Bipolar MLTL CSS FR125SR

[schmeet]

Hi all,

I was thinking of building this design by Jim Griffin.
Not so sure that i want bi-polar though. Would there be any effects of having both drivers facing forward (centered around the original driver placement).

Logic tells me the resulting FR should be identical but thought i better ask first..

Cheers,
Pete

http://homepage.mac.com/tlinespeaker...LDesignPak.pdf

[chrisb]

Originally Posted by schmeet

Hi all,

I was thinking of building this design by Jim Griffin.
Not so sure that i want bi-polar though. Would there be any effects of having both drivers facing forward (centered around the original driver placement).

Logic tells me the resulting FR should be identical but thought i better ask first..

Cheers,
Pete

http://homepage.mac.com/tlinespeaker...LDesignPak.pdf

well, I think the effects would be that you'd lose the advantages gained from the bipole configuration, and that the measurable FR would not be identical - although by how much you could reconcile those differences to would you actually hear in a real room could depend on a lot of factors, and HP filtering one (i.e. "1.5 way") at around the baffle step frequency as determined by the front panel width could probably help mitigate some of the problems associated with comb filtering


if it's floor space / WAF that is restricting your consideration of bipole, another interesting configuration might be to top fire one of the drivers as in the Planet10 "castle" microtower design in the document posted below - however with the open voice coil on the WR/FR125, dust etc could be a concern.

http://homepage.mac.com/tlinespeaker...aps-150909.pdf

[planet10]

Moving the drivers both to the front would mean that you need to add some BSC and you lose the imaging advantages of a single driver.

The one ithing i would do would be to rotate the box 90 degrees and mount the drivers on what are now the sides. This will reduce the bipole dip somewhat. Mounting the driver on the side at the same level would also work. Top mounting would not be recommended as it would screw up the designed in driver offset.

The sum of my experience with the FR125 is to recommend 4.5 -7 litre aperiodic box with these for best performance.

dave