may be defective. First perform a test box calibration. If the result is abnormal, both microphones should be returned to ACOUSTICON for troubleshooting. You will find additional instructions for calibrating the test box in the "ACAM System Help Text."

Microphone Dynamic Linearity Check:

Perform an input/output (i/o) measurement with the control microphone at an input level from 40 dB to 100 dB. If the curve does not show an angle of exactly 45°, one of the microphones may be defective. First perform a test box calibration. If the result is abnormal, both microphones should be returned to ACOUSTICON for troubleshooting. You will find additional instructions for calibrating the test box in the "ACAM System Help Text."

Measuring Room Requirements:

It is necessary to perform hearing instrument measures in a quiet room to ensure reliable results. Noise interference levels in the environment should not be greater than 10 dB lower than the lowest input sound pressure level used for measurements. If you want to measure at a 40 dB intensity level, the noise levels in the measuring room should not exceed 30 dB. Use an activated induction coil to run a frequency sweep; this will allow you to check the noise level of your ACAM test box. If these standards are not met, the available measuring range will be limited.

When measuring the equivalent input noise of a hearing instrument, the noise tolerance has to be 10 dB below the estimated equivalent input noise of the hearing instrument. The equivalent input noise of a hearing instrument is usually between 20 dB and 40 dB; meaning that interfering noise can be at a maximum of 10 dB in order to accurately measure the equivalent input noise. If a very high input noise is measured from the environment, this could be interfering noise that is amplified by the hearing instrument.

Test Box Upgrade and Change:

If you want to perform measurements according to the IEC 118-0 Standard, an ear simulator is required according to the IEC 711 standard. Currently, this ear simulator is only offered by Brüel & Kjaer and is very costly. A reasonable alternative to the ear simulator is offered by Professor Keller with his Simulated Ear Simulator coupler (SES). The SES coupler closely matches the data of the Bruel & Kjaer ear simulator (± 2 dB) and allows a way to approximately verify the measuring data obtained with the ear simulator. You may obtain the SES coupler from ACOUSTICON and add it to the ACAM System.

It is possible to connect other ear simulators, other microphones or additional test chambers to the ACAM System. Appropriate microphone adapters will be provided by ACOUSTICON for use with Brüel & Kjaer equipment. Contact ACOUSTICON to determine if different transducers will be compatible with the ACAM System.