hey guys, im thinking of getting into some dB drags and ive read in the street classes you need the back seats to be able to click into there upright positions without being obstructed by any of the stereo components.

im thinking of building a "wicked one" from decware (big topic on wicked 1s) for my pulsar and i was wondering how much difference to the tuning it would make if i angled the front of a wicked one (the side with the mouth in it) apart from the obvious changing the size of the sealed section would this be detrimental to the sound/loudness of the box noticably?

also can anyone estimate what sort of numbers i could get out of a 24x36" wicked one with 2 soundstream spl12's running off 2 jaycar 800WRMS monoblocks in my pulsar hatch?

cheers.

angleing the mouth probly wont affect spl or sq much
but i think the wicked one would be better facing backward loading off the rear

well teh volume for the subs will be reduced so that will effect it somewhat

but as said, loading it off teh rear will work better

thanks guys

the only problem with loading it off the rear is that with the correct distance between the mouth of the box and the back of the car (15 - 18" from my research) the box will be halfway over the back seats and hence they wont fold up which is why i was thinking having it facing forward with the angled front would be better.

trism, do you know if the volume differences will be noticable? how much are we talking here coz if its only a small difference it doesnt really matter.

A well designed ported box will be louder. I would hate to see you waste your time.

the wicked one doesn't have any real design behind it anyway.

Huh???.

I would asume that you have built and used one?

there is no real maths behind it.

if you ask the designers of it, thats pretty much what they'll tell you.

it works reasonably well for what would have to be considered a "prefab" box.

So i take it as a no!!!

It's a horn, so any changes you make to the horn mouth can have very significant effects, there is alot of maths behind the design of a horn, principally around the horn flare rate and this is what you would be changing by tapering it. Although it's design is fairly generic as far as being specific to a driver, the horn design itself isnt.

Simple answer I wouldn't do it!!

i dont know where you read what you stated above but its not right.

as a general rule i have found rear loading 4-6'' off the rear of the car does the job very well.

having your port face forward for SQ wont sound that great and for SPL you wont achieve much of a score.




what sort of pulsar we talking about also?????.

How about you make one or actually listen to a properly built one using the recomended drivers. Just because it is flexible does not mean that it should be "considered prefab" pull your head out, being flexible actually proves that it is well designed!

I used a wicked one for subs i've heard before that sound poor in well built sealed and ported enclosures, in a wicked one there was a vast improvement both in terms of spl and sq.

In this instance however there are too many comprimises, I too suggest a well built and designed ported enclosure.

its not even a horn. Its a wave guide. Its prefab. A proper horn won't be able to be scaled down like the wo and won't only have dimensions to whole inches. Haha

You don't need to 'build and use' stuff... TheyDontWantMusic is an expert in many areas, just ask them

we know its not a proper horn more like a expanding port or as some describe it a "rubber port". When its scaled the ratios are kept the same, this is what makes it so flexible and thus a very good design.

make it with the angled front. It will make little to no difference. Of course the box won't work well at all forward firing anyway.

[quote name='BMWTurbo' date='May 14 2008, 12:22 AM' post='960114']
You don't need to 'build and use' stuff...

Really ??.

Well I must have wasted many years of my life doing just that.

I have built a few of these and they react vastley to change , so do ya home work when making changes.

My Advice build one play around with it and see what happens but what would i know!.

yeah i think il just leave the front square and make the bigger (louder) one (36x36) and not worry about putting the back seats up at all.


i read it somewhere in the "how to build a wicked one" thread on this site, cant find it atm but its somewhere in there, anyway the box would be hard up against the tailgate with the backseats up hence why i was gonna face forward, but i think im just gonna face it back anyway and take out the back seats, i think this will put me up to street max class (correct me if im wrong) this way i can also play with the distance from the rear to find the best in my car. ohthe pulsar is the n13 hatch in my sig.

thanks everyone for your input, ive been thinking about it and i think i will just have a play around with the box to see what its like, i can always go to a ported box later if i dont get the results, or if i decide i need the back seat lol...

does any one know what sort of numbers i should get out of the 36x36 one with my 2 spl12's and jaycar amps with it loaded off the hatch the right distance?

now i know its a N13 and that i have played around with these before.

below is a picture of a build i did for a guys N13 pulsar just over a year ago.

the subs are 12'' Faranhiet subs $100 each.
the amp is a 900wrms kenwood monoblock

box from memory was about 2.4 cube tuned to 35Hz the car did 142's all day long

so in my honest opinion i reckon you should just build a normal ported box for your car and bolt your amps to the rear of the seat and have the subs loading up and port firing back. with your gear i couldnt see it being a problem to hit 145's

Click to view attachment
Click to view attachment

but what sort of numbers to expect from a N13 using a wicked 1 would be hard to answer as not sure anyone has used one in a N13 pulsar before

with this setup should i use the soundstream recommended specs for the box or is there a good calculator i can use for the dimensions?
also how would i go about tuning the box to the cars resonant frequency as ive heard this helps with spl, do you know the resonant frequency of the pulsar? will this box still sound alright for daily listening? as this will still be my daily driver

thanks for all the help.

tune to about 45Hz for the pulsar and for daily listening it should sound fine. it wont win a SQ comp but it will sound good still.

for 2x 12's 2.4-3 cube isnt a bad start. basically try fit the bigest box in you can and leave enough room at the sides of the box and the rear of where it is going to load off for the port. so air flow can travel easily still.



hope that helps but i will leave it now for a couple of the other guys to give their advise also.



cheers billy

ok i think i got it mainly sorted now, ive modeled a 4 ft^3 box with a 150mm x 250mm port tuned to 45Hz in winISD, it puts out 100dB @ 57Hz with 1W @ 1m does this sound about right?

oh and just one more quick question, how much difference will it make if i have the port facing up and the subs loading off the hatch? coz im thinking of having the amps mounted to the top of the box with neons and stuff for show and i cant do this if the subs are there...

port facing up drops db's in the N13 pulsars.

in my misses pulsar i dropped from 148.1 rear loading, down to 146.8 when the port was loading off the hatch.

somehow you've managed to get that number 3dB higher than what winisd says for me

hmm, dunno what happened there, did you model it with 2 Soundstream SPL12's?

I think you missread what I said in italics (symbolising sarcasm) here...

Put away WinISD buddy it's not really going to help you.

yes, and I did it again, with the soundstream SPL12 specs that are already in winisd, and this resulted in 96dB 1w/1m at 57Hz.

anyway, this all means nothing.

oh ok, the version i got hasnt got the spl12s in it already so i used the specs on the soundstream site, they might be a bit different.