Room anomaly from corner placement. The other side makes up for it with a slight boost.
(that's the stuff where a Sub could help me out so I don't have to use the other channel)
At 30 Hz you see more heavy lifting being done by the left channel. The right channel needs way more boost because it doesn't have that corner support. This way one channel makes up for the other's imbalance, so both use similar amount of boost as to not run out of digital headroom.
Here's the 6 cycle plot including the Left + Right sum
(that's the stuff where a Sub could help me out so I don't have to use the other channel)
At 30 Hz you see more heavy lifting being done by the left channel. The right channel needs way more boost because it doesn't have that corner support. This way one channel makes up for the other's imbalance, so both use similar amount of boost as to not run out of digital headroom.
Here's the 6 cycle plot including the Left + Right sum
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I'd use A+B to see if the phase lines up, it should be about 6 dB higher. Better would be to record it out in the room and just run a sweep running both speakers. That's what I do.
The predictions are always just that bit smoother than real life measurements.
Near field looks awesome though, I'm jealous. An advertisement for using DSP on a set of full range drivers in the near field if I ever saw one.
The predictions are always just that bit smoother than real life measurements.
Near field looks awesome though, I'm jealous. An advertisement for using DSP on a set of full range drivers in the near field if I ever saw one.
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Thanks. I'm very happy with it and will probably stop messing around for a while. I think this is the right recipe for my room. Though I may step up to some big 4"
speakers soon
. By the way, I've been listening with a linear phase LR HP filter (-6dB at 32 hz) which is not showing in my measurements. Anyway, as you can probably gather from the SR/FR, and knowing that the reflections are about 22dB down (according to the IR in dB), it's a pretty accurate system. Mono recordings
sound small and centered/focused, while piano/choral/orchestral recordings have a soundstage size that is sometimes hard to believe. I think the symmetry and
diffraction properties of the speakers help with that also. Most importantly though, the timbre of instruments is correct.
That's not what the theory says. You know, the figure 8 pattern.
It will largely depend on where the speaker is placed. That energy coming from the back of the cone has to go somewhere. So it will probably bounce back at some time. If it creates strong peaky reflections it will cause comb filtering.
When I look at theoretical dipole behaviour I always get the feeling I'm looking at a comb filter pattern even without taking in account the reflections.
Diffraction will also come into play.
Here's a link showing some interesting examples. You see baffle shape does matter with dipoles, a true dipole would present 'comb filter like' pattern behaviour, the famous dipole peak being part of that.
Comb filtering is always associated with line arrays, I wonder why it's almost never mentioned in relation to dipoles. The baffle makes the difference, personally I don't think it's that good a compromise.
It will largely depend on where the speaker is placed. That energy coming from the back of the cone has to go somewhere. So it will probably bounce back at some time. If it creates strong peaky reflections it will cause comb filtering.
When I look at theoretical dipole behaviour I always get the feeling I'm looking at a comb filter pattern even without taking in account the reflections.
Diffraction will also come into play.
Here's a link showing some interesting examples. You see baffle shape does matter with dipoles, a true dipole would present 'comb filter like' pattern behaviour, the famous dipole peak being part of that.
Comb filtering is always associated with line arrays, I wonder why it's almost never mentioned in relation to dipoles. The baffle makes the difference, personally I don't think it's that good a compromise.
the problem is: how does one toe in a wall?
With a hammer, a saw, and a divorce lawer.
What do you run in wine to execute the scripts? Or is it as simple as "wine XXXX.bat"
Here's a quasi-anechoic measurement (sort of ...quasi-quasi-anechoic?) of my Pluvia Seven Hypercubes (avg. of both speakers) using REW. A 3" measurement was merged with a (gated) 18" measurement at 3kHz (about 2.5 oct above predicted baffle step f3). The total response was windowed (FDW) at 1/12 octave. No dac or mic calibration was used.* I used this to run some filters with REW and I think they work very well (in conjunction with predicted baffle step compensation). One filter does not use any boosting and would be more like what could be done with a (complex) electrical speaker network. The other filter uses boosting and cutting to totally linearize the response (at the expense of a little digital gain reduction).
*I posted the same measurement in the Pluvia Seven thread with dac compensation used (my dac rolls off a bit in the top octave)
*I posted the same measurement in the Pluvia Seven thread with dac compensation used (my dac rolls off a bit in the top octave)
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