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This is a quote from Roger’s email to me with explanation:
The curves in the diagram ‘Controlled Horizontal Dispersion Using Adjacent Flat-Cells’ is based on ideal circumstances. There are things in the acoustic environment such as equipment characteristics, room acoustics, etc., that affect the sound field. In order to keep the discussion simple the diagram does not recognize these. Concerning the controlled horizontal dispersion, a cell radiates sonic energy much like a flashlight radiates light. The beam is most intense at the center and energy tapers off as one deviates from the center. Using a meter one can measure a loss of 6dB along with the angular departure from the beam center line. A flashlight uses a very narrow spectrum of frequencies so it appears that the dispersion angle is always the same. However, with a speaker there are about 10 octaves of frequencies, and we have to confine our thinking as to what frequency we are looking at since In any radiator, light, sound, ocean waves, etc., the energy dispersion angle is a function of the width of the radiator compared to the wavelength being radiated. It works like this, if the wavelength is small compared to the radiator the beam will be narrow. This is why tweeters are made small so that they have usable dispersion. In contrast, the reason why woofers spread bass energy everywhere is because the wavelength of bass frequencies is huge compared to the diameter of a woofer.
To make the story short, when I talk about dispersion in our speakers I am using the worst-case scenario, which is that I use a high frequency (20khz) to determine speaker dispersion. A cell has approximately 12 degree dispersion (at the -6dB points) at 20,000 Hz. I set the angle between cells at 12 degrees (-6dB points), which means that below 20,000Hz there will be no gap in the total dispersion of the panel. With the narrow speaker models I increase the angle a bit so that the total speaker radiation covers 45 degrees, but this is small and doesn’t cause a discernible sound gap. The beams of sound that you see on the drawing are the sonic beams at 20,000Hz. At lower frequencies the adjacent beams expand and crossover each other such that there is not a sonic gap, or vertical picket-fence effect when walking in front of the speaker.
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Hello to all,
Those tall narrow speakers in the ‘red room’ (and other room) are actually mine and are a result of working step by step with Roger to agree to make the narrow models. I have been representing Sound Lab in Japan for the last 12 years – here we have much smaller spaces (not concerned about wife acceptance) The narrow versions do extremely well in small spaces and also in near field or as monitors. I also showed another pair of them in Dallas together with another 5cell model.
I am working on some different language to describe the models and I have another website which I will keep also in English to help support anyone in the world as best I can. This is the ‘prototype’ just for reference.Changes will continue to come, but as the conversation has started I thought I should share what I have done so far. -
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I’m not sure what the dispersion angle is of the 3-6 cell models. I’m waiting to hear back from Roger about that.
Take a close look at the first video in the other thread. As Roger is explaining how the membrane is attached, he appears to be using a 3C model, most likely a 745. Note that the center cell appears face on while the two adjacent cells look like they are angled at about 22.5 degrees to give the 45-degree curve.
I guess the 4-6 cell variants would have cell angles that vary to maintain the 45-degree total.
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Ah, got the impression that it was a new order.
Actually, I knew someone had ordered a custom version some time ago, just couldn’t remember who.
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John V,
Thanks for the picture. Expanding it and reading the fine print was more informative than the video. -
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Thanks for the updates. I already knew Dr. West was offering sizes other than what is listed on the website which he plans on updating. Now it is official. The video introduction made it seem like there was new technology.
I think the move to more slender speakers is a great idea. I can see how it would generate more interest.
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To expand on ernestov’s comments, I received the following email from Dr. West when I asked “What’s new at SoundLab?”:
“Concerning new things going on in our company, we discovered that some people would like a more narrow version of our speakers.
I am working on our website and a dealer news letter to announce this. As you know, our panels use a single membrane. The supporting
frame creates flat sectors about 5 inches wide which are the length of the speaker. Each sector is angled with respect to adjacent sectors by
about 15 degrees to provide controlled horizontal dispersion. We have given these sectors a name: cells. As you know we
basically have three models and each of these models is available in 5 different sizes. Take as an example our Majestic 745. The
7 suggests the approximate height and the 45 gives the horizontal dispersion. The number of cells is a standard 7. However, the same
speaker is also available from 3 to 6 cells, so if someone wants a more narrow Majestic 745, for instance having 5 cells instead of the standard 7, the
model name would be Majestic 745-5C. I am not putting the number of cells on our standard models, only the narrow versions which are options.
Having this option provides a speaker that has less effect on room decor and helps to pass WAF (Wife Acceptance Factor). As you would
expect the approach reduces bass dynamics some, but surprisingly not as much as I had expected. Anyway, this is the latest innovation and
is something that you can mention to others as it is now available.”In a subsequent email, Roger wrote:
” I am not offering them as
independent models. Rather, I am offering them as variations of our standard
models, which is in fact the case. We are demonstrating them in the South-West
Audio Fest in March to see how much interest develops. I have attached a
copy of a photo, see below, that we are using, which shows our most narrow model, which is about 20 inches wide. -
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I just spoke to Soundlab. I got all the info. No need for you guys to call them. The new design was a compromise meant to mitigate the wife-acceptance factor. It uses the exact same technology as the existing 745 but with less than half the surface area but it sacrifices efficiency. The new 745-3C is beautiful, slimmer and sexy but not at the same level as the existing 745.
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What a total gas bag. In 9 minutes I learned nothing about the new speaker. I wanted to know if there were design changes from my 545PX. Total waste of my time watching this video.
I got to the video through an email so I missed the tip to go to the 4-minute mark. Even so, there was no real information.
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