Welcome, Guest. Please Login or Register
Decware Audio Forums
12/20/14 at 19:46:21


Pages: 1 
Send Topic Print
JBL GT150 15 " subs (Read 14132 times)
db_audio
Ex Member



JBL GT150 15 " subs
12/01/05 at 02:43:01
 
OK, how about this...I have 6-JBL GT150 15's. I wanna built the wo and use them if possible...3 enclosures and use 6 subs. OR i huge wo and use 3 per side. any suggestions... thanks DAN
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #1 - 12/01/05 at 05:25:19
 
You could send me those 6 14s in exchange for an entire WO with 2 infinity 10 inchers, and amp and a capacitor.

Or we could all speculate...

Lunarlab is doing a massive WO array, i think 4 per side with 10s...
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #2 - 12/01/05 at 15:30:36
 
[quote author=db_audio  link=1133408581/0#0 date=1133404981]OK, how about this...I have 6-JBL GT150 15's. I wanna built the wo and use them if possible...3 enclosures and use 6 subs. OR i huge wo and use 3 per side. any suggestions... thanks DAN [/quote]

i built a housewrecker with older jbl 15s' it worked very well.seriously good bass and tons of it.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #3 - 12/01/05 at 17:42:36
 
I am in the process of building a wo for 2 JBL GTI 10's...but I also have those new 15's laying aroung and would like to put them to good use!
Back to top
 
 
  IP Logged
Braggi
Ex Member



Re: JBL GT150 15 " subs
Reply #4 - 12/02/05 at 02:52:19
 
Dan, have you considered Imperials?
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #5 - 12/02/05 at 03:00:00
 
not to sound dumb but i dont know what imperials are...sorry
Back to top
 
 
  IP Logged
Circlomanen
Ex Member



Re: JBL GT150 15 " subs
Reply #6 - 12/02/05 at 07:57:33
 

That is an Imperial!
Se Imperial on this website.http://www.decware.com/imperial.htm
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #7 - 12/02/05 at 12:50:52
 
holy crap...um...did i mention i wanna use this in a ford expedition? but...it might fit... thanks
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #8 - 12/02/05 at 13:18:34
 
Circlomanen

can you not flash those things around! I get all sad inside because I can't buid one for my house. Sad

Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #9 - 12/02/05 at 14:33:51
 
When you get the 10" WO done, you will forget all about putting all those 15s in your car. They won't be necessary. Grin
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #10 - 12/02/05 at 22:06:14
 
True true

which is why I suggested giving them to me! please?
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #11 - 12/03/05 at 01:06:51
 
I could give them...but then again...JBL would get pissed and i don't think that they would like it too much!  

I should be done with to WO this coming wed! I cant wait. From what you guys are telling me, my expedition is gonna come alive! ill keep you posted. I guess my main reason for asking about the 15's is I wanna get them playing and of course get them stuply loud...(I really have 12) - but was only gonna use only 6 if you guys had any suggestions about using them in a WO.

thanks again it gets bouring around here at times 'cause their is no one around here that comes close to having the knowledge that you do!
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #12 - 12/03/05 at 01:41:06
 
Twelve 15s? ???
That makes two Imperials, an iso-loaded HWK15, two Wicked Ones, scaled up to 54x54x21.
Some of us are dying to hear a scaled up WO with 15"ers in it.
You'll get right on that, right?  :D Cheesy Cheesy Cheesy Cheesy
Back to top
 
« Last Edit: 12/03/05 at 01:42:58 by DirtDawg »  
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #13 - 12/03/05 at 04:41:38
 
you hit the nail right on the head. that is exactly what i was wanting...a scaled up version of a WO...maybe 4 isobaric? OR we could get stupid with it and do an 8-15 WO (4 per side iso)...i dont know about you but im not scared of getting a little sawdust on me and try something...i just need a little help getting started!
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #14 - 12/03/05 at 12:12:46
 
My only problem with a four 15" WO is that I don't have a fork lift anymore. I used to have nothing but fun stacking my 350 lb folded horns up. Those were younger and more energetic days.

Last week I set my 2 iso-loaded 10" WOs up in a club for some friends and everyone (including me, a fairly old, salty crusted, PA tech type who has seen everything, I thought) was very impressed. It was the first time I actually heard them with live music. They had an old Peavey 400W/channel amp and the WOs really sound powerful sitting on the floor in a small club (about 350 seats).

