A Thread for those interested in PPSL enclosures

[kees52]

Originally Posted by epa

its diffecult to get this driver to play low.
250 lts tuned at 20 hz .not verry small
if you punch the numbers from in the input screen,you cam play with the wizzard yourself.
click on the pic left bottom x to enlarge pic.

Thanks , I had also that same idea, a normal vented box was already 200 plus liters. but if I halve the vas then it get smaller, like a isobaric way and go low, but that is not a ppsl anymore.

high Sd and smaller VAS will work oke here.

thanks for your attemt I go play. the output on hornresp is good, 250 liters is big but if one box used, the rest is ob then it is oke, it has
good output I see.

How have I to involve the S1 S2 S3 in the box itself (misschien kan je dat even mailen via hier in nederlands, dank je alvast), and the slot? how do it act as we mass load the cones like in the ripole, I think that we then have to experiment with it, a slot who has the conus face each other, magnets in the box..



The peak at 200 plus hz can be easely cope with, to use a euhh zuigkring.

photo is the slot I did make for measuring.

[Juhazi]

My own project evolved towards PPSL too A bench style cabinet subwoofer 2x15 closed

It is in hiatus stage because I must wait for the drivers. I have been waiting for 9 weeks now. I got tired of making more sims...

[kees52]

Originally Posted by epa

its diffecult to get this driver to play low.
250 lts tuned at 20 hz .not verry small
if you punch the numbers from in the input screen,you cam play with the wizzard yourself.
click on the pic left bottom x to enlarge pic.

Thanks , I had also that same idea, a normal vented box was already 200 plus liters. but if I halve the vas then it get smaller, like a isobaric way and go low, but that is not a ppsl anymore.

high Sd and smaller VAS will work oke here.

thanks for your attemt I go play.

photo is the slot I did make for measuring.

[kees52]

Hi Epa

I have fill in the hornresp, I get lower spl, and I have change the VRC to 150 and get this,
not 20 hz without loss but 25 hz - 1 dB is there what is most of the time enough I think.

Afcourse if i did it the right way, your simulation is 95 dB?? did I something wrong.

the vrc is 150 I have lowered that after the test for as you see it and think this is the problem, maybe I have a old version of hornresp it is 21.30

thanks

[kees52]

How have I connect the speakers in a ppsl box, in fase or out fase. I have test the slot the woofers go from 19 hz to 29 hz in it, when as a ripole it go from 29 to 22 hz.

I measure with limp and use the output of the audio card I think I need a 10 watt amp for it to do good.


thanks

[djk]

That's odd, the Fs usually goes down a very small amount (I just ignore any change).

[kees52]

Originally Posted by djk

That's odd, the Fs usually goes down a very small amount (I just ignore any change).

maybe because it is open, it go down if complete box on it, but the speakers have already natural 19 hz Fs. or in a ripole I need to make it complete ripolo before that work.

[djk]

If you check several identical drivers the parameters will be all over the place.

However:

The (Qts^2)*Vas will generally be constant, as well as the Fs/Qts product.

[kees52]

There are a lot of interesting speakers for OB special the car woofers who have nice qts of 0.59 like this one.



Google Afbeeldingen resultaat voor http://www.pdfjungle.com/images/MTX-Audio-Portable-Speaker-Specifications-Sheet-for-MTX-Audio-RoadThunder-RT15-04-Portable-Speaker-PDF-Preview.png

[kees52]

Ohh ahh I had a old version of hornresp 21.30 the new one is give other results but not wht epa has, so what is wrong, and how do i interpret hornresp in a PPSL box.

Is it not better use a speaker with a lower vas? then the box will be smaller. it is quite big with this woofers, and I need two for a ppsl.

thanks.