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Finally, some action... (Read 44209 times)
Adrian D.
Ex Member



Finally, some action...
05/17/06 at 12:57:21
 
i've had my mind set on building a db-10 out of 1inch mdf.
what the heck, someone built the wo out of 1inch mdf, the db10 needs something similar.
today i visited the shop where i bought the particle board for my first db build and they have 1inch mdf, but only on order...1 day waiting time Cheesy
i plan on taking my time, although they deliver the panels pre-cut to the sizes i want. good glue, good screws, lots of patience. no silicone this time. i'll probably use wood glue mixed with mdf dust for the seams. i want to put a plexiglass top lid and paint the inside of the box... Cheesy i wonder how thick should the plexi be ?
i'm working out the maths today. i plan on keeping the actuall baffle the same size and keeping the same distance from the face of the woofer to the panel with the 45 deg cut (panel F).
that should decrease the  volume the vented part of the box. something like mounting with magnet in vented, but i don't think 1/4" thicker would decrease the volume by much , so thicker material won't hurt. no panel flex this time. HARDCORE db10.
if the shop delivers the panels friday, i'll probably start working on sunday. this will be a weekend project, since i'm in the last month of the school year.

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60ndown
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Re: Finally, some action...
Reply #1 - 05/18/06 at 02:23:37
 
hopefully you will have a new amp (thanks 2 jet) to power the 'improved' deathbox?
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gexter
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Re: Finally, some action...
Reply #2 - 05/18/06 at 02:54:16
 
don't use wood glue mixed with MDF dust for the Seems.
use a gorilla glue or liqued nails instead.
unless its really compressed it will be week.

The plexiglass lid should be okay at 5/8 mimimum at the size. anything over is better of course,if your going with 1" MDF you may as well use 1" plexi if you can get it.
use a very sharp drill with a weak pitch to prevent cracking and go slow to prevent melting

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Adrian D.
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Re: Finally, some action...
Reply #3 - 05/18/06 at 13:14:31
 
jet added me in his Y! messenger list...
if i won't find him there, i'll surely find him here..
gex, i've planned about using 1" plexi. now i just have to find it.
i oredered panels to make me ping-pong table. but the whole db and table didn't fit into one mdf board. i had to give up the panel on the top lid with the cutout. anyway, i ordered the top lid, just in case i won't find plexi.
mdf will be here tomorrow. i'll start work asap. with pics this time Cheesy
i still have to find glue...i'm going today to the depot, to check out some glues. friggin glue, i don't know i can find liquid nails or gorrila glue over here. is liquid nails something like a nicely flowing glue ?
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Bob
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Re: Finally, some action...
Reply #4 - 05/18/06 at 14:47:27
 
Here you go Adrian. Not sure the policies regarding online ordering overseas, I wouldn't think It'd be a problem though.

http://www.rockler.com/ecom7/findprod.cfm?Cat_ID=545&DID=6&ObjectGroup_Id=217&fi...

Here's the main site for GorillaGlue, click "order online".

http://www.gorillaglue.com/gluefinder.htm#

Hope this helps,
Bob

p.s. I didn't know they had Gorilla Tape too...... hmmm sealing plexi with tape might be better than the glue, since the glue expands. The expanding may be just uncontrolable enough it might not look pretty.
Actually the tape may expand too?  ???
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J_Rock
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Re: Finally, some action...
Reply #5 - 05/18/06 at 15:09:22
 
I would use wood glue to join the MDF since it is made out of wood.  Then to join the PLexi to MDF, I would rabbit a slot for the plexi to slide into, and fill it with epoxy.  SLide the plexi in and your done.

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Jet-Lee
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Re: Finally, some action...
Reply #6 - 05/18/06 at 15:42:11
 
You Got PM, duder.

