‘modern’, ‘mainstream’ speakers—too many models converging towards too similar a sound

@blueranger said: "There’s lots of tower speakers around. I wonder if they are trying to follow consumer trends by having a small footprint?"

I’m pretty sure that’s it.

I think it’s a symptom of a world in which listening to recorded music is a much lower priority than it used to be.

Imo that narrow footprint imposes constraints on what a speaker can do. There is an argument in favor of narrow speakers from an imaging standpoint, but ime a good wide speaker can image as well if not better.

Twoleftears notes that there is also a particular "sound profile" that these narrow-footprint towers are converging towards. That may be because the way they all interact with the room is inherently fairly similar, and room interaction plays a major role in what we hear. Imo the narrow tower format is not a particularly good one from a room-interaction standpoint.

But "it integrates well into many domestic environments, and the styling usually ensures a decent measure of SAF". In other words, it sells well.

Imo, ime, ymmv, etc.

Duke

maker of fat speakers

Kosst_amojan wrote: "I’ve never heard or read where anybody of authority suggested wide baffle speakers image as well or better than narrow to no baffle speakers. The unavoidably suffer from artifacts relating to edge diffusion and the more pronounced way in which the surface projects sound. It’s just the physics of the thing."

Roberjerman’s example of the Snell Type A is an excellent one. Imo Peter Snell’s approach made far more acoustic sense than any of these narrow-baffle tower speakers.

Here is why a wide baffle speaker can image as well or better than a narrow or "no baffle" speaker:

First, it’s not sound "projecting" off of a wide baffle that degrades imaging; it is the time delay between the direct sound and the arrival of the edge diffraction. Edge diffraction adds false early timing cues that can degrade the image. In general the longer the time delay (up to a point) before those false timing cues arrive, or in other words the wider the baffle, the worse the imaging degradation. BUT if we could significantly reduce edge diffraction, that would reduce these false timing cues to the point of being inconsequential, and imaging would correspondingly benefit. This can be done, but it requires either a very large-radius round-over (the technique Peter Snell used on the Type A), or aggressive absorption, or some other technique or combination of techniques.

None of these diffraction elimination techniques can be accomplished on a narrow baffle because the round-over or absorption or whatever has to be a sufficiently large fraction of a wavelength in order to be effective. Therefore if we are serious about eliminating diffraction, the cabinet width is going to be fairly substantial.

In practice the lowest diffraction enclosure would be precisely flush-mounted into the wall, which is the technique high-end recording studios use, resulting in a baffle the width of the room, along with superb imaging. There will still be a reflection when the sound reaches the sidewalls, but by then enough time has passed that the imaging will not be degraded significantly (I can go into more detail about the timing of reflections and/or diffraction if anyone is interested).

Duke

Teo wrote:

"And....digital room and digital speaker correction does not fix this.
"Does not fix this.
"Does not fix this."

Agreed!!

Nor can DEQ fix radiation pattern anomalies.  How many audio shows have you done where you spend three expensive days with the speakers fighting the room, and that battle overshadows pretty much everything else you had hoped to showcase? 

Imo acoustic problems can only be fixed in the acoustic domain, because otherwise they will inevitably be super-imposed atop any signal, whether that signal is EQ’d or not.

I think mainstream speaker design today is largely driven by marketing research, wherein the question "what do the people want in a speaker?" leads to acoustically-compromised narrow-footprint towers. Imo this is in part because "the people" usually don’t know any better, but SOME people (those blessed with two left ears come to mind) learn as they listen and put two-and-two together.

That’s actually okay with me - I’d much rather all those big companies with their big R&D departments and big budgets keep trying to make a flawed idea work well, and leave wide-body speakers to us little guys and the people out there who listen with their ears instead of their eyes.

Duke

Kosst_amojan wrote: "There’s all kinds of ways of managing edge diffraction! On narrow speakers the time delay is virtually insignificant and it’s really only a problem in the treble region... It’s just technically convenient to drive the diffraction problem up the spectrum because higher frequencies are easier to manage. "

I think you have a misconception. It sounds like you think diffraction can be limited to high frequencies by using a narrow baffle. This is not the case. What a narrow baffle does is, it reduces the time delay between the arrival of the non-diffracted direct sound and the arrival of the diffracted sound.

(One thing a narrow baffle does do is, it raises the "baffle step" frequency, which is the frequency at which the baffle’s face no longer acts like a 180-degree horn. Perhaps this is what you were thinking of?)

I think a brief explanation of how the time delay of a diffracted signal impacts imaging is called for. Apologies in advance for getting technical here; to anyone who dislikes technical discussion, please avoid the next paragraph:

The ear derives directional cues primarily from the first .68 milliseconds of a signal. This is the time it takes for sound to travel about nine inches, and correlates to the distance around the head from one ear to the other. Diffraction or reflections arriving within that first .68 milliseconds tend to degrade the imaging because the ear gets a false secondary early-arrival cue that normally would correlate with sound that had reached one ear first and then travelled around the head to the other ear, diffraction’s time delay mimicking the arrival at the second ear. A small time delay (narrow baffle) would correspond to a smaller false angle for this false cue, while a larger time delay (wide baffle) would correspond to a larger false angle. So with a narrow baffle, the false cues are not as drastic. This is why, all else being equal, a narrow baffle generally has better imaging than a wider baffle. If the baffle is wide enough that NO reflections occur within that first .68 milliseconds, then the imaging should be excellent (which is what happens with precisely flush-mounted studio main monitors).

Diffraction has other negative effects which are beyond the scope of this post.

Kosst also said: "There are simple solutions to that problem too. Lenses, damping, horns of some sort."

I don’t know what you mean by "lenses" in this context.

Damping material has virtually no ability to absorb a sound wave travelling parallel to its surface; the sound wave has to strike the damping material at an angle in order to be absorbed by it. And the damping material has to be thick enough relative to those frequencies to absorb them effectively. If we want effective absorption the sound must strike the damping material at an angle, and if we want absorption down low enough in frequency then the damping material must be fairly thick in both width and depth.  A thick felt donut can help in the highs, but isn't going to do much in the mids. 

Assuming the horn itself is not a source of diffraction (most are), in order for a horn to have good radiation pattern control down low enough to usefully minimize cabinet edge diffraction, it must be fairly large... and now we’re back to having a wide baffle again, especially once we factor in the fairly large-radius lips the horn will need to avoid diffraction at its mouth. This is actually the technique that I use, but the result is not a narrow baffle.

Of the techniques you mention, aggressive use of damping material (combined with a small enough midrange driver to get enough damping material between edge of driver and edge of enclosure) sounds to me like the most promising for effectively minimizing diffraction in a relatively narrow-baffle speaker. I do not recall ever seeing this approach on any narrow tower speaker, probably because it would run counter to the primary purpose for using the narrow tower format in the first place: Aesthetic appeal.

Duke