Two passive radiators - different placement than normal

[scott68]

Two Passive Radiators – theory – Instead of placing two PR’s on the outside of the box where space is a premium for a small speaker, would they work if inside the box? For instance, in the picture, there are two possibilities: 1. have the PRs exit at the bottom or 2. Remove the top bar and have the PRs exit out both ends. Or don’t do it because it doesn’t work well.

What are the advantages and disadvantages of both? I would assume if out both ends, then there might be a null of bass sound at 90 degrees but not sure. Maybe not, as two normal PR’s at opposite exterior ends of an normal enclosure, seem like a norm.
Thanks

 

[afa]

Bose have used dual internal PRs in their Bose MusicMonitor 2.0 speakers, and Edifier Luna HD e25HD also uses the same internal dual PR arrangement

cheers

 

[scott68]

Thanks. I see that the bose has openings at both ends and the edifiers have about a 200 degree opening. I would assume that Bose would have done the research so the two openings seem the best. Any other ideas from anyone about mounting two PRs in a small enclosure?

 

[chris661]

Go for it, it'll be fine. Bose did a nice job with their MusicMonitors - I did a write-up here: Bose MusicMonitors | grimshaw-audio

I don't think there's a particular compromise (or lack of) from firing out the sides. There'll be a small additional air mass which will lower the PR tuning frequency a touch, like a Ripole subwoofer.

Chris

 

[oon_the_kid]

I think it would be fine, putting them in this manner also results in vibration cancellation. However you should not make the slot too small or the air movement will cause "chuffing" noises.

Oon

 

[scott68]

Thanks Chris and others,
Nice review: So I think I will try it.