I would pre-drill/counter-sink holes in the Plexi, then use weather stripping and screw the plexi into the wood. Another method I've used, but isn't as pretty, is the same pre-drill/counter-sink, but put a bead of silicone sealant on the wood and let dry, then screw the plexiglass down cinching the silicone and sealing it.
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #7 - 05/18/06 at 16:35:38
 
i'll have to ask about plexi tomorrow.
if i manage to find plexi (and at an affordable price) i'll use some kind of sealing tape.
my dad said he knows someone who worked with wood al his life, and has wood glue, the one made out of bones  :-*
i also have to talk to a guy that has a router, to round-over the halfmoon.
thanks Bob, but such a small pack can get 'lost' during shipping. guess i'll have to stick with that wood glue made out of bones  :-* Kiss
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phd5000
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Re: Finally, some action...
Reply #8 - 05/23/06 at 00:32:25
 
ebay has 1" plexy.......
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Gexter
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Re: Finally, some action...
Reply #9 - 05/23/06 at 04:44:48
 
[quote author=Adrian D.  link=1147870641/0#7 date=1147966538]i'll have to ask about plexi tomorrow.
if i manage to find plexi (and at an affordable price) i'll use some kind of sealing tape.
my dad said he knows someone who worked with wood al his life, and has wood glue, the one made out of bones  :-*
i also have to talk to a guy that has a router, to round-over the halfmoon.
thanks Bob, but such a small pack can get 'lost' during shipping. guess i'll have to stick with that wood glue made out of bones  :-* Kiss [/quote]


gorilla tape! thats cool, never seen it but now I'll be lookin.
Natural wood glue will be fine on tight wood seams.
Gorilla glue and its lapages brother does a good job of filling small voids and bonds more than just wood.
I am rather fond of J rocks Plexi solution, you do not have to worry about drilling it.
Most people make a mess of it the first time around. One small fracture can compound in a short time.
at 1" plexi the odds are in your favour.
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Adrian D.
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Re: Finally, some action...
Reply #10 - 05/23/06 at 07:08:43
 
ebay is out of reach for me.
i'll ask an installer over here about plexi. i really want to find some.
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Bob
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Re: Finally, some action...
Reply #11 - 05/24/06 at 13:13:27
 
Tempered glass is pretty cheap. Has anybody ever done that?
Fairly strong too. Drilling holes would be out of the question.
But routering a channel in 4 pieces of wood, like a picture frame, but a channel instead of a rabbit grove, filling the channel with sealer, and stapleing the wood together. Then you could screw the wood frame to the box. I did this on the glass door of my equipment rack (no pics yet) and is very sturdy.

1X2 oak lumber, some sealer, and the glass is all you'd need...

Bob
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Adrian D.
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Re: Finally, some action...
Reply #12 - 05/24/06 at 13:40:20
 
good one Bob. frigging school, i still have to study for the sucky classes, like biology, french...
i have no time to begin. Sad
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #13 - 05/27/06 at 14:43:37
 
i tested a new position in the room today. facing the back of the room. opposite direction to where my head is facing. in the same corner where it was untill now, only i took the db-12 away, since i'm going to be switching to a single sub "setup"
it sounds more 'natural', maybe a bit faster.
i can't wait to try the new box.
i didn't start work because a friend of mine found a few people that wanted speakers, so i've been working on other boxes. i saved a few $$ and ordered a sub similar to J_Rock's Dayton HFs but it hasn't arrived, yet. more excursion, dvc 4 ohm and higher efficiency.
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J_Rock
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Re: Finally, some action...
Reply #14 - 05/27/06 at 18:56:55
 
what sub did ya get?

