Using external speakers with Nureva conferencing systems

Nureva^® audio systems provide high-quality microphone pickup and speaker output in a variety of room types. Each conferencing system is designed for a specified maximum room size. However, there are two scenarios in which external speakers could be needed.

1. A preferred speaker system is already installed in the room.

2. A room has high background noise and/or poor acoustics.

Note: If speaker output is a concern, the following support articles might also be helpful.

• Adjusting treble and bass settings to optimize speaker volume

• Adjust Nureva audio device speaker volume in system settings

Connecting external speakers

The HDL300, Dual HDL300, HDL310 and HDL410 audio conferencing systems can be used with external speakers. The output for the external speakers will be monaural (mono), despite any settings in Nureva Console or at the source of the signal.

1. Connect the external speaker system to the auxiliary output port on the connect module with a 3.5 mm stereo jack.

2. Set the auxiliary output port to the speaker-out mode in Nureva Console. The speaker-out mode routes the speaker signal to the external speakers and turns off the Nureva device’s built-in speakers.

   • Using the auxiliary ports on the HDL300 and Dual HDL300 systems

   • Using the auxiliary ports on an HDL310 system

   • Using the auxiliary ports on an HDL410 system

3. Perform a fast calibration with the Nureva audio conferencing system to configure the new setup.

   • How to calibrate the HDL300 system

   • How to calibrate the Dual HDL300 system

   • How to calibrate the HDL310 system

   • How to calibrate the HDL410 system

Important: There is only one auxiliary output port, so the connection to the device controlling the audio or video conference must be USB when the speaker-out mode is used.

Echo cancellation

When external speakers are connected to the auxiliary output port and the speaker-out mode is selected in Nureva Console, the Nureva device will echo-cancel the speaker signal to prevent remote participants from hearing an echo when they speak. However, the echo-canceling function of Nureva audio systems is optimized for the original speakers, so performance with external speakers may vary.

Considerations when using external speakers

Fixed gain

Ensure that the amplifier maintains a fixed gain. If the amplifier allows for variable gain, set it to a single value and avoid changing it — especially during amplifier use. Adjusting the gain externally using hardware could invalidate calibration settings and potentially degrade system performance. Adjust speaker volume through the application software or operating system.

Flat gain

The amplifier and speaker should have a reasonably flat gain over the voice band frequency (300 Hz to 7 kHz) for the best performance. Equalizers or speakers that result in unlevel gain will cause degradation in the echo cancellation performance.

Avoid bass-boosting

Avoid any bass-boosting amplification (in the 50 Hz to 300 Hz range) and any powerful bass speakers or equalization schemes, which will cause an uneven frequency response.

Positioning the external speakers

The external speakers should not be installed close to the microphone and speaker bar, nor should they be pointed in its direction. Direct coupling from the speakers to the microphones will cause issues with echo cancellation.

Calibrating with external speakers

After starting a fast recalibration with external speakers, the LED indicator on the microphone and speaker bars will flash for 15-20 seconds. The calibration signal coming from the external speaker system will only be heard for the first 7-10 seconds.

Using external speakers with the HDL410

HDL410 systems using firmware version 1.3.222752 or earlier will require special consideration when used with external speakers:

• During installation, the HDL410 runs through an extended calibration sequence that configures the echo canceler and determines the relative geometric location of each microphone and speaker bar. The calibration routine must be run through the built-in HDL410 speakers.

• A fast calibration should be performed on the HDL410 after it is installed but before connecting external speakers or setting the auxiliary output port to the speaker-out mode. Do not perform a fast calibration after external speakers have been connected or the auxiliary output port has been set to the speaker-out mode.