Can I do more for my 2.1 system?

[sm52]

Try excluding miniDSP from the playback chain. Connect your computer to an external sound card or external DAC, then to a power amplifier, then to the left main speaker. Check what the impulse looks like in this case.

 

[Calypso]

Try excluding miniDSP from the playback chain. Connect your computer to an external sound card or external DAC, then to a power amplifier, then to the left main speaker. Check what the impulse looks like in this case.

Installed REW on my Mac and tried it from there, no change. As you suggested, I will removed the MiniDSP from the chain but leaving shortly on international business trip, so will tackle this again upon my return. Thanks for the support.

 

[Calypso]

@sm52 - SInce the mic was close to the wall, I added pillows, remeasured, inserted the delays, remeasured and the L/R impulse graphs are attached. Assuming this is a good starting point, what would you recommend as the next step?

 

[sm52]

This means the equipment is normal. Glad to hear that. Take three measurements, with the left channel as reference, for three speakers. For best results, make the full frequency range 0-24 kHz. Including for the sub. With delays and filters disabled. Place the microphone at the same distance from the main speakers at your listening position.

 

[Calypso]

This means the equipment is normal. Glad to hear that. Take three measurements, with the left channel as reference, for three speakers. For best results, make the full frequency range 0-24 kHz. Including for the sub. With delays and filters disabled.

Completed - L (3), R (3), SUB (3), No Crossovers, No PEQs, No Delays, use L as acoustic reference, 0-24 kHz. What is after this?

 

[sm52]

What is after this?

Next, you need to align the impulses of the main speakers. If you measure them from the center point between them, they will already be aligned. In previous measurements, the main speaker graphs started at 35 hertz. Required from 0 hertz. To see at what frequency to cut the filter to match the sub. Pre-set the delay for the sub at its first big peak. Then turn on the filters at the frequency that seems best. 12 dB/oct. Make measurements of three speakers with these filters. Then, in the 'Alignment tool' on the 'All SPL' tab, see how the phases add up separately for the pair left + sub, right + sub. At this moment, adjust the subwoofer delay for one pair. Then for the second one. If the delays are approximately the same and the phase addition is good (there are no large amplitude subtractions), leave it that way. If something is not good, change the filter cutoff frequency, take measurements and repeat the previous steps to match the sub with each speaker. It is possible to change the filter cutoff slope to 24 dB/oct. And so on. Usually there is a big difference in the delays for the sub for one side and for the other. Therefore, the process may be long. So you will have to look for compromises in order to stop.

 

[Calypso]

Next, you need to align the impulses of the main speakers. If you measure them from the center point between them, they will already be aligned. In previous measurements, the main speaker graphs started at 35 hertz. Required from 0 hertz. To see at what frequency to cut the filter to match the sub. Pre-set the delay for the sub at its first big peak. Then turn on the filters at the frequency that seems best. 12 dB/oct. Make measurements of three speakers with these filters. Then, in the 'Alignment tool' on the 'All SPL' tab, see how the phases add up separately for the pair left + sub, right + sub. At this moment, adjust the subwoofer delay for one pair. Then for the second one. If the delays are approximately the same and the phase addition is good (there are no large amplitude subtractions), leave it that way. If something is not good, change the filter cutoff frequency, take measurements and repeat the previous steps to match the sub with each speaker. It is possible to change the filter cutoff slope to 24 dB/oct. And so on. Usually there is a big difference in the delays for the sub for one side and for the other. Therefore, the process may be long. So you will have to look for compromises in order to stop.

Steps to Align:

Select Overlays/Impulse, select all mains
Select remove IR delays for all measurements

Is this correct?

 

[sm52]

I will not evaluate other people's recommendations. I expected you to take a few measurements without adjustments, then with some adjustments, I'll see how best to match the three speakers. If the result suits you, the job will be done.

 

[Calypso]

I will not evaluate other people's recommendations. I expected you to take a few measurements without adjustments, then with some adjustments, I'll see how best to match the three speakers. If the result suits you, the job will be done.

I like the plan. Just wanted to make sure I understood how to action the next step. I did the step I described (impulse alignment) above and then went to the SPL graphs, 1/12 smoothing. The highest, first peak is the left speaker at 50Hz, so I will enter this into MiniDSP speaker/sub HP filters with 12dB/Octave and remeasure. Makes sense.

 

[sm52]

SPL graphs, 1/12 smoothing. The highest, first peak is the left speaker at 50Hz

Pre-set the delay for the sub at its first big peak.

I wrote about using the first big peak of a sub on the impulse graph to set the delay for the sub. More precisely, negative delay. Because in fact, the sub always needs to be done earlier. Or delay the main speakers.

Looking at the last picture, you should try to make the cutoff frequency for the main speakers 140 hertz, and for the subwoofer 110 hertz.

 

[Calypso]

Here is where I am after re-measuring with the filters. I had to delete some measurements as the file is getting large. This will be a great thread for beginners.

 

[sm52]

Not good. Although the main speakers can be left like that for now. Raise the subwoofer level by 5 dB and try making a filter cutoff for it at 90 Hz 24 dB/oct.

I tried to determine the correct delays for the speakers by taking the measurements from post 17, and considering that the second impulse is a reflection. In the picture on the left you can see the delays for the right speaker and subwoofer relative to measurements 1,3,6. There are three impulses in the center after alignment.

 

[Calypso]

Not good. Although the main speakers can be left like that for now. Raise the subwoofer level by 5 dB and try making a filter cutoff for it at 90 Hz 24 dB/oct.

I tried to determine the correct delays for the speakers by taking the measurements from post 17, and considering that the second impulse is a reflection. In the picture on the left you can see the delays for the right speaker and subwoofer relative to measurements 1,3,6. There are three impulses in the center after alignment.

Just to confirm, low pass filter for subwoofer to 90Hz with 24 dB/Oct slope. Will re-run measurements with L speaker as reference. I also made the changes in the analyses settings. In listening, I feel a speaker crossover of 110 Hz sounds much better than at 140Hz.