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Adrian D.
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Re: Finally, some action...
Reply #15 - 05/28/06 at 04:34:08
 
this is it.
should be here next saturday.
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J_Rock
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Re: Finally, some action...
Reply #16 - 05/28/06 at 05:03:33
 
Did ya get one or two?  and did you pay the price on their website?
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #17 - 05/28/06 at 06:40:45
 
1 piece, 170$. shipping done by a friend. he's currently in the us. should be here june 3 or june 10.
no shipping tax ftw ! Kiss
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #18 - 06/10/06 at 19:12:51
 
update :
i got all the round cuts done. i bought the panels cut, so i didn't have to worry about that.
i built the insert today and 3 panels of the outer box.
i still have to pay a visit next week to a carpenter to get the edges of the half-moon rounded.
unfortunately i got pawned twice Sad
the shop said they had 25mm thickness. upon measuring the panels home, i saw that the mdf was exactly 1inch thick (25.4mm). so now, the insert won't fit inside the outer box. sanding time !
my jig-saw played me a nasty trick. when i tried to do the 45deg cut, the blade wasn't cutting straight and it messed up the edge. fixed it with some glue. i had to do that cut with the handsaw and the use a wood rasp to get it right.
should have build pics soon. i just need to borrow a digital camera.
i still haven't tracked down some plexi.  :(
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J_Rock
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Re: Finally, some action...
Reply #19 - 06/10/06 at 19:49:41
 
Adrian, how much plexi you lookin for?

I got a couple small sections of balistic Plexi used in Cop Cars.  a little sqare about 12 x 12.  Only problem is they are really scratched up.  Not to many deep scratches though, so if you wanted to sand the piece till its smooth you could I am sure.

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Gex
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Re: Finally, some action...
Reply #20 - 06/10/06 at 22:37:58
 
Adrian
got any ice rinks nearby? I acquired some heavy plexi called puck board. Once it gets scratched up they replace it. Cleaning it up is not to hard if the scratches are not to deep.
it might be thick enough, If you want to know how thick mine is I can let you know next week when I get home. I recycled it for a window in my shed that is made out of scrap lumber.
It is at least 1/2 inch thick

Just a thought
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #21 - 06/11/06 at 06:57:27
 
J. and Gex,
i'm looking for something i can use as top lid.
i'll call tomorrow a local installer to see if he could help me with the plexi issue. if by any chance i can't find some plexi, i'll send one of you guys some $$ to buy a couple of pieces if you have the time.
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Gex
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Re: Finally, some action...
Reply #22 - 06/11/06 at 16:12:55
 
Adrian
Let me know the exact size and thickness and I will see if I can find something that will cost you nothing.

If you can buff scratches out I may have something.
My contact at the rink is in another job but I will still look around.
I can't guarantee anything but I will ask around in the next couple days, meanwhile keep looking anyway.

You already know I am not comfortable taking other peoples money. So if I can find something for nothing then I don't mind shipping it at my expense
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #23 - 06/13/06 at 12:18:41
 
i called the local installer. i'm making the plexi shop a visit today. i'm going to order the panels.
i'm thinking about putting the plexi lid just like i would mount an mdf lid (on top of the box) and not router a small canal in the mdf for the plexi to fit in.
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #24 - 06/14/06 at 12:51:33
 
build complete !
although during tuning only 4 screws secure the lid (out of 20) and the insert isn't sealed in.
i just pushed the insert to the top of the half-moon. this way, the sealed chamber size is the exact volume the manufacturer recomended me.
half-moon rounded nicely. magnet in vented.
first thoughts (only 2 songs played)
tight. loud (louder than the 2cf box i used to break-in the sub). as for how low it goes, it will take some time to re-play all the songs i know. i'll be checking for port noise in the months that will come as i finally finished this school year and i'm in vacation. it's crossed a lot higher and the anoing moo-ing (remember the thread ?) seems to be reduced.
i still haven't played with the x-over. it's at the same setting i used while break-in. ~70hz.
soon to come : pics and comparison to the infinity - db10 combo.
i gave up the plexi idea. 40$ for the top lid is a bit too much  >:(
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60ndown
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Re: Finally, some action...
Reply #25 - 06/14/06 at 13:39:39
 
