Looking for a single 15" cab plan for Beyma MI100

Hi,

Everything is in th topic title...
I'm looking for a plan for a beyma 15MI100 in order to be used as
a low mid (from 90Hz to 250Hz)...
I'm just interested in a simple cab plan.
Thanks.

http://www.usspeaker.com/beyma%2015mi100-1.htm

Good start might be the box which Beyma specify for their response figures for the 15MI100 in their tech sheet: http://profesional.beyma.com/ingles/pdf/15MI100.pdf

Bass Reflex cabinet, Vb=75 L, Fb=70Hz.

Easily calculated using WinISD etc.

Be very aware of the low Xmax for these of only 2mm

Mik

Aya wrote: from 90Hz to 250Hz...

The 15MI100 is more of a mid driver than lowbass, therefor cutting it as low as the suggested 250Hz will put a majority of the frequency range where it excells most (250-1k) to waste.

And with a 2mm linear excursion limit (eg. X-max), you won't be able to use the drivers full potential bellow 150Hz either (without signifficant distortion), so if you really need to cut at 250Hz, I suggest you look for a different driver, which is more suitable for that application.

Anyways, here's a few pages from an older Beyma Enclosure Design workbook, which includes a couple of plans utilising the 15MI100:

uploads/14089/Beyma_Enclosure_Designs_2003_p17-18.pdf

Cheers

Well, with 90-250Hz, you are essentially looking for a kick-bin, and I assure you that "some good plans" for a 15MI100 based kick-bin, simply do NOT exist .

And regarding "avoid a Two way system as your plans propose" - just build it without the hole for the top section, as it pretty much is all about the internal volume, port length/size(area), and some bracing.

If you're looking for a hornloaded design (for those 90-250Hz), then look at the HD-15 plans, but the driver will struggle, as it is not designed for such application.

Aya wrote: So do you think this driver will be ok for 90-250 Hz frequencies ? http://www.bcspeakers.com/product.php?id=49 In order to put it in a cab like this : http://www.toutlehautparleur.com/images/BC_Speakers/conception_diy_italie/Plans_DIY_PDF/B&C_SPEAKERS_SUB_15.pdf

Yes, even though it's a rather low sensitivity driver, and the cab with its 114L rather aimed at a bit lower bass (and therefor not ideal for your application), it would work well in that box for covering something like 70-400Hz.

Just needs to be high-passed properly (f.e. 70Hz/24dB) to avoid excursion issues above 250W input power, and I would also suggest the inside of the cab to be reasonably damped with absorbtion material (wool, etc.) to minimize reflections and resonances at higher frequencies (150Hz+).

That said, if the cab was to be used mainly as dedicated kick (70-250Hz), then I would rather suggest an 80L box tuned to 50Hz, to squeeze the best out of the driver for that particular frequency range, while keeping the group delay and excursion at acceptable levels. Suggested high-pass for the 80L box would be 50Hz (up to 700W of input power), as compared to the 70Hz for the 114L box.

And then there is also the option to try the B&C driver in a HD15 enclosure (hornloaded), which could provide 3-4dB more (compared to the reflex loaded bin), though it would probably not sound good (~honky~) above 160-180Hz.

To modify the Sub-15 plan to give 80L internal net volume tuned to ~50Hz:
Internal dimensions: 400x530x450mm (w/h/d) (down from 400x550x590)
Port dimensions: 190x80x300mm (w/h/d) (down from 190x100x400mm)

Edit: And if needed, high-pass @40Hz/24dB, and it can be used without any compromise (up to full power) as an allround bass solution (50-400Hz, -3dB@50Hz, up to 125dB continuous output).

Hope that settles it. Have fun