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I would disagree on that. A few years ago I was at an Axpona show in Atlanta and they had saxophone groups play in one of the large conference rooms. Obviously poor acoustics but the sound was amazing, especially when the largest ensemble perform (20+ players I believe). Some sounds were spacious / wide with others very specific depending on how the horn projected. In my experience very directional speakers fall short when reproducing this kind of music. The room has to be energized to a degree in order to give you a sense of space and envelopment. With speakers that have a more narrow horizontal coverage I find the sound to be what I call "formatted" in that it's just not as realistic or engaging. Vertical coverage affects this as well but not as much as the horizontal plane.
A good friend of mine told me that audiophiles tend to "hear with their eyes". I'm wondering how the other formats (dipole, waveguides, etc) would fare under a blind test. Last year I attended an event where most of the listening was blind except for a few guys and myself who were switching out the speakers. It was interesting to see the owners try to guess if it was their speakers.
Honestly Rick you can have your cake and eat it too. What I ended up doing was adding diffusion to my rear side walls and rear wall. That completely provided the 'envelopment and spaciousness' while the narrow controlled directivity design provided my 'image lock.' The reverb contributes to spaciousness and envelopment. Treating the 1st reflections with absorption with narrow controlled directivity speakers made an improvement in the space between instruments (i.e. blackness), although, the improvement was small (This is most likely due to the design of the loudspeaker itself). For my front wall ,behind the loudspeaker, I have diffusers as well, which I interchange with absorbers. The diffusers are used for 2 channel and the absorbers are used for HT. To each their own I guess. But after having listened to numerous designs that are wider dispersion and some degree of directivity control, I only became convinced and satisfied when I started listening to speakers with narrowing and constant directivity. So my choices became limited, basically well designed waveguide based loudspeakers, or well designed OB speakers like Linkwitz latest LX series.Best,Anand.
A good friend of mine told me that audiophiles tend to "hear with their eyes".
I think there is a lot of truth to that statement. I am still in my 30's (at least for a couple months) but I feel like I am getting old and jaded with this hobby. Certainly I've become much more of an objectivist, or at the very least put things into what I think are the priorities (acoustics/speakers >>> cables and tweaks) and spend effort and money accordingly. I mean the hobby seems to focus and pride itself on being able to hear the subtlest minutia, presumably with the hopes that numerous small changes add up to some grand nirvana of sound. But I think many/most of these differences counteract the others, except for the ones we can objectively measure and analyse so we can shape the system as a whole. I'd trust my ears if something measures better but sounds really off (can't say that has ever really happened in my experience) but I'd want to know what was going on, so I wouldn't just give up on the measurements. I also recognize that biases are hugely impactful on our perception. To deny such or to think you are impervious to biases is foolhardy. This is where at least some controlled blind testing of sorts helps a lot. At least you know where you are susceptible.
It has been demonstrated that it is impossible to obtain: (A) perfect acoustic summing (flat frequency response), (B) perfect phase match AND (C) flat Group Delay using a simple analogue passive crossover [Vanderkooy, J. and Lipshitz, S. P., “Is Phase Linearization of Loudspeaker Crossover Networks Possible by Time Offset and Equalization?”, J. Audio Eng. Soc., vol. 32 (Dec. 1984)].(5)Given (3) and (4) above, a number of efforts have been made to design "quasi-optimal" crossovers that strike the best possible balance between the three goals (A),(B) and (C) (rather than only considering (A) - e.g. conventional 3rd order Butterworth, or (A)+(B) - e.g. even-order Linkwitz-Riley).
Nice link! They have a bit of added complexity due to focusing mainly on horns.For a non horn speaker, something like the miniDSP is nice because you can simply dial up different crossover points and slopes and actually measure the results from a phase standpoint, and do it iteratively to see if the theory matches practice. Also you can deal with group delay separately from phase because the miniDSP has a separate digital delay function tied to each individual driver. What I've noticed is that phase is reasonably easy to deal with when using a lower order filter, but goes all to hell when using higher order filters. Now, a steep filter is nice because it allows you to have a clean frequency response transition so it's ideal for people that feel phase is not audible. For myself, I like the idea of steep filters, but they always sound lifeless and sterile when I actually use them.
SL has picked up Dr. Toole's recent talk and provides his input: http://www.linkwitzlab.com/links.htm#TooleBest,Anand.
I somehow always forget to go back to Linkwitz's page for updates. There are some really good links on that page!
I am not an expert on the matter, but to my understanding the problem with steeper filters and phase has to do with the rolloff of the actual driver with the filter in place doesn't match the textbook roll off, usually because drivers don't have perfect response. Their impedance plots aren't perfectly smooth. They have breakups, notches, etc that need to be accounted for in the steeper filter to match the textbook. Then and only then is the phase more idealized. This is why off the shelf xo filters don't work well.
I think Duke here on AC at Audiokinesis has done some very interesting work regarding CD/swarm based speaker systems, very much in the Geddes mold. But even MORE interesting has been his development of the LCS (Late Ceiling Splash) technology - basically it's a CD speaker firing forward, and a 2nd CD speaker firing upward. This gives the laser like focus of a traditional CD speaker, but also gives the air and soundstage width/depth/spaciousness of an OB speaker. It's really a remarkable design.