[quote author=Adrian D.  link=1147870641/15#24 date=1150285893]build complete !
although during tuning only 4 screws secure the lid (out of 20) and the insert isn't sealed in.
i just pushed the insert to the top of the half-moon. this way, the sealed chamber size is the exact volume the manufacturer recomended me.
half-moon rounded nicely. magnet in vented.
first thoughts (only 2 songs played)
tight. loud (louder than the 2cf box i used to break-in the sub). as for how low it goes, it will take some time to re-play all the songs i know. i'll be checking for port noise in the months that will come as i finally finished this school year and i'm in vacation. it's crossed a lot higher and the anoing moo-ing (remember the thread ?) seems to be reduced.
i still haven't played with the x-over. it's at the same setting i used while break-in. ~70hz.
soon to come : pics and comparison to the infinity - db10 combo.
i gave up the plexi idea. 40$ for the top lid is a bit too much  >:( [/quote]
congratulations, i recently crossed my sub over @ abut 55hz, very nice, try it some day, also i never understood people mounting subs backwards? listen to it for a few weeks like it is and then reverse the sub for a few weeks and see if you can hear the difference?  plexi glass is for show offs, plain mdf is for audio enthusiasts!
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Lee in Arkansas
Ex Member



Re: Finally, some action...
Reply #26 - 06/14/06 at 13:44:07
 
[quote author=60ndown  link=1147870641/15#25 date=1150288779]
i never understood people mounting subs backwards? [/quote]
It increases the volume of the sealed chamber and provides better cooling of the motor structure.
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Adrian D.
Ex Member



Re: Finally, some action...
Reply #27 - 06/14/06 at 14:08:56
 
putting the magnet in vented is like lowering the insert. but you don't get the same effect as moving the insert over the port.
i moved the insert lower. right now it covers about 1" of the port. still can't decide between covered or uncovered port. it seems to go lower covered, but it's not as fast and accurate as uncovered.
this decision is going to kill me. i really like the look of the uncovered port. i wish i had a spl meter Sad.
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Lee in Arkansas
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Re: Finally, some action...
Reply #28 - 06/14/06 at 15:08:04
 
wal-mart, $30.
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60ndown
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Re: Finally, some action...
Reply #29 - 06/14/06 at 18:40:06
 
[quote author=Lee in Arkansas  link=1147870641/15#26 date=1150289047]
It increases the volume of the sealed chamber and provides better cooling of the motor structure. [/quote]

yea but the thing i dont 'believe' is that the sub moves equal amounts of air both ways, try bailing out your sinking boat with an inverted bucket Roll Eyes
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Lee in Arkansas
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Re: Finally, some action...
Reply #30 - 06/14/06 at 19:15:10
 
It doesn't move the exact same amount of air, it also doesn't move it in the same pattern. That inverted bucket is a good example. The front of the cone makes a pressure wave, while the back is more of a dispersion, by shape. What happens when you put an inverted cone into water, it pushes the water aside. Turn it over and it cups it. I see your point.

It moves almost as much air, slightly less because the front can use the space over the VC, whereas the back can't. Also, can't forget the baskets issues with airflow.

Now think about it like this....
Which puts more equal pressures on the cone, firing the front(has more 'pressure' as we've described) in a perfectly square empty space, or into a perfectly square space with a pice in the middle that covers the cone and half doesn't? I'd that 'obstruction' be on the 'weaker' end of the speaker, so as to raise the power handling of the driver. Don't forget that air flowing over the motor keeping it cooler.
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Lee in Arkansas
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Re: Finally, some action...
Reply #31 - 06/14/06 at 20:25:08
 
Someone correct me if I'm stupid and don't know what I'm talking about (a.k.a. wrong). Grin
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bassboy
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Re: Finally, some action...
Reply #32 - 06/14/06 at 21:44:21
 
If you check the white papers, the whole point of the DB is unconventional but very effective motor cooling, coupled with the unrivalled cone control provided by the sealed chamber.

