Two full ranges on same baffle, what angle to prevent interference?

[18Hurts]

I really like the MA CHR70 Gen 3 (4" FR) and would like to use it with a Topping 15 watt T-Amp (the one with the USB DAC) To make the speakers 4 ohms, I'll use two drivers and they will be used in a box with two 5.25" passive radiators tuned for 45 to 50 Hz.

This should allow 100 dB output from a desktop which is plenty loud (I'll use a subwoofer if I want deep bass) My issues are using two full ranges in the same speaker--they will start interfering with each other so I want to make a 5 sided box--each speaker will be on it's own baffle and angled away from each other.

Is there a rule of thumb on the correct angle? 30 degrees would work nicely when I look at the 30 degree chart on the driver. Is that too shallow of an angle, just right or should I go 45 to 60 degrees?

Any help or insight is appreciated.

[sreten]

Hi,

It will be a lot easier to make a 0.5 way implementing BSC at the same time.
There is no optimal angle as they are not constant directivity drivers.

Vertical 0.5 way is the way to go IMO, avoids all two driver interference issues.

rgds, sreten.

[ßart West-VL.]

Originally Posted by 18Hurts

... I want to make a 5 sided box--each speaker will be on it's own baffle and angled away from each other. ...

Finally built a prototype, dual FRS8 in pentagon-TL

[18Hurts]

Thanks for the replies, guys!

I love the "0.5 BSC woofer" since my center channel speaker build is a 2.5 way running four 5" woofers--works well when the rules are followed. A great design that cures many problems--if you don't mind XO components in the path.

Bart, do you find any issues with blurring of the image when the speakers are angled at 72 degrees from each other? To simplify the design, I'd like to run 45 degrees for the front baffle then conventional 90 degree angles for the sides/back.

Full range is rather new to me and I like the MA stuff--just need to get the output up to 100 dB at 15 watts and 4 ohms.

[tuxedocivic]

How about one chr70 and a PR on the front, and the others on the back.

That chr70 has some built in BSC and nearfield on a desktop, isn't going to require full BSC.

[sreten]

Hi,

What people don't realize is you don't have to go full 0.5 way for a 0.5 way.
The idea is to let one driver have more output than the other, how you do
that is completely up to you, a 0.5 way does not necessarily do 6dB BSC.

rgds, sreten.

[ßart West-VL.]

18Hurts,

Since I still haven't completed the system, I can only say what my ears told me in mono-mode from one prototype.
While playing different kinds of music, I moved myself around the speaker, left to right to listen to any changes that may occur, keeping my ears at the same height of the speakers.
I didn't sense a lot of difference, HOWEVER, my ears only give me info to about 11500Hz!!
So this is totally subjective but for me, HT is about SURROUND and this system is very good at it, because the 72° is just right for the sound direction.

This pattern is valid up to 5700Hz, after that, frequency's don't ad up anymore.