This afternoon I'll be setting them up in a place more than 4 times larger. Since it is Jack's favorite "sounding" gig spot, I'm calling tonight the WO/Jack Acid Test. They will still have way more BASS than ever before, so I expect everything to be "all good". So far, I am very pleased with the 10" WO.

With 15"ers the size will be a concern. I have read about someone planning a 48" WO project using 15" drivers, but never a follow-up thread.  I know scaling all 3 dimensions for a 15" comes out about 54" X 54" X 20", but I don't know if it's necessary to scale in 3 dimensions for a great sounding box. My plans, in the spring, are to build a set of Imperials and a 48" X 48" X 18" WO using a surplus of JBL E140s I have laying around from the old days. As yet, I've not done it.

My point is that you are sort of on your own, but with an audience of many "Monday morning armchair quarterbacks" ready to tell you what to do. I hope it all happens soon so we can start some history here.

Some old threads:

http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=Wicked;action=display;num=109...

http://www.decware.com/cgi-bin/yabb/YaBB.cgi?board=Wicked;action=display;num=109...


Looks like BigAir is the only one to actually build a 15" WO and post pics, but notice the radically angled baffle board.
Back to top
 
« Last Edit: 12/03/05 at 12:34:18 by DirtDawg »  
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #15 - 12/03/05 at 15:45:19
 
clamshelled h.w = 4 drivers
clashelled wo = 4 drivers
"

 db= 2 drivers
???
do it all again Cheesy

or some imps?
please build a 15 clamshelled wo scaleing all 3 dimensions

if the ts are anyhweere near  x max 5 mm and qts .35 how bout a 15 inch wo32?
Back to top
 
« Last Edit: 12/03/05 at 15:46:31 by 60ndown »  
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #16 - 12/03/05 at 16:01:27
 
For SPL-clamshelling or iso isn't going to help, just raise the level of power needed to acchieve a certain SPL.

The only benefit for iso is decreaseing vas bay half and increaseing power handling before distortion.

with 12 15s though, if you have the power clamshell away...
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #17 - 12/03/05 at 16:02:11
 
And I doubt JBL would care too much if you loaned me 2 15s...



prolly wouldn't even notice.
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #18 - 12/03/05 at 16:12:16
 
[quote author=60ndown  link=1133408581/15#15 date=1133624719]please build a 15 clamshelled wo scaleing all 3 dimensions [/quote]

What the  :o is this?
My very first post on this forum, I asked the same question and you told me not to bother. Have you become totally light headed today or have I finally worn down your resolve. Smiley
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #19 - 12/03/05 at 16:14:53
 
Lets hope 60's resolve is okay, he saves many of us form horrible experiments by saying:

"Build it exactly as the plans show and load it with suggested drivers and it should sound great?"

*I like how he always puts the question mark, like don't you agree*
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #20 - 12/03/05 at 16:46:41
 
[quote author=60ndown  link=1133408581/15#15 date=1133624719]please build a 15 clamshelled wo scaleing all 3 dimensions [/quote]

Maybe I should say "Who the Hell is this and what has he done with 60?"


Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: JBL GT150 15 " subs
Reply #21 - 12/03/05 at 16:48:45
 
[quote author=J_Rock  link=1133408581/15#19 date=1133626493]Lets hope 60's resolve is okay, he saves many of us form horrible experiments by saying:

"Build it exactly as the plans show and load it with suggested drivers and it should sound great?"

*I like how he always puts the question mark, like don't you agree* [/quote]


So true! I pound that drum frequently, but not like the Maestro.
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #22 - 12/04/05 at 01:39:32
 
