In this article, Mike Thornton shows how to use the free Room EQ Wizard software to create the EQ Filter settings based on the speaker/room measurements and then transfer those EQ settings to the Avid/DAD SPQ card.

Ever since DAD released the SPQ card for their AX32 and then with the version for the Avid MTRX and now with the smaller version built into the MTRX Studio, users need to be able to analyse their speakers and room, and somehow transfer the results onto the SPQ card using the DADman software.

If you want an overview of the process showing how this can be achieved using the free Room EQ Wizard software, a low-cost USB measurement mic, and most importantly, how to transfer the measurements to the SPQ card then check out our article How To Set Up The DAD/Avid SPQ Card UsIng The Free Room EQ Wizard.

If you want a detailed tutorial on how to download, install and set up the free Room EQ Wizard, which together with a UMIK-1 USB measurement mic from miniDSP then check out our article How To Set Up Room EQ Wizard To EQ Your Monitoring System.

For a detailed tutorial on how to use the free Room EQ Wizard software to analyse your speakers and room and then be able to EQ your monitoring chain. check out our article, How To Analyse Your Room And Speakers Using Room EQ Wizard.

Back to this article, in which we will show you how to use the free Room EQ Wizard software to create the EQ Filter settings based on the speaker/room measurements and then transfer those EQ settings to the Avid/DAD SPQ card.

How To Set The EQ Filters And Transfer Them To An Avid/DAD SPQ Card

In this free video tutorial, Mike Thornton shows you how to use the free Room EQ Wizard software to take an average response of your room and speaker and create the EQ Filter settings based on the speaker/room measurements and then transfer those EQ settings to the Avid/DAD SPQ card.

Settings The EQ Filters

Once you are done we can move onto the EQ Filter stage. Open one of your measurement files, for this video, we will look at Front Right. With the Average selected, click the EQ button from the Toolbar. Check that the title at the top refers to the Average.

First, click on the gearwheel icon to open the Track Options window. Click on the Smoothing dropdown menu to display the smoothing options available. The Room EQ Wizard manual recommends using the Variable smoothing for responses that are to be equalised, which is what we are doing. The other default settings here are fine so click the gearwheel to close this window.

Now let’s work our way down the options on the right-hand side. From the top, check that the Equaliser is set to Generic. This is the closest we can get to the filters used on the SPQ card, but as you can see there are a number of standard units listed if that is what you are using.

Close Equaliser and open Target Settings. Where it says Subwoofer, click on the dropdown menu and select Full Range Speaker as we should be using full-range speakers rather than bass managed where ever possible.

Bring the LF cut off up to close to where your speaker rolls off, in my case, I am going for around 30Hz.

Leave Add Room Curve unchecked unless you want to use a target curve. 

Next, we need to set the Target Level so that it is in the middle of the curve. You can do it by eye or you can use the Calculate target level from response option and let REW do the heavy lifting here.

Moving onto Filter Tasks, make sure the Match Range is 20Hz to 20kHz. Now we come to an area of contention, whether you should attempt to use EQ to fill in the troughs in a response curve. 

Some say not at all so they would set both Individual Max Boost and Overall Max Boost to 0. Let’s do that and see what happens when we match the response to the target and then show the filters. You can see that all the filters are cutting, there are no boosts. 

If we go the other way and set both to say 10dB, you can see that the predicted curve is pretty well flat, but there is around 8dB of boost around 125Hz and a 10dB boost around 250Hz, both of which will have a significant impact on the system headroom, so I have chosen to go with 5dB and 2dB as a sensible compromise as this seems to flatten out the small dips but leaves the bigger dip alone.

Having settled on the settings for Individual Max Boost and Overall Max Boost I have chosen to aim for a 1dB tolerance with the Flatness Target. I have checked the allow narrow filters below 200Hz because this allows REQW to create filters to counter room resonances and then I have also checked the new option to vary max Q above 200Hz so that there isn’t a sudden transition in the width of the filters when we get above 200Hz.

Because we enabled the Show Filters in the trace Options we can see graphically what the filters are doing and how many filters are being used across the top. To see what they are doing numerically then we can click on the EQ Filters button to see what they are doing numerically.

Note that if you have an MTRX Studio, like me, and find that REW uses more than 16 filters then you can disable the filters from 17 and above and then rerun the match the response to the target, this should limit the software to using no more than 16 filters.

You could read off the filter setting from this window but there is an option there to export the filter settings as text, and this is what I prefer to do as it makes it easier to set up the SPQ card filters in DADman. You can add some notes like I have used 5dB for the Individual Max Boost and 2dB for Overall Max Boost. Click OK and then name the text file with the speaker name and save it where you want it. This produces a text file that you can use to setup up the EQ filters in DADman.

Importing the settings into DADman

Clicking on each of the speaker buttons will display the eq settings for that speaker. Clicking on the Centre button you can see that I have already completed the centre speaker so let’s move onto the Front Right speaker and I will show you what you can do.

Open the Filter settings text file, you have just created in Room EQWizard and arrange the windows so you can see both the EQ section in DADman and the Text file.

I prefer to highlight each line so I don’t misread the table and enter the wrong numbers.

Click the Add EQ button and the default setting for EQ 1 will display. Click on the frequency numeric field, and type in the frequency, from the text file and hit Enter. 

Click on the Gain field and type in the Gain amount from the text file and hit Enter.

Now click on the Q field and type in the Q amount from the text file. Note that DADman will round up or down some of the data you enter and the maximum Q is 10.

Step And Repeat…

Once you have done the first filter, it’s a matter of working your way through all the other filter settings until the speaker is set up like this. 

When you have completed the first speaker, you will need to repeat the process until you have set up the EQ filters for every channel.

Job done!