We still don't know the in-room response. I mean, it's possible to squeeze some 2-3 dB here and there (moving the vent tuning or applying an impedance correction for the woofer etc) but the elephant in the porcelain shop are still the room, speaker placement and the listening position, ohh and the woofer itself if we talk about bass.
Here's the in-room response. Looks pretty bad to me, but there's probably multiple reflections and room modes. Unfortunately, I don't have a lot of options for speaker placement (as explained in post #12). I could get them a bit further from the back wall, and I could try some toe-in (but that wouldn't affect lower frequencies). I could also move the couch forward 30~40cm.
I'll do a quasi-anechoic measurement some time later to check if the real-world response is close to the simulated one.
I'll do a quasi-anechoic measurement some time later to check if the real-world response is close to the simulated one.
That's a pretty good extension to almost 20 Hz, no significant dips below 100 Hz, just 3 large peaks, two of them are 10+ dB and high Q, you can't do about these much with passive filtering or different box tuning, this cries out for DSP correction which with you can have pretty flat response below 100 Hz here by shaving down the peaks. The biggest problem is the large null between 100-200 Hz, you can't EQ that out, the causing reflecting surface needs to have some absorbtion or just play with speaker placement.
What you don't like subjectively in the bass?
What you don't like subjectively in the bass?
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I've used that woofer and heard others use it this way and that. 1-1.5ft^3 is about the perfect range for it, which you are at the larger end of.
Yes, agreed the lowpass coil is making your peak there. Sometimes a higher DCR coil will also be beneficial here to reduce the peak, albeit at a little reduced sensitivity. Using a smaller value coil and moving up the lower xover point can help too. Since the woofer is 90dB with coils in parallel, net system sensitivity should be 84-86dB at best after BSC, and not bad to start with.
I personally think the port should be a 2.5" diameter minimum, and that they should not be so close to the wall. By placing them that close the midbass emphasis will become chesty. You asked about nearfield responses, and in a vented design, a nearfield of the woofer will show a dip at port resonance. At farfield, this does not happen, and the decreasing output slope is eliminated. This is why nearfield is for bass tuning eliminating the room, and farfield is for everything above about 500Hz.
Yes, agreed the lowpass coil is making your peak there. Sometimes a higher DCR coil will also be beneficial here to reduce the peak, albeit at a little reduced sensitivity. Using a smaller value coil and moving up the lower xover point can help too. Since the woofer is 90dB with coils in parallel, net system sensitivity should be 84-86dB at best after BSC, and not bad to start with.
I personally think the port should be a 2.5" diameter minimum, and that they should not be so close to the wall. By placing them that close the midbass emphasis will become chesty. You asked about nearfield responses, and in a vented design, a nearfield of the woofer will show a dip at port resonance. At farfield, this does not happen, and the decreasing output slope is eliminated. This is why nearfield is for bass tuning eliminating the room, and farfield is for everything above about 500Hz.
I think I might be corrupted by the speakers I used before these. It was basically a couple of Voxel mini subwoofers with mids and tweeters added. The low end was driven separately and DSP'd. For these new speakers I didn't want to use the DSP (MiniDSP 2x4), to keep the signal path cleaner.
Looks like a pretty normal in-room response, with multiple room modes and a floor bounce dip. The room sim tab of REQ might give you some insight into where your room modes fall, and whether positioning can help mitigate them. You could try laying the speaker on its side and measuring with the mic on the floor (quasi-ground plane) to eliminate the floor bounce.
Here are a couple of links I find useful:
http://tripp.com.au/sbir.htm
https://amcoustics.com/tools/amroc
Bill
Here are a couple of links I find useful:
http://tripp.com.au/sbir.htm
https://amcoustics.com/tools/amroc
Bill
So the classic "which finger should we bite". You need an acoustically very good room and speaker/listening postition placement if you want deep and clean bass without DSP. There are other, more 'audiophile" miniDSP products like the new Flex or the SHD whose can act as a preamp, they are really good, the regular 2x4 is the very low-end of them.