The following application is  extracted from the Dirac live quick start guide for Dirac VST plugin. Note that these instructions only apply for customers using the ProAudio version of Dirac Live using VST plugin. This application is specific and can only be used with Digital Audio Workstations (e.g. ProTools/Cubase/Reaper) in a recording studio setting. For all standard applications of Dirac Live, please refer to our Dirac Live products such as DDRC and SHD series.

In order to use Dirac Live for Studio, you will need to download and install two different components: the Dirac Live calibration tool (desktop software) and the Dirac Live audio plugin(VST plugin). The calibration tool is used to measure and generate filters while the audio plugin stores the corresponding filters and processes audio data. The UMIK-1 or UMIK-2 (Reference Grade Microphone) will be used through out this application note.

1. Download Dirac Live VST plugin

You can download the audio plugin Dirac Live processor here.

The plugin will be placed in a folder according to the path below, unless you have made changes during the installation process:

  • Windows
    Program Files/Common Files/VST2
    Program Files/Common Files/VST3
    Program Files/Common Files/Avid/Audio/Plug-Ins
  •  MacOS
    /Library/Audio/Plug-Ins/Components
    /Library/Audio/Plug-Ins/VST
    /Library/Audio/Plug-Ins/VST3
    /Library/Application Support/Avid/Audio/Plug-Ins

Start your DAW and locate the audio plugin in the plugin menu. You might need to go through additional steps to activate the plugin, depending on your DAW.

There will be no filter stored in the audio plugin unless you have previously created new filters with the calibration tool.

Press the “play” button in your DAW to ensure that the audio stream is active while connected with the calibration tool. It is important that the audio stream is active during the whole calibration process.Here is a 30 minutes mp3that you can use.

2. Install and set up the Dirac Live calibration tool

You can download the Dirac Live calibration tool (desktop software version)here. Make sure that your computer is connected to the internet for licensing purposes.

  • Please see to that your UMIK-1/UMIK-2 microphone is connected to the computer running Dirac Live.
  • Enter your account details in the first screen after launching Dirac Live. Login is required in order to save/restore any project or use purchased features.

3. Select your device

  • Dirac Live will start with scanning the network for compatible devices that will store the filters and process audio data (such as AVRs or the Dirac Live processor audio plugin). You can click the “Rescan devices” icon in the upper left corner if you want to refresh the scanning result.

Please select “Dirac Live processor” and proceed. Do not select any AVRs, because in this case, the Dirac Live audio plugin will function as the device that stores the filters.

4. Select the UMIK-1/UMIK-2 as your recording device

  • The UMIK-1/2 will now appear as an interface inside the GUI.
  • If you haven't done so already, now is the time to grab the unique calibration file for your microphone. Use the serial number on the body of the microphone to download the files from the UMIK-1/UMIK-2 product page.

download cal

We provide two calibration files to be used depending on your application.

- For stereo system (e.g. 2ch dirac live, single speaker measurement), use the 0deg file and point the UMIK at the speakers
- For multichannel system (E.g. 5.1/7.1) or a surround application where multiple speakers are spreadout around the room, use the 90deg file and point the UMIK at the ceiling.

  • You can load your microphone calibration file (.txt) by pressing the button “No microphone calibration” and selecting “Load from file”.
  • Select the calibration microphone that is connected to your computer.

5. Volume calibration

  • In this step we will set up the output volume of each speaker to make sure that the playback volume of all speakers is at an appropriate level. This is an important step, as too low or high volume can result in poor or failed measurements, and excessive volume could potentially damage the speakers.
  • It is sufficient that the speakers are approximately within a reasonable range, that is to say, the volume does not have to be at an exact level, since the calibration tool will automatically adjust it.

  1. Place the microphone in the middle of the listening area.
  2. Make sure the master output level is at a low value.
  3. Select a speaker, for instance, front left, and press the “play” button for that speaker. You should now see a sign above the play/stop button that indicates the recording level. If you slowly increase the master output level, you should see the level bar for the selected speaker increases. If not, go back and check the microphone connection.
  4. Increase the master output until either the level bar for the selected speaker is in the green area, or the output level is loud enough at a comfortable level.
  5. When the above process is completed, the level bars for all speakers should indicate roughly the same value within 15dB.

6. Select arrangement

There are three options available, please select “Studio”.

7. Measure

  • Make sure there is a clear line-of-sight between the microphone and speaker.
  • Make sure that there is no background noise (tv, radio, AC, etc.) while doing the measurements.
  •  Remember to keep the microphone still, preferably using a stand or similar.
  • A sweep will be played in turn through each speaker and a final sweep will be played through the first speaker once more.
  • The main measurement position: This is where you head is most likely to be, and it is the most important position to be measured correctly.
  • Spacing and order: In general, the measurement positions should be 40 – 60 cm apart, however the exact placement or order of the remaining positions is not crucial, and the position layout only provides a rough guide for you.
  • Number of measurements: You can do fewer measurements than the full set before proceeding to Filter Design, but we recommend that you complete the full set for the best possible audio optimisation results.
  • Your project will be automatically saved, however, we strongly recommend that you always manually save the project as well. To save the project, please select “Save project” in the hamburger menu (upper left corner).


8. Filter Design

After completing the measurements, Dirac Live will automatically generate suggested target curve(s) for frequency response and the corresponding correction filters that are intended to enhance your sound system as much as possible. You can make fine adjustments to your preferences. The frequency response correction will be performed in real time so that you can see the correction result immediately and continuously make more adjustments.

  • Add/delete control points by right clicking on the curve
  • Modify the curve by dragging the control points
  • Modify the frequency range that Dirac Live will compensate by dragging the curtains (left/right). The dotted lines indicate the automatically detected sound thresholds. Outside of these limits no correction will be applied, i.e. the audio signal will not be adjusted in the frequency area on either side of the curtains (shadowed area).
  • Custom target curves (.txt or. targetcurve format) can be loaded, see option in the hamburger menu (top left).
  • With the “Take snapshot” function, you can create a snapshot of the current state – if you make any changes to a target curve, it is possible to switch between different snapshots, without having to save/load projects.
  • Zoom in/out by using pinch zoom on a touchpad or scroll wheel with a desktop mouse, panning can be achieved by hold+drag.
  • Select different display options to your preference in the lower right corner.

9. Filter export

The last step is to export the filter for a listening test. Select a slot and save under the desired name (there may be an auto-generated name, which can be replaced). When export is complete, the application will return to the Filter Design view. Remember to save your project before exiting the application.

After the filter is exported, the filter will automatically appear in the audio plugin. No other actions are needed to apply the filter to your audio stream.

Dirac Live audio processing is now happening behind the scenes on your DAW.  Enjoy!!

 

10. Wrapping Up

Hoping this application note will showcase how the Dirac Live VST plugin can be used together with UMIK-1 or UMIK-2. For futher information, please make sure to read the quick start guide  and additional content on the product page. Dirac Research's technical support can be joined here.

 


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