lol, you guys Embarrassed
i dont know what it is, my experiences so far with building steves desighns are that they work, very well, all of them.i wanted good quality bass and loud, and i got it.but dirt reading some of your VAST experience leads me to believe you are in a leauge of your own. how many people have had the oppertunity to play with the rigs you have and over the period of time?..not many i bet. im sure when you move from 2 watts in a room to 20,000 in an arena things must change? everybodys enthusiam  for the 'excess' when it comes to bass, has obviously rubbed off on me- "thanks" Roll Eyes. im 42 next year and i have built 6 subwoofers this year and an i.b install in my car Cry  if you guys dont stop talking about insane bass rigs that make your neibour wanna vomit when it hits low and makes yer beer froth over as you walk by the sub, im going to be unable to resist building more next year, and im really not sure my wife can take it? i dont post as often nowdays cos both my in door and in car systems satisfy for now? but i frequently read all your posts and laugh and drool and wonder ??? thanks to all of you bassheads for not leaving me out there....here, on my own..................... Cheesy  i wonder what 10,000 real watts on a pair of some of these modern subs (3,4,5000wrms capable) in a modded wo would feel like? or a hw Cheesy  i would love to have a sub make me vomit @20 hz, seriously i might not wanna do it twice but id love to feel that much pressure that low Grin
Back to top
 
« Last Edit: 12/04/05 at 01:40:44 by 60ndown »  
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #23 - 12/04/05 at 01:44:30
 
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #24 - 12/04/05 at 01:53:27
 


and mine

Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #25 - 12/04/05 at 02:05:36
 
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #26 - 12/04/05 at 02:11:16
 
Your original statement still stands as good advice 60.
I have taken on the same stand, on your first build anyway!
DD has loads more experience than I and I am sure keeps up on his stuff. I mean what else has he to do during the day Smiley ( thats a joke)
After I screwed up steves subs I took your advice 60 and life improved to the point where I started modding after I knew what it was supposed to do.
DD keeps my head on my shoulders and helped me from making some time consuming mistakes that would have frustrated the heck out of me.

both you guys are from differant worlds but none the less, your rocks in mine.

oh ya
Since when is your present car system based on steves design 60....... thats all you!
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #27 - 12/04/05 at 03:51:13
 
"i.b rules - boxes are for fools"

my new motto Cheesy
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #28 - 12/04/05 at 06:33:39
 
I have an I.B. in my wagon and it sounds awsome but it just does not get loud enough for the times a guy likes it loud.

Any other sub takes up way too much room to equal it in SQ and low extention and  that includes Decwares.

It is built into the rear well of the station wagon. after my alpines were stolen I did not want my system out for people to see.
I recessed an ADS sub plate and covered it with material to stealth it. you would never know it was there. all my other crossovers and amps were recessed into the same well as well.

anyway I am screwing up this thread so later!
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #29 - 12/04/05 at 07:08:24
 
AP is the new IB.

Aperiodic is the new Infinite Baffle.

I am thinking bout doing an AP in my car...
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #30 - 12/04/05 at 16:32:31
 
[quote author=gexter  link=1133408581/15#28 date=1133678019]I have an I.B. in my wagon and it sounds awsome but it just does not get loud enough for the times a guy likes it loud.


[/quote]

my amp is class d and puts out about 6oo wrms (stock electrical)and the 12" sub takes 500wrms has an fs of 18....yes 18 and an x max of 24.2 mm. it gets loud and low Wink

http://www.soundsplinter.com/specs/rlp12_specs.htm
Back to top
 
« Last Edit: 12/04/05 at 16:33:14 by 60ndown »  
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #31 - 12/04/05 at 16:41:55
 
you have an expedition right, you wanna slam 3 WOs with 15 in there, without the back seats I bet you can do it.

What I would do first is to measure how wide the back is at the narrowest points, so between the wheel-wells.  Whatever that measurement is, make the WOs that measurement, Y, YxY x 19 or so.  then take the 3 WOs and lay them at angles pointed towards the front or back, whichever is louder.

Otherwise, set the WOs up in a triangle, one on bottom and the other two tilted on top.  I don't know if you will have the heighth though.

I drew some crappy pictures, although my mastery of Paint is Increaseing ten-fold daily.



