Recalculate MLTL for Supravox 285 or 215 woofer

When I posted the 90 X 32 X 57.pdf I only filled out the Part 1 spreadsheet parameters to match the original MLTL parameters. That's why you see such a large difference in output level. Here's the updated system response and the complete .pdf with Part 1 and Part 2 parameters completed. To verify I didn't make any mistakes you should compare all the parameter values from both .pdfs (original and 90 X 32 X 57 Parts 1 and 2).

View attachment 1320405
Thank You very much Enrperkins and Grindstone! 🙏
I compared the two simulations, some random considerations:
  • Port radius has been increased from 6cm to 8cm. I guess is a choice to improve the bass response. Isn't it?
  • Cabinet size in the Part2 seems to be still the original one, I don't know if it makes any difference in this part of the calculation (attached picture)
  • Results show that with the re-sized cabinet we lose about 5Hz of bass extension. If this is bad or not... I don't know, especially considering that I will add subwoofer later. The resized cabinet is also flatter between 70-200Hz, but the bump at 47Hz is several dB louder than the original one. Is this more a "BR behaviour"? Will it sound more "boomy"?
I really would like to have your opinions about the comparison of the two boxes! :)

P.S, One thing that is not very clear from me is where is the transition between MLTL and BR in the theory. 🤔


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