onken for eminence alpha 8 in a floor stander type enclosure?

[donovas]

i was hoping to build a tall floor stander type enclosure with alpha 8 and de10 horn. something with a troel's tqwt dimensions but with onken ports. apparently the onken calculator is telling me that it's a lousy idea.

mh-audio.nl - Home

am i correct in understanding that the port length must follow the same ratio as the port width? so that to increase one the other must also increase?

so it would be impossible to have an onken enlcosure 100cm tall without breaking the 35cm port length guideline? ....

 

[sreten]

Hi,

Port length is directly related to one dimension of a rectangular port.
Reduce the width by a % to reduce length by the the same %.

Note :
Don't trust pointlessly dogmatic online calculators.
They are nearly always pointlessly wrong.

rgds, sreten.

 

[planet10]

Now my miniOnkens are not officially Onkens (they just look like them), but they have proven to work well. I gift you this, if you want drawings email me.

40 litre 55 Hz tuning, slots 9 to 12mm wide should work. For instance 2 vents 12mm wide by (total) 70mm height by 312mm deep.

30 litre 55 Hz tuning, slots 9 to 12mm wide should work. For instance 2 vents 10mm wide by (total) 60mm height by 309mm deep.

I like the shape of the curve of the 2nd one better, they both have the same F10 which is 40 Hz. The 2nd has a gentler roll to get there. The extra volume of the 1st one might be needed to reach the floor.

dave

 

[donovas]

thank you so much for restoring hope in me, both gentlemen.

dave, i will send you an email.

thank you once more. the project is greenlit!

 

[donovas]

ugh.. beta 8. sorry, wishful thinking. xD

 

[planet10]

Beta 8 doesn't go as low as the alpha.60+ F10.

dave

 

[donovas]

Could i please get more insight on designing this enclosure? The calculator keeps giving me weird numbers- if i keep it to the height that i want (100cm ish) either the port is freakishly long or the volume is too unrealistic.

Maybe i should take a different approach? Since it's no longer an authentic onken, calculate for slot loaded tl instead and spread out the port onken style?

 

[Eldam]

i was hoping to build a tall floor stander type enclosure with alpha 8 and de10 horn. something with a troel's tqwt dimensions but with onken ports. apparently the onken calculator is telling me that it's a lousy idea.

mh-audio.nl - Home

am i correct in understanding that the port length must follow the same ratio as the port width? so that to increase one the other must also increase?

so it would be impossible to have an onken enlcosure 100cm tall without breaking the 35cm port length guideline? ....

One advantage of Onken design is you can full up with felt some of the ports section to adapt to your room : it's totally changing the tonal balance and sound can goes from boomy to tight with try & errors work...