If you go the route of angleing them towards the fron or back, try to angle them as much as possible, or as close to flat.  This will give you more air path above them, although you might wanna try different angles cause that could effect performance.
Back to top
 
« Last Edit: 12/04/05 at 16:46:27 by j_rock777 »  
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #32 - 12/04/05 at 16:44:07
 
also, ported version for SPL:



Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #33 - 12/04/05 at 22:23:42
 
thanks  J_Rock
I never saw the pictures of the ported version. It was not what I thought it would be.
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: JBL GT150 15 " subs
Reply #34 - 12/04/05 at 23:27:55
 
port schmort Lips Sealed
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #35 - 12/05/05 at 04:56:18
 
GEX...you know what me and my wife were thinkin about how to port it. we came up with very close to what the pics show...but...im like naw that couldnt work because of the phase difference...but now you show pics and i guess it does work...
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #36 - 12/05/05 at 05:12:58
 
i bought my wifey a new expedition last week and im keeping her old one! which has a ton of gear in it already! i had 9 of the 15's in it (LOUD) but took it out 'cause we WERE gonna trade it...we didnt! YEAH!

my point is i wanna make this thing just stupid loud...louder than the 9 i just took out. Im hoping that the Wo is the ticket!

if i remember correctly my 9 15 box is around
50W X 33H X 30L

I figured i could have them firing toward the roof, they might load off the roof pretty good...just thinking.

oh yeah, those drawings wernt TOO crappy! LOL!
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #37 - 12/05/05 at 05:13:04
 
from what I ahve read so far on the porting of the WO is it is good for SPL only.
And I agree on the phasing and 60's view of the whole thing.
but........ I think its possible to make it close to the SQ with enough trial and error ( mostly error )

Sometimes the science of it is not the whole story.
also lack of funds makes a person try the silliest things....

I just bought an plate Amp today for really cheap out of the box.  it even came complete with a sub and box. Cheap box, cheap DVC sub. decent 100 watt plate amp. cheaper buying the whole thing than just the plate amp.


strange how things work out sometimes
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #38 - 12/05/05 at 05:23:04
 
If your thinking stupid loud and stupid good don't take the chance on modifications. you have the area and the power to make the WO put out.
If you do the J_Rock tilted sub idea I would fire them off the roof also, but tilt them toward the back on your first trial run.

Excess is fun but rarely practical. But what kinda fun is practical?
Hey!  that could be my new tag line

too bad I am getting to practical  :(  thats just no fun!!   Wink

Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #39 - 12/05/05 at 05:29:31
 
if you measure the distance from the drive to the port opening in the horn mouth you get 1/4 the wavelength of the highest freuency total wave addition occours at.

So you measure, then tune the box to that frequency.  Not only making the front and back waves add, but also oncreasing efficiency at the frequency at and around which they add.  If you were gonna go real big you could aim to tune the entire thing at your vehicles transfer fucntion frequency to get even more bass.

I would suggest just 3 WOs though for sure.  port them if you can figure out the math and what not otherwise just let them sealed.

My WO has increased my 2 drivers rated sensitivity by 19db at least.  (Drivers max power = 2^[X]; X x 3 = Driver's proposed SPL at max Wattage.  My wo puts out 19 db more than that SPL at half volume on the dial. No way to test further...)
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #40 - 12/05/05 at 05:33:32
 
If you could give me the width of you epedition I could figure out the WO chamber's and the original designs's ported frequency.  and then design the 6th order BP with smae chambers and front port to create what would be the supposed correct port.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #41 - 12/05/05 at 05:48:10
 
i have a tightly squeezed 50" (max width)
Back to top
 
 
  IP Logged
gexter
Ex Member



Re: JBL GT150 15 " subs
Reply #42 - 12/05/05 at 05:50:19
 
(transfer fucntion frequency to get even more bass. )

I have not heard that term before, are you talking about wavelength, or what exactly so I don't have to guess.
even a link to where you got the terminology would be good.

I had to learn so much stuff over the last month or two I have holes in my knowledge. and my life keeps interrupting me on top of that.

thanks
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #43 - 12/05/05 at 05:57:10
 
ok but doesnt the port need to be tune approx 5-10hz highter so that they dont cancel...or would you have to have the ported camber 1/16 wavelength if you have 1/4 coming from the mouth? im just thinking of distance and the timing...i havnt done the math yet.
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #44 - 12/05/05 at 12:30:48
 
hold the thought bout port frequency, I just remembered something. SO I gotta check something else.

Transfer function is kinda like your entire car's resonant frequency. The problem is that as power goes up the cars resonant frequency goes up too, hence you get a function of resonant frequency vs. power output.  Kinda like this:

With my subs barely playing say at 45 hz, my car rattles like all hell and there is a noticeable increase in output going from 35 to 50 at 45 hz.  My car resonantes there at 50 w or whatever.  If I crank my WO all of a sudden my car doesn't resonant at 45 as much, the noticeable uncrease is at 55hz.  