If the motor is inside the sealed chamber you effectively reduce power handling by a huge amount by completely undermining the design that makes this box special and differentiates it from all the other fourth order bandpasses.  Instead of cooling the driver with airflow from outside, you let the voice coil bake in a sealed oven, heated by itself.  Of course this makes much more difference at higher power levels.
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60ndown
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Re: Finally, some action...
Reply #33 - 06/15/06 at 01:15:52
 
[quote author=bassboy  link=1147870641/30#32 date=1150317861]
If the motor is inside the sealed chamber you effectively reduce power handling by a huge amount . [/quote]

hhmmm?? im no scientist, but if the driver is rated @ 150 wrms, why would installing it into a sealed box 'reduce' its power handling?
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bassboy
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Re: Finally, some action...
Reply #34 - 06/15/06 at 01:44:57
 
The whole point is that you can feed it significantly more than the rated 150 watts because the voice coil won't melt because it is air cooled if the voice coil is NOT in the sealed chamber.

Put the voice coil in the sealed chamber and get your 150 watts or put the voice coil in the pathway of the outside air and get a lot more power handling and a lot closer to xmax and mechanical failure before the voice coil overheats and starts rubbing in the gap or completely fries and results in an open circuit.

Read the white paper and understand that the initial problem was overheating of the voice coil before the driver could reach it's mechanical limits.  With experimentation, the Decware design eliminated this problem and now the limiting factor in any given DB/driver combination is probably going to be xmax, which is still hard to push past the point of failure because of the resistive pressure of the sealed chamber.

This information is only what I have read, I don't have the plans and I don't have a deathbox.  Personally I have no interest whatsoever in increasing power handling, my audio philosophy makes me much more likely to try to increase sensitivity in a design like the WO or Imperial.
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Lee in Arkansas
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Re: Finally, some action...
Reply #35 - 06/15/06 at 01:48:22
 
hehe, get me some plexi and i'll video tape it.....I'll pop a 12, for poops and giggles.
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J_Rock
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Re: Finally, some action...
Reply #36 - 06/15/06 at 01:50:00
 
Bassboy is exactly right.  The whole point of the DB is to increase a drivers ability beyond its rating.  By doing this it just happens that the driver sounds better within its normal range.

Also, the air does not need to be moved or "cupped" whatsoever for the sub to work.  The air doesn't actually move.  The molecules in the air vibrate back and forth.

Thats why a flat baffle will work just as well as a cone.  It just happens its alot easier to make a stiff cone than a stiff square.

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bassboy
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Re: Finally, some action...
Reply #37 - 06/15/06 at 02:06:59
 
Lee, I thought you were going to try Bob's idea of splashing water with an old 12.  Maybe you can do that AND fry it in a DB at the same time.  Maybe if you are lucky, the water will short the coil and you can fry the amp too.  Maybe if you get REALLY lucky the whole car will burn.

Now THAT would be a video...diy demolition, lol.
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Lee in Arkansas
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Re: Finally, some action...
Reply #38 - 06/15/06 at 03:09:42
 
lol....I'm not plugging the water-12 into an amp.....it's gettin straight voltage.....it's gonna go BOOM.

I've got some old Road Gear 12's from Wal-Mart that just sit around and sound horrible.
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J_Rock
Ex Member



Re: Finally, some action...
Reply #39 - 06/15/06 at 03:18:07
 
I have seen a few 4 ohm subs that will handle a wall outlet for awhile.  They get roughly 3600 wrms for a short period of time.
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bassboy
Ex Member



Re: Finally, some action...
Reply #40 - 06/15/06 at 03:20:21
 
How about using a step up transformer to give it some REAL voltage?  Just make sure the polarity makes it go up, not down.  That would be a huge disappointment.  Cash prize if you can launch the cone free and clear of the basket.
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J_Rock
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Re: Finally, some action...
Reply #41 - 06/15/06 at 03:28:36
 
I have never seen that, I suppose with an older weaker spider I could make it happen.  You would need some serious BL though to get that cone to launch with enough force to break the spider, and surround- after it left the VC gap.
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bassboy
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Re: Finally, some action...
Reply #42 - 06/15/06 at 03:31:38
 
