Version: current

Adding equipment to inventory

In SAFE you need to define your equipment. You do this by adding your equipment to the inventory. This will ensure that your equipment parameters are specified and ready to use in all tests.

Inventory

There are several different types of equipment you can add:

  • Audio Interface: external and internal soundcard interfaces, bluetooth interfaces.
  • Microphones: specific for microphone capsules.
  • Active Loudspeakers: specific for loudspeakers with amplifiers.
  • Passive Loudspeakers: specific for loudspeakers without amplifiers.
  • Headphone: like a passive loudspeaker, but in a pair.
  • Power Amplifier: specific for amplifiers connected to a transducer such as a passive loudspeaker.

How to add equipment

To start adding equipment press the Local Inventory button in the Navigation Panel. The tool buttons at the top of the screen changes to inventory related buttons. Press the button corresponding to the type of equipment you want to add.

Inventory

Choose or input the manufacturer name, model name, internal number and serial number. Serial number is the only parameter which is not obligatory. When the obligatory parameters have been filled press Load parameters.

Parameters are specific to each type of equipment and are used to define the characteristics of that piece of equipment. For example a microphones sensitivity parameter is used to calibrate signals measured with that microphone.

You are able to share equipment usage with Encida, to help improve Encidas global database of equipment, expanding it with new equipment, monitoring calibration values and much more.

How to add an audio interface

The audio interface equipment type is what interfaces between a computer and sensors and transducers. This could be external interfaces such as USB or Firewire interfaces, Bluetooth interfaces between the computer and a headphone or the internal interface inside your computer.

important

External interfaces should be connected to the computer before starting SAFE.

important

Bluetooth devices should be connected via bluetooth before starting SAFE.

  1. Start by defining your equipment
  2. Specify the equipment parameters (see below)
  3. Hit save.

Driver

The driver refers to the audio driver that the audio device should be designated to. Different drivers can affect volume, latency etc. SAFE automatically finds the drivers that are available on your computer. Default is WASAPI.

tip

Use the ASIO driver for Windows. Find it here

On windows the drivers are:

  • ASIO: is made by Steinberg and communicates directly with external audio devices.
  • WASAPI: is the newest Windows driver.

Device Name

Based on your driver choice every device that is available for that driver will be shown. SAFE will automatically search for devices which are named after the manufacturer or model name.

When a device is chosen every input and output sample rate will be checked for compatibility. The number of input and output channels the device has, is shown below the device name.

If your device is not on the list, but is connected then you might not have installed a specific audio driver for that interface. See more under audio interface troubleshooting.

Interface type

You can define the interface type of your audio interface. You can choose between USB, Bluetooth and Onboard. Default is USB.

Default sample rate

Set the default sample rate of the audio interface. Default is 48000 Hz. When configuring the audio interface in a test, the sample rate can be changed.

Default block size

Set the default block size of the audio interface. Default is 256. When configuring the audio interface in a test, the block size can be changed. The block size impacts the latency of the interface.

Default bit resolution

The default bit resolution can currently only be 32 bit float.

Input channels

SAFE will automatically detect the number of input channels your audio interface has. However, the channels must be defined.

channels

This is due to some inputs having multiple types in one channel, leading to different calibration values or multiple digital channels with only one physical channel such as ADAT. You can choose between the following types:

caution

S/PDIF and ADAT are currently not supported

  • Microphone/Line
  • Microphone
  • Microphone/Hi-Z
  • Microphone/Line/Hi-Z
  • Line
  • S/PDIF
  • ADAT

Output channels

SAFE will automatically detect the number of output channels your audio interface has. However, the channels must be defined. This is due to some outputs having multiple types in one channel leading to different calibration values or multiple digital channels with only one physical channel such as ADAT. You can choose between the following types:

caution

S/PDIF and ADAT are currently not supported

  • Line
  • S/PDIF
  • ADAT
  • Headphone

How to add a microphone

The microphone equipment type is a sensor which converts sound pressure into an electrical signal. It can be connected to a preamplifier or an audio interface that supports it.

  1. Start by defining your equipment.
  2. Specify the equipment parameters (see below).
  3. Hit save.

Sensitivity

The sensitivity of a microphone describes the microphone's conversion ratio from sound pressure to voltage. Usually described as Pa/mV but can also be given as dB. The sensitivity is used to convert your measured data into Pascal.

tip

Microphones can be manually calibrated later, find out how here(insert link to how to calibrate)

How to add an active loudspeaker

The active loudspeaker equipment type is a loudspeaker which has an internal amplifier. It can be connected directly to an audio interface.

  1. Start by defining your equipment.
  2. Specify the equipment parameters (see below).
  3. Hit save.

Sensitivity

The sensitivity of an active loudspeaker describes the loudspeaker's conversion ratio from voltage to sound pressure level.

How to add a passive loudspeaker

The passive loudspeaker equipment type is a loudspeaker which has no amplifiers. It can be connected directly to an audio interface.

  1. Start by defining your equipment.
  2. Specify the equipment parameters (see below).
  3. Hit save.

Sensitivity

The sensitivity of an passive loudspeaker describes the loudspeaker's conversion ratio from voltage to sound pressure level. Usually described as SPL/V and is typically specified at 2.83 V at 1 m distance for an 8 Ohm speaker.

How to add headphones

The headphones equipment type refers to electroacoustic transducers (loudspeakers) that convert an electrical signal into a corresponding sound. These transducers are usually worn around or over the ears of a person. They can be directly connected to an audio interface, typically the headphone output for a better impedance match.

  1. Start by defining your equipment.
  2. Specify the equipment parameters (see below).
  3. Hit save.

Sensitivity

The sensitivity of the headphones describes the headphones' conversion ratio from voltage to sound pressure level.

How to add a power amplifier

A power amplifier is an electronic amplifier designed to increase the magnitude of power of a given input signal to a level high enough to drive the loads of output devices like speakers or headphones. A power amplifier is connected directly to an audio interface and to a speaker for output.

  1. Start by defining your equipment.
  2. Specify the equipment parameters (see below).
  3. Hit save.

Gain

The gain of a power amplifier is the voltage gain from input to output. Typically described in dB.

Channels

Channels is a specification of how many channels the power amplifier has. SAFE currently only supports N inputs, N outputs.