At least its something like that.  I normally say resonant frequency of the vehicle but I get slack from a different forum for saying that...
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #45 - 12/05/05 at 12:33:33
 
determining the frequency to port it at will be math stuff, but you defineatly wanna figure out when the waves add completely and tune to that frequency.  In normal 6th order BP you tune the 2 chambers 5-10 hz apart to get a large peak between the two tuning points, however if you can figure out exactly the frequency that both outputs(front and back of cone) sum you can then une to that frequency.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #46 - 12/05/05 at 15:20:20
 
cool...thanks. ill try to do some of the math today at work...unless youve already done it
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #47 - 12/05/05 at 18:21:03
 
the problem is with the horn/port thing. I am not sure exactly how it works, seeing as how it is flared port.

There are people on another forum I am talking to who actually know how to model exponential ports so I am talkign to them.

I figured out the chambers rough sizes though for a scaled up to 50 inch square.  the rear chamber(sealed) is 393.75 square inches and the front chamber is 312 square inches.  thats square so whatever the heighth is minus driver displacement...

Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #48 - 12/05/05 at 21:56:22
 
what other forum are you on?
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #49 - 12/05/05 at 22:05:07
 
www.diyaudio.com, its currently down for the count.

I got a picture labeled with the areas and lengths of the WO scaled to 50 inch square.



I also posted somewhere else, can't remember, asking how to model the exponential port.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #50 - 12/05/05 at 23:44:22
 
that might work...cant wait to do the build
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #51 - 12/06/05 at 00:58:55
 
the thing I am worried abotu would be the length of the port may lower tuning way down...not sure.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #52 - 12/06/05 at 02:55:23
 
every setup has been loudest at 37 to 38 hz. weird cause i tested and retested and found res. freq. to be right around 46 hz
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #53 - 12/06/05 at 03:01:29
 
my car is weird liek that too, resonant around 44 hz, yet loudest in 60hz region.
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #54 - 12/06/05 at 14:47:37
 
I keep getting mixed coments about the WOs actual box type, some people say its clearly a horn, but its small size makes it a lesser horn(in efficiency). Others say it is a 4th order BP with an exponetial port.  

If it is a horn, when you stack them you increase efficiency nto only by 4 db for doubling power, but by 6-9db for some reason.  



Another option for porting would be out the front, rather than worry about the horn path at all, simply vented out the front would allow you to focus on the summation of the waves.
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #55 - 12/13/05 at 01:00:20
 
well j_rock...ive finally got off my arss and started the build!!! 2of them will fit quite nice but fitting a third one is gonna be hard...but im tring it ayway!! thanks for all your help! -dan-
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #56 - 12/13/05 at 01:01:25
 
I demand Pics!

Are you building them all at once? or building one to see how it performs than adding more later?

I really wanna come see them too!
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #57 - 12/13/05 at 15:54:29
 
ive started on one...but all 3 will be built before the installation and i test and tune everything... will send pics soon prob this weekend!
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #58 - 12/26/05 at 21:12:26
 
ANY Updates?
Back to top
 
 
  IP Logged
Learner_UK
Ex Member



Re: JBL GT150 15 " subs
Reply #59 - 01/15/06 at 10:14:54
 
Where have you got all these JBL drivers from??!
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #60 - 01/30/06 at 04:01:53
 
sponsorship...team jbl
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #61 - 01/30/06 at 04:47:52
 
thats all we get? no pics?

Well, at least you are back on the forums!
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #62 - 03/01/06 at 13:13:45
 
Wow! what a long few months...no play time - just work all the time.
UPDATE: Good news...I have a wo about 90% complete for 2 JBL GTi 10's. I wanted to see how the 36" model sounded so i can compare the larger ones for the 15's. i will post pics as soon as i get a new cable for the camera. -dan-
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #63 - 03/01/06 at 20:49:30
 
I was just thinking about how I was gonna have to track you down and force you to finish. lol.
Back to top
 
 
  IP Logged
bassboy
Ex Member



Re: JBL GT150 15 " subs
Reply #64 - 03/03/06 at 02:34:27
 
Hi J, I saw some of your posts in the other forum and some people seemed more intent on  questioning the original design of the WO than answering the question you asked.  People that should know better, but they have their own stuff to sell, I guess.

