3x8" in a TL

[wingman]

Hi is it possibly to make a TL with 3x8" ?

I have found these Vifa M21WP-00-16 but they are 16 ohm, so i where thinking about useing 3 of them per a side. = 5,33 ohm in paraelle


data:

Vas: 56,76
Fs: 34,1
Qts: 0,43
Qes: 0,52
Bl: 11,69
Re: 11,04
Sd: 235
Mdd: 29,92




I thinking of a Xt 19/25 or a fountek Jp2.0 for tweater.

Sorry my poor english

[Tomac]

is there any speciaj reason why they shouldn't be 8 ohm?Just use 2 of them.
I don't see any sense in using 3 drivers..2 will be just fine
I'll try to run the sim with two drivers.Judging by numbers it should work.If it was for me I would put them in ML-TL to shorten the pipe.
I cannot find any frq. response for this driver,it isn't listed on Vifa site.
Do you have any?
There might be a problem with tweeter ,you'll have to find one which can be cut low and that is if that bass is reasonably flat up to 2kHz.
I guess others should know about tweeter which can handle that.
Monacor has tweeter DT-300,you can cut it low.Haven't heard it though...

[Tomac]

100 cm long pipe
So=3 Sd
Sl=3 Sd

driver position=0.1
vent
L=1"
r=1.5"

densitiy=0.25 to 0.5



F3 is round 30 Hz.That should be enough I hope



It woučld be good to put the other driver on rear side to cancel up the baffle step
cheers

[wingman]

Originally posted by Tomac
is there any speciaj reason why they shouldn't be 8 ohm?Just use 2 of them.
I don't see any sense in using 3 drivers..2 will be just fine
I'll try to run the sim with two drivers.Judging by numbers it should work.If it was for me I would put them in ML-TL to shorten the pipe.
I cannot find any frq. response for this driver,it isn't listed on Vifa site.
Do you have any?
There might be a problem with tweeter ,you'll have to find one which can be cut low and that is if that bass is reasonably flat up to 2kHz.
I guess others should know about tweeter which can handle that.
Monacor has tweeter DT-300,you can cut it low.Haven't heard it though...

Vifa XT 25 is ok at 2K and so are fountek jp2.0.
I´ll look into Monacor DT-300 for sure !

Vifa M21WP is ok up to 2K i think, i´ll scan the frq. response to you.

[wingman]

Originally posted by Tomac
100 cm long pipe
So=3 Sd
Sl=3 Sd

driver position=0.1
vent
L=1"
r=1.5"

densitiy=0.25 to 0.5



F3 is round 30 Hz.That should be enough I hope



It wou
ld be good to put the other driver on rear side to cancel up the baffle step
cheers

will the pipe fit 2 driver ?

"driver position=0.1" is it 0.1 inch from top to speaker ( just to be sure)

Vent goes neer bottom

se attach file

[wingman]

better pic


the breakup around 1,3K is the dust cap, an is easy to fix.

just a littel damping


Thanks for helping me

[Tomac]

You'll definitely need Zoebel for crossover to work properly.This breakup at 4KHz is really nasty,you'll probably need 4th order crossover to fix it,maybe even notch filter,I'm not sure
It can be fixed for sure,you'll have to experiment a bit
box is modelled for 2 speakers.You choose where to put the other speaker,I suggest at back.
3 Sd is actually 6 Sd if you look at a Sd of a single speaker.I calculated total Sd so I wrote 3Sd.It will be pretty wide box.I'll run simulation again to see if we can narrow it down a bit
0.1 is distance from top of speaker,bu not in inches,but in aspect(I don't know if i'm explaining this right because I don't know all the apropriate english terms) it is like you divide box in 10/10 ,in your case this will be 10 cm (becuse 10 cm is tenth part of height of your box) you locate the speaker so its' center is on 90th cm of height.This means your speaker wiill be up to edge of the speaker box since it is 20 cm in diameter.(this way you understand for sure I hope)
port is on the bottom

cheers

[Timn8ter]

One suggestion, take it or leave it.
Set up the drivers in bipole fashion. Increases power handling, reduces cabinet vibrations and delivers smooth bass response.

[Tomac]

Hi Tim,nice to see you here!
1.It is tuned above 0.707 of Fs, actually 0.88 the way I calculated it
this makes no problem
2.I agree

[Timn8ter]

Yep, caught that and edited my response.