S10 OB - Seas L21RNXP on Open Baffle
After completing my last iteration, I really don't feel the need to experiment with different speakers / OB topology. Any improvements I thought, would come from the drivers themselves which unfortunately is about $$$, not engineering. I should also start to make a PCB and perhaps paint the speakers or something like that :)
But when I saw someone is selling a pair of Seas L21RNXP really cheap on ebay I couldn't resist having a go at rigid piston driver. The Seas drivers are beautiful indeed, and this is not even the magnesium series. They were old types of drivers but never used. The newer ones are L22RNXP.
What I would like to gain from this one are:
- Ability of the midrange to cross lower than P13WH. Let's say 120Hz, presumably better integration with the woofers.
- Transparency of rigid cone drivers. Is the claims true?
- Much higher SPL level
And some drawbacks I would expect/investigate:
- The need to cross the mid to tweeter lower, possibly straining the tweeter.
- Would the increase of baffle from 19cm to 24cm affect the polar response in a really bad way?
- Metal cone resonance
Build process is discussed at diyAudio. See interesting finding here. Measurement data available and discussed here.