Biamp Launch custom speaker tuning

Defining your sound

Biamp Launch tuning uses a default target room tuning which has been tested and determined to yield excellent results in most conference room scenarios. There may be cases where users would prefer a modified tone. The custom room target file offers that solution.

To determine a target tone you wish to employ requires testing and comparative listening tests. An organization may have a particular sonic profile that they prefer to implement. The custom tuning file simplifies this with Launch automation.

A target value is applied and Launch measures each loudspeaker's response and applies a custom solution to that loudspeaker. The response curve and target SPL match for the room are achieved through a combination of amplitude and EQ adjustments based on measurements taken though the Parle microphones, which are operating in a special omnidirectional tuning mode. Biamp engineers know the precise response behaviors of the Parle mics which allows a high degree of accuracy (and repeatability) when performing room analysis and tuning. 

Here is an example of a speaker after Launch auto-tuning has adjusted gain and EQ to attempt to match the target room tuning curve and target SPL. Notice that the low frequency cutoff of the loudspeaker doesn't allow it to match the target below 100Hz, this is a physical property of the loudspeaker's frequency response. 

Acoustic measurements can be used to profile the desired sound of a room and a target curve can be defined based on the results. 

If there is a room which sounds particularly good then that's a great location to start taking measurements. A room that is difficult to get sounding nice and which poses odd acoustic challenges is not the best choice for refining your target response curve. 

How long will it take to get appropriate measurements? This is totally up to you. The first few times it will be a long process, but as you define a workflow and get a feel for what you are trying to see the process will speed up. Once you have defined a target custom room tuning it can be applied again and again and should yield consistent results from room to room.

It is important to remember that a room tuning target is not a guarantee of performance or meeting the target response curve - it is a goal that we try to achieve. Every room is different. Acoustic responses of similarly sized rooms vary widely due to many variables including the materials used in construction, furnishings, the ratio of hard to soft surfaces, HVAC noise, environmental noise, loudspeaker position, mic position, and more.

Target file parameters

A JSON file can be edited and uploaded for the desired custom tuning target. A template file can be found here: customTargetResponseTemplate.json

The JSON file allows you to modify the target low corner, high corner, and up to 10 parametric curves. Any of the frequencies, gains, or bandwidths can be changed. Any unused parametric curves can be deleted or left with default values.

Frequencies are adjustable from 20 to 20,000, bandwidth is adjustable from 0.1 to 4.0, gain is adjustable -30 to +15, same as the defaults for our parametric EQ block. 

A 12-channel Uber filter in Tesira software can be used to visualize the settings in the JSON file, using 2nd order Butterworth filters for the lower and upper corner settings. 

Application

To apply a new custom speaker tuning open the web browser-based user interface (web UI) of the TesiraFORTE X or Devio SCX. 

On the Audio webpage, click the Custom Speaker Tuning button in the Room Controls section.

A new Custom Speaker Tuning section will appear. 

Click the Select File button and choose a JSON file with the new target curve, then click the Apply button.

Launch configuration must now be run to apply the target settings.

Run Launch using the Launch Required button in the Room Controls section to tune the speakers using the new custom speaker tuning target file.

If a different target curve is desired click the Remove File button and confirm your intent remove the file.

If the Active Tuning File field is left empty the default Launch target will be used, or you may select and apply another JSON file.

Run Launch again using the Launch Required button to apply the new tuning. 

JSON template

Frequencies are adjustable from 20 to 20,000, bandwidth is adjustable from 0.1 to 4.0, gain is adjustable -30 to +15, same as the defaults for our parametric EQ block. A 12-channel Uber filter in Tesira software can be used to visualize the settings in the JSON file, using 2nd order Butterworth filters for the lower and upper corner settings. The Transfer Function block allows easy comparison of different filters.

{
    "lowerCorner":80.0,
    "upperCorner":16000.0,
    "parametricEQs":
    [
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        },
        {
        "freq": 500.0,
        "gain": 0.0,
        "bandwidth": 0.5
        }
    ]
}