Yeah, I don't think it's possible.  Especially if it's full of water, lol.
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60ndown
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Re: Finally, some action...
Reply #43 - 06/15/06 at 04:50:42
 
i just read the white papers on the db again and it seems to me like testing was done with the magnet in the sealed side of the box, even the pictures confirm it? the db duct design exerts even pressure on the cone, relieveing wobble and wiggle of the cone and therefore allowing greater power handling.
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bassboy
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Re: Finally, some action...
Reply #44 - 06/15/06 at 05:42:21
 
OK, you got me there, I read it again and it appears you are right.  As long as SOMEBODY is paying attention we'll all be alright in the end.  At least I got you to read the white papers.  Me too.  It's been a couple of years since I read it and even then I was only skimming.  I only remembered "hot spots" and "increased power handling".  There are pictures that prove you are right and none that back up my posts, so I guess I got it crossed somewhere.  Maybe it was because in the pictures of the insert insertion the insert looked like it was prepared for a driver to be mounted in the way I have described (routed for flush mounting).  According to the white papers, I got everything wrong, as it was mechanical failure that presented itself as the first problem.  If I were to make one I'd try it both ways just to be sure it's really best that way.
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Bob in St. Louis
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Re: Finally, some action...
Reply #45 - 06/15/06 at 12:00:51
 
I'ts cool to see your name written by someone, it means they remembered you, that you may have made an impression. But geez bassboy!  I'd hate to be remembered by "The Driver Destroyer" Cry  LOL

Hey Jet, just throw the damn thing in a bathtub full of water (just don't do the 120v thing  :-/)

Bob - thanks for remembering me - in St. Louis

....carry on fella's,... good discusion going.  ;D Wink
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Adrian D.
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Re: Finally, some action...
Reply #46 - 06/15/06 at 12:53:01
 
ok guys, let's set things straight with the inverted/normal mounting.
it matters in direct radiating designs (ie ported, sealed and back-loaded horns). but it doesn't matter in designs where the port is responsible for 100% of the total output.
J_rock explained it nice. the air molecules vibrate.
as far as i'm concerned, mounting inverted shouldn't apply a-simmetrical pressures on the cone, because the whole structure is simmetrical.
one thing that worries me is that the magnet is very close to panel f. i don't know if i should worry about that. the air can move under the magnet.
what worries me is air movement just under the cone. using a 2inch baffle and because the sound splinter has such a big spider, i can bearly squeeze my finger through the round cutout and the basket.
i think i should ask steve...i wonder if he will answer my pm...
how many of you in for "send steve a pm and settle the mounting problem" ?
J_rock, i want to ask :
since you mounted all of your subs in the db inverted, did any fail (mechanically)? did you push them beyond their thermal limits ?
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Lee in Arkansas
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Re: Finally, some action...
Reply #47 - 06/15/06 at 12:58:42
 
Adrian, my first thought would be to cut the lower baffle slightly larger, but ask Steve.

My DB's are put off, yet again, due to my car blowing it's water pump. 2 nights a 6-pack of Fat Tire, and it's still not fixed.
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60ndown
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Re: Finally, some action...
Reply #48 - 06/15/06 at 13:18:45
 
all my dbs had the magnets in the sealed end, all of them were able too handle lots of power and sound great. i think the thermal thing is an issue if your going to play test tones or really heavy bass for long durations (1/2 hour straight or more) but for me most of my listening is @ moderate volumes with strong bass and occasional 'cranking'.adrian reverse your sub in a few weeks and let us know if it sounds different? i think the magnet being very close to panel f might cause noise (air rushing past) @ high volumes?
and molecules vibrateing? pfffft! im gonna stick with my subs fireing forward untill steve d tells me it makes no difference.
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Adrian D.
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Re: Finally, some action...
Reply #49 - 06/15/06 at 13:24:55
 
pm sent to steve. now just pray that he answers.
since it's raining outside i may just put the magnet in the sealed chamber today.
my guess is that it won't play as low as now if i keep the insert as it is now.
i'll remove the bottom lid to see how the air moves past the magnet.
60, isobaric mounting poses the same problem because one of the subs has the magnet in the vented part.
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Lee in Arkansas
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Re: Finally, some action...
Reply #50 - 06/15/06 at 13:53:38
 
find out your subs vas (is that the right one?) and move your baffle accordingly to make up that difference.
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Adrian D.
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Re: Finally, some action...
Reply #51 - 06/15/06 at 13:55:39
 
some estimates as to what effect the mounting has: since the sub displaces rougly 0.09 cf, it would be similar to moving the insert lower by 1 inch. covering the port changes the whole deal.
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Lee in Arkansas
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Re: Finally, some action...
Reply #52 - 06/15/06 at 14:27:31
 
