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[Scott Carneval]

In the words of Sergeant Preston of the Yukon (for those of you who are old enough to remember that), "It looks like this case is closed."  Scott C. visited our building Wednesday afternoon with a newly developed speaker that (literally) sounds like it will cover the odd-shaped room very uniformly, well, two of them will cover the room, he just had one with him.  We had a great discussion about different gear that we might want to use with those speakers.  Of course, we still have to raise some money to buy them, but I think that's just a matter of time.  If I'm allowed to talk about brand and model I can try to explain how it will work, but I don't want to appear to be advertising where that isn't supposed to happen.  And Scott could explain it better than I could.

Thanks to all of you for a lively discussion and great advice, I look forward to thinking of another question to ask.  It's even possible that I could contribute to an answer to somebody else's question, who knows.

DD

The speaker Don is referring to is the Martin CDD10. The room itself didn't have many issues except for a bit of an echo in the extreme corners. RT60 was actually pretty tame. Knowing that they only had $1000 - $1500 to spend, it seemed like a waste for them to spend money to measure the room when there was no budget to treat it.

It was truly a night and day difference when we compared the CDD to their current speaker, although that was to be expected given the blown tweeters. The most impressive part to me was that Don was able to get more gain out of the mic than ever before, and the pastor was standing directly in the pattern of the speaker, maybe 6' away from it. There were maybe 4-5 seats on the extreme edges of the audience that were noticeably out of the pattern, but the speaker was only 11' in the air and, if he chooses to go with the CDD, the installed position would be about 18-20' high.

Also, the CDD has somewhat of a trapezoidal coverage pattern. The horizontal coverage at the bottom of the vertical pattern is 110º, while the horizontal coverage at the top of the vertical pattern is only 75º. If your speaker is flown and aimed down at the audience, this means that the area closer to the speaker has 110º coverage and the area at the back of the room, or the 'top' of the pattern, has 75º coverage. What we intend to do is rotate the driver 180º so it's upside down. This will give the front of the room a 75º pattern while the rear of the room has a 110º pattern. As I explained to Don, this pattern really only affects the top few octaves. Martin doesn't provide polar plots on their website, and what I'm told by the USA rep is that because of the unique pattern of the speaker most people would get confused by the plots. I intend to measure the speaker outdoors to really find out where it drops off, and at what frequency. If I had to guess, I would say the speaker only had control down to about 2k. But what I can say is that the speaker exhibited well over 100º of HF coverage towards the front, and it definitely narrowed to the rear.

We'll model the room first if Don decides to move forward, but I think we have a winner here.

[Jonathan Johnson]

Also, the CDD has somewhat of a trapezoidal coverage pattern. The horizontal coverage at the bottom of the vertical pattern is 110º, while the horizontal coverage at the top of the vertical pattern is only 75º.

I can see this pattern being useful in a rectangular room when flown at a narrow end.

Since the near seats would be in the 110° part of the pattern and the far seats in the 75° part, the effective width of the pattern could be the same from near to far, if the speaker is flown at the proper height and angle.

Turning the horn upside down, as you mentioned, could certainly be beneficial in a semicircular seating area, as the near area would be quite narrow and the far area quite wide.

The trapezoidal pattern is an intriguing idea that I probably never would have thought of.

[Jerome Malsack]

I dont have the words or script but does anyone have the recommended test for intelligibility, because most of their needs at the church will be the spoken word and the message and less on the music.   

[g'bye, Dick Rees]

I dont have the words or script but does anyone have the recommended test for intelligibility, because most of their needs at the church will be the spoken word and the message and less on the music.

Well, you could use this as a fall-back:

http://www.nti-audio.com/en/functions/speech-intelligibility-stipa.aspx

[Irvin Pribadi]

One thing perhaps worth checking is the amplitude "shading" of such inverted pattern.
The CDD10 design may have intended to have the narrow 75 deg coverage hotter than the wide 110 deg end.
Inverting this would result with a very hot near field and significant drop of SPL further away.

[ProSoundWeb Community]