I did a google search on exponential port and surprise, surprise, I didn't find much.  Maybe people know about them and are calling them something else, but there's not too much info on that particular search.  These are my observations based on listening to a WO and conventional horn theory.  Let me begin by saying I may be completely wrong and welcome comments and critisism.

The WO is NOT a horn by definition, at least not when used as a subwoofer.  Then gentleman in the other forum was right, by definition, this thing should not be able to go any lower than about 70, and that's if you stick it in the corner.  If you stick it in the middle of the room as a coffee table, it shouldn't be able to go lower than a few hundred hertz.  That would mean that when we cross it over at 80, we should be theoretically listening to absolutely nothing.  Is that the case?  Of course not.  I'm just guessing here, but I think most WO's are flat down to at least driver fs, regardless of room position.

So what is going on?  I have read at least 3 times in different articles about bass horns that until they get about 5 feet long they are not working as horns at all.  Not once did they mention what was going at at this length, the general consensus is just that it needs to be bigger.  This is why I believe Steve only scales in one dimenstion.  To elongate the horn (flared port, exponential port) too much would make it act like a horn, effectively making it useless as a subwoofer.  I can't prove that and I certainly am not going to build one to prove it won't work.

The flare contour or expansion rate does not seem to matter nearly as much as a real horn.  For example, Steve's corner horn is also much too short to theoretically do what it does, so it must also be a flared port, although it increases dramatically faster and ends with a much larger mouth.

So what is important?  In my opinion, based on absolutely nothing, it appears that a flared port should begin with a throat roughly the same as a corresponding real horn would have.  It should increase in surface area and length, to a length of not more than 4-5 feet and a mouth of no less than 5x throat area and I don't know about mouth maximum area but using the cornerhorns as a reference it should be able to get pretty big.

As far as porting this box, I do not think the gain will be worth the consequences.  I believe that raising the low frequency of a subwoofer is a crime tantamount to murder.  Just my opinion.

So please bring your critisms, as I would like to better understand this type of box.  I know my theory doesn't make a lot of sense but remember that by traditional theory this box used as a subwoofer coffee table in the middle of the room should have close to 0db output.
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #65 - 03/03/06 at 03:34:15
 
Basically the main thing I think we need to realize, is that we don't know exactly how the WO works so well.

I am with you in the fact that it most certainly is not a simple 4th order, and it is defineatly not a simple horn at the frequencies it is being used.


I think you should start a different thread also, because I am sure this thread doesn't need this discussion, but the forum as a whole does need the discussion.
Back to top
 
 
  IP Logged
bassboy
Ex Member



Re: JBL GT150 15 " subs
Reply #66 - 03/03/06 at 03:42:36
 
The reason I posted here and not a new thread is because this guy is considering building 3 upscaled models with ports.

My first point was that I don't think upscaling is a good idea.  The second is that I don't think ports are a good idea.

That's all I was trying to get across.
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #67 - 03/03/06 at 03:58:02
 
Well, actually in the end here he decides to build 3 simply scaled to fit the driver.

And he decided against porting I believe.

I thought you were just trying to strike up a good conversation about design other boxes similar to the WO or unraveling the "Mystery" of why the WO works.

My bad!

Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #68 - 03/03/06 at 13:17:23
 
Final versions will be up-scaled to fit the 15" driver...NO ports...and the only reason I wanted more than one WO is first is I have more than enough drives to do this with! second reason is I was thinking that I could achieve a decent amount of coupling. These are for a expedition - not a house sound room. I have a heck of alot of experience in box building and design but I wanted to experiment with something a little different...thanks -dan-
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: JBL GT150 15 " subs
Reply #69 - 03/03/06 at 15:46:45
 
Just drop us a line as soon as you have pictures or if you are going to be at any car audio shows!
Back to top
 
 
  IP Logged
db_audio
Ex Member



Re: JBL GT150 15 " subs
Reply #70 - 03/03/06 at 22:23:44
 
ok. as much as i am working, i really dont know if ill be able to get to Daytona (SBN) this year...darn-it! im upset about it but i guess you have to work so you can still play a little. i promise that i will keep everyone updated! -dan-
Back to top
 
 
  IP Logged
Pages: 1 
Send Topic Print