So go like, 1/2?
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Adrian D.
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Re: Finally, some action...
Reply #53 - 06/15/06 at 14:53:10
 
i'm really undecided about reversing it. the magnet obstructs  air movement over panel f. that can't be good.
i just checked the mounting depth of J_rock's subs. it's identical to the mounting depth of mine. but J used a triple 3/4" baffle. so in his case it should be a 0.25" increase in the distance between panel f and the magnet.
???
EDIT :
good 'ole 25hz tone helps....
removed the bottom lid and i let the 25 hz tone rip. first with about 50w. i couldn't feel a diffrence in air movement between the part under the magnet and the 'unrestricted' part. i noticed now that the metal plate on the bottom of the magnet is conical. and it gets smaller at the edge. so, taking a better look, it seems like it's not that bad.
i increased the power until the insert vibrated too bad. only noise i could notice was coming from between the boxes. none coming from the driver and the pats that worried me.
waiting steve's answer, but my dad told me something really smart : "do you like how it sounds? yes? then leave it the way it is !"
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J_Rock
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Re: Finally, some action...
Reply #54 - 06/15/06 at 22:56:15
 
I place all my DB subs with the magnet structure in the ported enclosure.  Mainly because I have never had a problem with a mechanical failure in a sub driver.  Always the VC melting or something before the VC exits the gap.

I re-read the white papers also, and it is like 40 and up says, the magnet is to be put in the sealed chamber.

Its interesting to note the original driver they used is a Kicker Competition C-10 by stillwater designs.  I happen to have 2 of these in the 12 inch version.  And they are the only drivers I have tested in a DB and the recommended sealed and ported enclosures.  And the DB did outperform just like the article stated.

I have tried other 10" subs in their recommended enclosure against the DB, and the DB always wins.  

2 more things to edit in:

1.  The pictures of the insert on the website and in the plans do show the driver's magnet inside the ported section of the Box.

2.  Perhaps I have not had any trouble with mechanical failure because todays drivers are much more rebust than those of yester-year.  I mean, perhaps mechanical limits were indeed the limits back then, whereas thermal power handling is the main limit nowadays.
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bassboy
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Re: Finally, some action...
Reply #55 - 06/16/06 at 00:00:37
 
Like I said, I don't have the plans, but I swear I thought I saw a picture somewhere with the VC in the ported side.  I was wondering how I could have got so confused...

But like I also said, I spent a lot more time looking at the WO than I ever did the DB.
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Adrian D.
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Re: Finally, some action...
Reply #56 - 06/20/06 at 18:27:53
 
Steve's answer :
Quote:
I would try it as is first, then flip it around and see if there is a significant improvement.  If there is, then cut the second baffle larger so it can breath a bit more.

Steve

i guess it didn't clarify the magnet in sealed vs magnet in vented discussion Sad but it gave me some piece of mind.
btw, the insert still isn't bolted in and sealed but i like it the way it is now. with the insert just at the top of the port.
the thing with the mechanical limits was that the vcs were rubbing against the t-pole because of uneven pressures in the box. but there is a possibility that the subs bottomed out...
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J_Rock
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Re: Finally, some action...
Reply #57 - 06/21/06 at 03:53:01
 
[quote author=Adrian D.  link=1147870641/45#56 date=1150824473] i like it the way it is now. with the insert just at the top of the port.. [/quote]

