Deqx pre8

The problem that I run into during the integration of a pair of stereo subwoofers using the Pre-8 is that all drivers’ relative sound levels, for both the main speakers and subs, are measured during the first step. Essentially, you place the measurement mic very close to each driver for left channels then repeat the process for the right. After all the driver measurements are collected for the left channels, graphic results are displayed of the response curve for each driver relative to each other. This in my case includes the left subwoofer sitting about five-feet behind the left main speaker and the same is on the right side as well. This seems to work well for drivers on, or nearly on the same plane, but for the subwoofer that I just took a near-field measurement, five feet (1.5m) behind my main speaker, is not going to have the same relative sound-level when measured at the plane of the main speaker.

In DEQX-Cal, used for legacy DEQX processors, you could match the level of your subwoofer to your main speakers by matching the subwoofer curve amplitude to the main speaker’s curve as measured from the sweet spot, but this was a manual process. You could also match impulse response of your subs to each other then both to the impulse response to your main speakers in order to set the correct delay. It appears now that subwoofer time alignment as well as time alignment of all drivers is performed automatically in step two with a provision to override (in distance).

But how could step two possibly set the subwoofer’s relative loudness when relative levels are set in step one and the subwoofer is substantially on different plane than the main speakers?

For me when I perform driver measurements in step one and close-mic my subs, the final outcome is low bass "lite".  As a kluge, which actually returned fairly good results, I made step-one measurements of the main speakers, in my case at 16" (40cm) then moved the mic along the same plane as I measured my main speakers to where the mic was directly in front of my sub and still on the same plane as my main speaker. This placed the measurement mic about 66" away from the front of the sub and I then took the measurement. I also limited the lower speaker correction (but not room correction) to 200Hz crossing over at 60Hz12dB/oct since the Apogee woofer panels go very low. The bass is pretty damn good now, but I know this couldn’t be best way.

Always open to suggestions.

Has anyone been able to connect to deqxy3.local through a VPN? I haven’t had any luck. So far I had to kill my VPN service in order for the connection to be made and use the Pre-8. I thinking that AWS (the cloud provider) must not allow a VPN connection but I don’t know for sure. Any thought on the matter?

Has anybody found a way to EQ individual drivers?  As opposed to EQing the summed frequency response. Thanks

I don’t think the software is there as of this latest release. You may want to submit this as a "Suggest a New Feature" request.

So far I’ve only submitted two request but I’m sure that I'll be adding more  soon.

The following are the two request’s that I have submitted:

1. For a provision to display the room response showing any automatic PEQ correction (if any) applied after all calibrations have completed. Also with the ability to auto-correct AND manually PEQ correct the room response.

2. For a provision in Volumio on the Pre-8 to allow installation plug-ins for the Volumio plug-in store.

As for the first request, if you have ever used the legacy DEQX-Cal, it has this feature. What was nice about it, is that it did have the Auto-Correct feature which by default would apply PEQ correction very conservatively. It gave you a great starting point and from there you tweak those setting or change it up completely. It applied the updates in real time where you could immediately hear any change. Right now as it stands, you cannot visualize room response at all. I assume that room response measurements are taken and adjusted automatically in step 3 of the calibration sequence.

The second request is asking for a feature at all other implementations of Volumio already have. Hopefully the Volumio folks can code this one for DEQX so that can keep working on enhancing the core product’s software.