Welcome, Guest. Please Login or Register
Decware Audio Forums
04/29/24 at 15:16:12 




Pages: 1
Send Topic Print
precompression in the WO (Read 13247 times)
gexter
Ex Member



precompression in the WO
10/31/05 at 15:46:04
 
Got something to think about.

One idea is a over sized precompression.
It just something to think about.


the other idea is a change of the layout of the WO


On fostexs web site they talk about the double bass reflex and some science and required sixth sense is needed to get somewhere.
Sometimes thing that should'nt work do! But you can't go wrong
by following all the rules.

can you double reflex a WO? I wonder what that would look like
or a wo with a built in precompression chamber.

As Hulk Hogan used to say" What are ya gonna do brother?"
Back to top
 
 
  IP Logged
60ndown
Ex Member



Re: creating a precompression chamber in the WO
Reply #1 - 10/31/05 at 17:57:50
 
i need a picture to understand what your talking about, or send me some of those drugs...that might help?
Back to top
 
 
  IP Logged
J_Rock
Ex Member



Re: creating a precompression chamber in the WO
Reply #2 - 10/31/05 at 22:28:51
 
i got it here: ( i think? )



1. is the front of the sealed cube with the ten inch subwoofer

2. is the normal 10 hole in baffle.
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re: creating a precompression chamber in the WO
Reply #3 - 11/01/05 at 01:12:16
 
BAHooOOOMMBAHooOOOMMBAHooOOOMM. Q>1, more like 2.5, is a bad idea.
Back to top
 
 
  IP Logged
djman37
Ex Member



Re: creating a precompression chamber in the WO
Reply #4 - 11/04/05 at 20:17:25
 
[quote author=gexter  link=1130777164/0#7 date=1130808541]ya go figure, I saw that a little late didn't I
Stupid bunny is whispering things in my ear.

like I said should have kicked brain in before posting

This can let people know that this is not a good idea just in case they come up with the same one , and what will happen if they waste their time in such a venture.

I am simply getting bored waiting for my plans.  

yesterday I almost installed my imperial in the attic of my garage.
I was not able to get it through the access hole in one piece.
I could'nt get the chainsaw to fire up so its safe for now


Gex [/quote]

I've about decided, you sir, ARE INSANE!!!
Keep up the 'out of the box' thinking though.
Back to top
 
 
  IP Logged
gexter
Ex Member



Re:  precompression in the WO Not a good idea
Reply #5 - 11/05/05 at 03:24:00
 
Crazy  Crazy!  Crazy is walking down the street with half a cantaloupe on your head screaming " I'm a hamster"  is crazy.
I am not crazy, just sanity challenged



Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re:  precompression in the WO Not a good idea
Reply #6 - 11/05/05 at 11:57:24
 
Gex,

I'm not sure that removing an informative thread is smart. I understand nobody wants to be associated with a failure, but having this kind info available for the future is what this type of forum site is all about. I think the idea has merit, but we can't "fool Mother Nature" or Father Physics either. The size ratio between the 2 volumes is a critical property that makes a 4th order cab work as well as it can.

My current understanding of what you are trying to accomplish with this concept is increased driver control. Like in the DB, some containment of the initial pressure could have a stabilizing effect on the cone movement. The ratio of the 2 volumes needs to be similar to the original to work well, but adding a secondary baffle, either in front or behind the driver could be very helpful.

Without some testing, though I wouldn't know how far away to place it or how big to make the hole. Someone with more time and money than I have will have to work out the details for us first. I think you should re-post your diagram and another showing some alterations which may be more practical. MNSHO    :)
Back to top
 
 
  IP Logged
Circlomanen
Ex Member



Re:  precompression in the WO
Reply #7 - 11/06/05 at 11:07:57
 
If you would make a backloaded WO, then the double chamber reflex idea is probably the way to go.
I would not want to try and tune those chambers with the added resistanse of the horn/port part.
Trick but probably a good way to go if you have the sim-software for it.

Johannes.
Back to top
 
 
  IP Logged
Circlomanen
Ex Member



Re:  precompression in the WO
Reply #8 - 11/06/05 at 11:15:49
 

Something like this.
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re:  precompression in the WO
Reply #9 - 11/06/05 at 11:56:11
 
Circlo,

Check the relative sizes. You've got to keep the Q around .7 for it to work over an extended range.

Gex,

Your second illustration is more likely to work. You're getting there! Keep going and we'll have a WO32, almost. Grin
Back to top
 
 
  IP Logged
Circlomanen
Ex Member



Re:  precompression in the WO
Reply #10 - 11/06/05 at 12:39:24
 
Quote:
Circlo,

Check the relative sizes. You've got to keep the Q around .7 for it to work over an extended range.


The double bassreflex gives a high loading over a big frequency range of the woofer by using the first chamber like a sealed chamber above the port tuning. (first port)
The second chamber works together with the first chamber below that tuning-frequency and is working like one big box tuned with the horn/port.
Back to top
 
 
  IP Logged
DirtDawg
Ex Member



Re:  precompression in the WO
Reply #11 - 11/06/05 at 13:27:56
 
Very true, but you will need enough air movement to actually load the second chamber. Bring up the tuning of the first port enough so that the freq is about an octave (or better 1.414 octaves) above the second chamber tuning. That should bring the ideal ratio back to the 2 chambers, I think. Grin
Back to top
 
 
  IP Logged
gexter
Ex Member



Re:  precompression in the WO
Reply #12 - 11/07/05 at 01:49:34
 
interesting  Circlomanen
so correct me if I am wrong here.
the ideal is having the port tuned higher by an octave as DD says and then loading the port/horn with it. You would first have to figure the tuning of the port/horn to get it right.
A horn can be loaded with a higher freq than the horn principle.

Slide the enclosure along a back wall that has substantial free space in both directions, stand the Modified WO on its face about 4-6 inches up .
the way you have it diagramed you could run in in stereo.  you would have a mono horn output out the bottom
I wonder in its configuration and location it would create the unwanted boom that is so hard to get away from.



I wonder if the drivers were closer to the ports so when it was stood up with the horn facing down the drivers were not so close to the floor.
Back to top
 
 
  IP Logged
Circlomanen
Ex Member



Re:  precompression in the WO
Reply #13 - 11/07/05 at 08:08:01
 


Something like this?! The circles are the drivers.

(it looks sad!)
Back to top
 
 
  IP Logged
Pages: 1
Send Topic Print