This is the same spot both of my DB's were sounding best with the Infinitys.
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Adrian D.
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Re: Finally, some action...
Reply #58 - 06/21/06 at 05:49:18
 
kinda weird. i said i was going to spend a lot of time tuning but i tried only 2 positions.  :-/
i just need to borow a digital cam to take some pics.
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Adrian D.
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Re: Finally, some action...
Reply #59 - 07/28/06 at 19:20:54
 
seems like there is a chance the 'monster' will get covered in leather. i found out i have a neighbour that makes leather belts and jackets. so i hope he'll be able to help me.
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Adrian D.
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Re: Finally, some action...
Reply #60 - 09/30/06 at 08:49:08
 
leather work is done. everything is in place. only one dillema : should i stretch the leather inside the port, or should i leave the routed port uncovered and paint it black ?
i also plan painting all the mdf that is visible through the port.
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gexter
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Re: Finally, some action...
Reply #61 - 09/30/06 at 16:02:41
 
stretch the leather inside and then staple it as well as glue it. stretch it around our rounded port and then trim it and that will depend on where where you place the insert. If the insert is placed higher you could stretch the leather inside the port.
or at least on the rim.
but you may have to tack it on the inside of the rim of the port with tacks so when it tightens it will not pull away from the port.
I don't know how that would work at the port after time though.
I have done some Upholstery in the past but never fastened anything like that.
The sub itself would hold the Upholstery and the port was a plastic insert. most of all my stuff was ported with a round port insert.
Man!  lately this stuff is bringing back memories I remember covering a 6th order that I didn't even know was a 6th order about thiry years ago.
Sob* Im old  :( I never bothered with audio for nearly 20 year until the last few)
blah blah blah blah
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Adrian D.
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Re: Finally, some action...
Reply #62 - 09/30/06 at 20:24:37
 
i covered half the port. i mean you can't see bare mdf on the port, but the leather isn't stretched inside. box is also tuned and the insert sealed in place using strips of leather. no more silicone this time.
it turned out real nice. something is holding me back from trying it (currently using the sub in a crappy out of spec sealed box, but still sounding good), but considering i haven't listened to it in 2 months, it's weird.
i feel weird. must be the contact cement i'm using...homeless drug-heads use it as a cheap drug.
next piece of bare mdf that i'm going to cover is the amp rack  :-*
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Adrian D.
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Re: Finally, some action...
Reply #63 - 12/29/06 at 12:39:10
 
the 'beast'

the amp, x-over and amp rack

the finished monster db-10

pic of the guts and the way i sealed the insert

yeah, i'm not going to use gobs of power. but it's hardcore


soon to come...pics of the wo, the 'beast' in action and some comparison pics.
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Bob in St. Louis
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Re: Finally, some action...
Reply #64 - 12/29/06 at 14:00:43
 
Nice job Adrian!
I might be "anal retentive", but a fellow might solder the crimp connectors (eyelets) just in case the vibrations loosen the crimp.

Very good lookin' amp and rack you got there.  ;D

Bob
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Adrian D.
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Re: Finally, some action...
Reply #65 - 12/29/06 at 15:02:40
 
thanks.
2" mdf baffle. 1" mdf walls. i hope it won't vibrate. but if it does, the bottom panel is removable Smiley
still thinking about what to add below the x-over in the rack. something just for decorative purposes.


current sub setup :

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Bob in St. Louis
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Re: Finally, some action...
Reply #66 - 12/29/06 at 17:29:32
 
[quote author=Adrian D.  link=1147870641/60#65 date=1167404560]still thinking about what to add below the x-over in the rack. something just for decorative purposes. [/quote]

Not real decorative, but how about a cooling fan?
Maybe with a nice decorative wooden grill for the air intake to match your floors? ???

Bob
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Adrian D.
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Re: Finally, some action...
Reply #67 - 12/29/06 at 18:20:13
 
it would only cool the asorted crap in the storage space Sad
but it would look nice to have a wooden grill. just need to find the stuff we used to stain the wood, because there are plenty of leftovers wood pieces in the attic.
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