Horizontal Midrange Spacing in a 3-Way

[69stingray]

Hello Everyone,

What do people think of the following setup for the midranges in a 3-way? Assuming the baffle is wide enough, having two midranges side-by-side with the a small tweeter in the middle.

In the attached example, I am pictures two Hi VI B3N's with a little Dayton Neo. Tweeter. The Hi VI would be wired in parallel and crossed over to the Dayton Tweeter at approx. 4,000 Hz.

Any issues? I don't see this type of set-up very much and I know it is not liked in center channels due to lobbing, but with the speakers side-by-side and a crossover freq. practically at one wavelength....

[69stingray]

No comments?

[bjorno]

69 stingray:

I am pictures two Hi VI B3N's with a little Dayton Neo. Tweeter. The Hi VI would be wired in parallel and crossed over to the Dayton Tweeter at approx.4,000 Hz.Any issues? I don't see this type of set-up very much and I know it is not liked in center channels due to lobbing, but with the speakers side-by-side and a crossover freq. practically at one wavelength....

It would be ok to cross over at 4 kHz if the B3N's were vertically aligned but when placed horizontally you expect at least to cover the corresponding horizontal azimuth angle as the other drivers in your mains do and to avoid secondary lobing.

Then you must start crossing over at a lower frequency and if using 2nd order filters, I recommend crossing over at 2 kHz or at 2.5 kHz if a 24-dB/octave filter is used. The wide secondary lobe at 4 kHz will be 12 dB down.

The vertical c-c is very small and if extended by moving up the T-driver one inch matters very little. Design a conical 3.15” diameter and 1” deep wave-guide to make it possible to use a 2 kHz crossover.

b

1(2)

[mashaffer]

I am not informed enough to calculate any lobing issues but I just wonder what one would need two midrange drivers for. A single MR of reasonable size is enough to cause hearing damage it seems to me.

Did you have a particular goal in mind?

mike

[bjorno]

2(2)

[69stingray]

Preliminary goal is to raise the sensitivity of the B3N. They are only rated at 81 dB with 2.83 V into 8 ohms, that is 75 dB with baffle step lost.

bjorno - thanks for the simulations, I will have to study those.

[mashaffer]

Originally posted by 69stingray
Preliminary goal is to raise the sensitivity of the B3N. They are only rated at 81 dB with 2.83 V into 8 ohms, that is 75 dB with baffle step lost.

bjorno - thanks for the simulations, I will have to study those.

Gack! That is terrible sensitivity for a midrange. I guess that it is trying to be a woofer. It is I suppose a matter of taste but I would not pay that high a price in sensitivity no matter how smooth the frequency response. Even with two of them you are just getting into the barely acceptable range in my book.

In any case it seems that you are getting the needed input from some folks with real knowledge of placement issues. Best of luck on your project.

mike