TuneEQ
TuneEQ is a semi-automated, fully parametric equalizer that can adjust the frequency response measured in the RTA to the reference curve in the shortest possible time.
1.Starting the Real Time Analyzer
Click on the highlighted "RTA" button in the DSP PC-Tool.
If you operate the DSP PC-Tool in demo mode, the analyzer will not function. Only when you connect one of our DSP components to your computer will the Analyzer display its full range of functions and enable measurements.
The RTA now opens in an external window, which can be scaled to the desired size.
A view directly in the PC-Tool can also be selected. To do this, the RTA window must be set to "Embedded" in the DCM menu under PC-Tool Configuration.
2. Basic settings of the RTA for TuneEQ
You can access the basic settings of the RTA via the RTA Settings button.
The microphone connected via USB is displayed in the upper area.
You can also upload any existing calibration file for the microphone used.
In the middle section, you will find general setting options for smoothing, measurement time, resolution, style and color theme.
You can find more detailed explanations of the respective points in the explanation of the Real-Time Analyzer.
We would recommend adopting all settings as shown.
The cross at "Adjust Frequency Limits to selected Channel Filters" ensures that only those frequencies are automatically operated via TuneEQ that were previously selected as the usable frequency range of the respective loudspeaker via active crossovers.
The maximum deviation (Max Deviation) from the reference curve is set to 0.1 dB by default, so TuneEQ will try to achieve this. The maximum boost of a frequency is 6 dB.
Select the desired reference curve for setting the equalizer and the filters in the DSP here.
The "ATF" reference curve is always predefined as the default, as this curve is also used in the industry for the calibration of cars. Alternatively, you can select a linear (flat) reference curve. This curve should only be used for home applications and not for measurements in vehicles, as it will not lead to satisfactory acoustic results in the latter case.
If the ATF reference curve does not suit your taste, you can also define your own curve under "Custom". Each frequency band can be changed individually. Save a self-defined reference curve to your hard disk via "Save Reference Curve" so that you can load it again at a later time via "Load Reference Curve".
You can return to the RTA via the "Back" button.
After all the basic settings have been made, we come back to the actual RTA.
Additional fields are activated by selecting TuneEQ.
In the lower section, you can select which bands are to be used for TuneEQ. Bands 3 to 29 are selected by default. As band 1 is used as a low shelf, band 2 is required for tone control and band 30 could be used as a high shelf, these bands are often not used in TuneEQ.
If you do not want to use the shelf filters or Tone Control, you can of course use all 30 bands for TuneEQ.
You can also select the frequency from and up to which TuneEQ should operate. We get the default setting because "Adjust Frequency Limits to selected Channel Filters" was selected in the settings.
As soon as the "Channel Filter Target Mode" is activated, the active filter set for the selected channel is also displayed in the reference curve. In our case, we have selected the front mid-high channels A and B, which have a 220 Hz 24 dB Butterworth filter activated in the Main menu.
The reference curve can now be shifted in the high pass via the left horizontal slider . The number of Hertz by which the frequency has been shifted is displayed. However, this does not affect the set filter in any way!
The reference curve in the low-pass filter can also be shifted in the same way.
By right-clicking on this bar, the set value is immediately reset to zero.
3. Measurement
In order to achieve an optimum measurement result, it is essential that the sound pressure of the test signal is correct. The Real-Time Analyzer uses a colored bar at the top to indicate whether the pink noise level is sufficient for the measurement or not.
Green bar
All dB values between -30 dB and 0 dB are displayed as a green bar. In this case, the sound pressure level is sufficiently high for a measurement.
Orange bar
If the bar only moves to the middle of the display and lights up orange, the sound pressure level is too low; turn the volume up further on the car radio or check whether the sensitivity of the measuring microphone is set correctly in the control panel of your PC. In addition to the bar display, there is also a dB display at the top right of the display - all values below -30 dB are too low for a correct measurement.
Red bar
The sound pressure level is too high; reduce the volume on the car radio or check whether the sensitivity of the measuring microphone is set correctly in the control panel of your PC.
Overdriving the measurement will always lead to distorted results and should therefore be avoided at all costs.
We check the set volume by pressing "Start Analyzer".
Hold the measuring microphone vertically upwards and always move it slowly back and forth in a semicircle between your two ears when measuring!
The volume of the radio is now increased until the bar at the top turns green and all ambient noise is masked.
In our case, the level is specified as -12 dB, so the set volume is appropriate.
The red curve shows the current measured values of the measuring microphone. This display fluctuates quite strongly at low frequencies, making it difficult to read the amplitude response correctly.
We now start the TuneEQ measurement by pressing the "Start Measurement" box.
The measuring time is 20 seconds.
An "Attention!" window opens first with the following information:
We operate channels A (Front L Mid) and B (Front R Mid)
EQ bands 3 to 29 are selected and reset.
All selected tapes are always reset, as the procedure must start with the zero state.
We confirm with "Yes" to continue.
The measurement begins.
After the countdown of 20 seconds has expired, we have obtained the following measurement:
The height of the measurement curve can now be shifted using the left vertical slider so that it is as close as possible to the gray reference curve.
Note that TuneEQ will try to reach the reference curve. This should not be done by pushing many EQ bands too hard, but rather by lowering them.
Once the left vertical slider has been set correctly, it should not be moved during the entire measurement process. The volume of the radio (or other source) should also not be changed during this time.
The right-hand vertical slider can be used to move the height of the reference curve. This can be used later, for example, to measure a quieter rear system or a center speaker.
The left horizontal slider, for shifting the reference curve in the high-pass, was also moved down by 30 Hz, as the loudspeaker obviously plays 30 Hz lower with an electrical 220 Hz 24 dB Butterworth cut-off.
We want TuneEQ to use 27 bands (band 2 to band 29) and adjust the frequency response from 100 Hz to 20000 Hz to the reference curve.
Now that all the parameters for TuneEQ have been set, we can select the "TuneEQ Calculation" box.
The green curve now shows which equalizers TuneEQ wants to use:
Now click on the "SetEQ" box:
This applies the calculated parametric bands in the EQ:
A control measurement can now be carried out by selecting "Start Measurement" again.
In the window that pops up, simply select "Just Measure":
After 20 seconds of renewed measurement, the following measurement result is obtained, which is very close to the specified reference curve:
This curve can now be saved under one of the memory buttons before continuing with further measurements.