speaker parameters - enclosure size

[thombeal]

I have 6.5" vibe component speakers and would like to have proper enclosures for the woofers as they're mounted in the rear. I have various parameters but they don't mean a lot to me so hoping someone would be able to help me find the ideal enclosure size. I've tried finding things online to calculate it but i don't know how accurate they'd be and i don't really know what i'm looking at.

Revc = 3.4 Ohm
Fo = 77.441 Hz
Sd = 13.070 M
Md = 10.700 g
BL = 4.707 T
Qms = 11.048 8
Qes = 0.797
Qts = 0.744
No = 0.541 %
SPLo = 89.3 dB
Vas = 9.596 m
Cms = 395.614 u M/N
Krm = 1.62864 Ohm
Erm = 0.983
Mms = 10.667 g
Mmd = 0.817 Kg
Kxm = 4.607 m H
Exm = 0.7

 

[volxstu]

I have a very limited knowledge of TS parameters you are geting into a whole mine field there.
Besides i dont think that the TS parameters of such a speaker will help you much to design a sealed enclosure, as they are designed for slightly restricted infinite baffle.
I think that using your loaf is going to take precedence here buddy. How and where will you be building the enclosures and what do you want them to play. We know that the average door is around 0.5cu ft (do a little google research to confirm) so you are looking for around 1cuft and i would say before displacement for both woofers.
If it were me i would be thinking that we know that the speaker is designed to work in an enclosure that is effectively vented so my box would look a bit like below.
The magenta vents in the box acting a bit like a port and i am sure we can talk about tuning if you want to go with this sort of design.
Sorry if the pic makes no sense im on lunch lol need to be quick.

 

[paulbfd]

Stu's right, I wouldn't bother.

Chances are the t/s will spec a box of at least 20 litres.

 

[volxstu]

Did you take a peak at my design could possibly tune it to around 70hz .

 

[paulbfd]

Mate I'm clueless at all this box design malarky!

 

[punto_matt]

Sorry im being simple here but does he want to put front comps in a sealed enclosure?

 

[Ruuko]

yes very odd but not unheard of, I wouldnt bother myself.

 

[paulbfd]

No Matt...

mounted in the rear

 

[punto_matt]

i get it now

 

[thombeal]

i have comps in the doors and comps on mdf shelf for rear fill but i have subs in the boot so would like an enclosure to protect them and separate them from the sub.

if the enclosure is vented will that not defeat the point?

 

[volxstu]

No if you look at my design the box is vented from the top and the subs move air underneath.
I think if i am correct that i can get the side opening to be tuned at around 80hz (Ideal and very similar to a door) then you will see another chamber which opens upwards which we can tune a bit lower or higher depending on how it sounds and your tastes.

 

[thombeal]

ok that makes sense - i think! would the opening of the vent mean creating a hole on the parcel shelf too or would it still be within the boot space?

 

[volxstu]

You will need a hole in the parcel shelf. You are basically making a new MDF parcel shelf with a hanging enclosure

 

[thombeal]

ok so you think an enclosure of around 0.5cuft per speaker vented on the top. What size vent do you think?

 

[volxstu]

Yes around 0.5cu ft per speaker.
Hmm as to the vent i have never heard of it being done in this way so it is up to you as to how much effort you are prepared to go into. I think we are touching on new ground here. So you could either just cut a small slot in the top of the parcel shelf.
Or i will do my best to help you actually try and tune it which will be a fair bit more complicated.

 

[paulbfd]

Thinking about this a bit more....

Putting them in a sealed enclosure that's too small will do one thing - raise the lowest frequency the speaker will play.

Is this a bad thing considering? They don't need to be dropping low as the sub will do that.

 

[thombeal]

ok, thanks for your help so far! i think i'll have to make a start and see how it goes from there. the enclosure volume is the first place to start so i guess i'll try out 0.5cu ft as suggested and see where it goes from there!

how important is box shape? would there be a significant difference between a shallow but long box compared to a deep narrow box even if the overall volume is exactly the same?

 

[volxstu]

ok, thanks for your help so far! i think i'll have to make a start and see how it goes from there. the enclosure volume is the first place to start so i guess i'll try out 0.5cu ft as suggested and see where it goes from there!

how important is box shape? would there be a significant difference between a shallow but long box compared to a deep narrow box even if the overall volume is exactly the same?

Na shape shouldnt matter.

 

[volxstu]

Thinking about this a bit more....

Putting them in a sealed enclosure that's too small will do one thing - raise the lowest frequency the speaker will play.

Is this a bad thing considering? They don't need to be dropping low as the sub will do that.

Yes but surely there is raising the frequency and then strangling the sub to only play frequencies that will not be heard from the front.
The stage being at the rear would mean that if you tune to around 70-80hz you will be adding to the punch of the sub rounding off the sound very nicely.

 

[thombeal]

The stage being at the rear would mean that if you tune to around 70-80hz you will be adding to the punch of the sub rounding off the sound very nicely.

By stage do you mean where a majority of the sound is coming from? the rear speakers are really for rear fill more than anything. i have amped comps in the front which is where the sound really is.