The Dude Posted January 25, 2021 Share Posted January 25, 2021 Well that stinks, when looking at that dip around 80, it reminded me that my sub was still on here. Have I been chasing tail as I now have different readings with that bump again at 1.1k? Quote Link to comment Share on other sites More sharing options...
Chris A Posted January 25, 2021 Share Posted January 25, 2021 That highlighted area is the phase response wrapping because it's going outside of ±180 degrees. Just go to the "Controls" menu and select "unwrap phase", and that goes away. You will need to show an excess group delay plot in order to see what's going on in the blue-circled area. I don't see any phase reversals. Those would show discontinuities in the phase plot. I would also recommend zooming in on the vertical scale of the SPL plot--the control is next to the left side "Y" axis at the top when you bring the cursor into the field of the plot. I would increase the magnification to see 2 dB divisions on the plot. Then you will know just how far the SPL response is out. Right now, you're zoomed pretty far out. Chris Quote Link to comment Share on other sites More sharing options...
Chris A Posted January 25, 2021 Share Posted January 25, 2021 Exactly where is the microphone, top to bottom, relative to the top of the Bass bin? Try moving it up or down about 2 inches, then take another sweep and show the excess group delay plot. If the excess group delay spike at 1 kHz moves in frequency, then it is showing that you have more than 1/4 wavelength vertical separation between the HF horn/driver and the bass bin centerline, i.e., you can't do anything about that--the lobing is going to be there (only MEHs can avoid this, or very small loudspeakers without horns and having very small diameter drivers). Chris Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 25, 2021 Share Posted January 25, 2021 21 minutes ago, Chris A said: I would also recommend zooming in on the vertical scale of the SPL plot--the control is next to the left side "Y" axis at the top when you bring the cursor into the field of the plot. I would increase the magnification to see 2 dB divisions on the plot. Then you will know just how far the SPL response is out. Right now, you're zoomed pretty far out. That thing is tricky, I feel like if I attempt to get it that close, I screw everything up. Quote Link to comment Share on other sites More sharing options...
Chris A Posted January 25, 2021 Share Posted January 25, 2021 I think you were just right in terms of delay and polarity in the prior set of plots before this last one. You can now see that you have a little work to do with the SPL response. If you want a bit more help flattening the SPL response, you can export the FusionAmp configuration settings to a file (it's XML and very small), and also the .mdat measurement file from REW, and PM or email me (there is a limitation to PM size here that the .mdat file may exceed, but not my email (PM me for my email address). Chris 1 Quote Link to comment Share on other sites More sharing options...
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