Mid-Bass line array – Design & Driver Q’s

[JonFo]

Mid-Bass line array – Design & Driver Q’s

Hi Folks, I’m designing a line array to accompany a set of Martin Logan ESL panels (a set of Monoliths in this case).

I’ve already done a line array for my center channel project , using the awesome Adire extremis 6.8. That came out great.

But since the extremis are out of production, I’m looking at alternatives and would like your input as to what drivers are recommended to cover the range of 80 to 315Hz.
The <80Hz range is handled by an Infinite Baffle sub, so the drivers do not need to go low.

The resulting line array and constituent drivers must have very low distortion to best match the Electrostats.

I use speaker processors (DBX Driverack 260) as active x-over and EQ’s, so matching up the ESL to the line array is pretty straightforward (as far as these things go ).

My constraints are:

Line array to be roughly 4’ tall. (it will be mounted at same level as the panel, and adjacent).

That’s about it. Cost, while not unlimited, is secondary.

I’ve been looking at a lot of 8”, 10” and even 12” drivers for this, but have not really settled on anything. Therefore, please give me input on drivers and enclosures you think would apply well to these goals.

Thanks,

 

[JonFo]

Here are the drivers I’m currently considering for this:

8” Drivers

Dayton RS225 8” mid-bass. Seems to have good distortion characteristics in the frequency range I plan to cover. Cost is attractive $40/ea in the quantities I’ll order). Figure I can fit five of these in the 4’ array.
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-366


10” Drivers

Dayton RS270S woofer, seems to go clean enough into the 500hz range, and definitely covers the lower end (80hz) better than a RS225. But have not seen distortion characteristics for it. I’m really looking to keep third-order harmonic distortion in the 200 to 500 range well below -50dB and below the second harmonic.
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-366

HiVi D10G is a good woofer, and seems to be OK if crossed over before 500Hz, but again, wonder about distortion figures in the mid-bass. Also, good for my preferred alignment (sealed), but large 75 ltr. Sealed volume means 4 of these would be 300 ltrs. That a big box, even for one that could be 6’ tall x 12” wide.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=297-430



12” Drivers


HiVi M12, seems like a good match if wanting a big driver and high SPL for the combined Array.
Again, this would force a pretty wide 14” to 16” cabinet and of substantial size. Guessing 85 liters each for a sealed alignment would give extension to 60Hz.
I actually have a pair of these to try in the current 85 liter sealed cabinet of the ESL. So I’ll be able to measure them directly in a week or so and judge integration.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=297-456


That about it, look forward to comments and questions from the experts (and anyone else who cares to chime in).

Thanks,