i'm about to build my new sub box (AGAIN!!) and was toying with the idea of adding a perspex window behind each sub (subs will be facing forwards, perspex viewable from the boot) and was wondering how people trim their box with the windows? do you have to trim the vynil into the holes, then add the perspex after?

which would mean you'd have to start trimming the box before the front is glued and screwed down? it all seems too confusing!!

build the box except for the part you wish to be perspex. trim the box and the attach the persex last. screw in and wire you're subs.
problem solvered

I'm not really sure that would work, as the perspex pieces i want to use will probably be larger than the holes for the subs, making it difficult to fit after, and i'd rather the whole box be one nice smooth piece, rather than tacking on one side afterwards (not to mention its much easier to make sure its air tight when building it all at once...

heres a quick drawing of what i want, the squares would be the perspex windows, and the circles where the subs would be.

http://home.iprimus.com.au/dchamberlain/subbox.gif

cut the box and then use something to cut out a little bit and sit the perspex in there

Outside
====___ ____======
Inside



the ___ is where the perspex would sit on top, does this make any sence? lol

recess the panels for the perspex with a router and create a 'lip' (allowing for your material etc) then screw in you're perspex.
one you've don all your steps then just throw in your subs

hang on do you want the perspex on the inside?

either way you're gonna have to trim the panel or box before you place in the perspex

recess the panels for the perspex with a router and create a 'lip' (allowing for your material etc) then screw in you're perspex.
one you've don all your steps then just throw in your subs

thats what i was trying to say lol

you can buy persex backed boxes made by Q-MAX froma ny JB- HIFI
i know coz i got one :D

hang on do you want the perspex on the inside?

either way you're gonna have to trim the panel or box before you place in the perspex

yeah, i want it on the inside so u can't see any screws or glue etc, so looks like its going to be a tricky box to build!! by the sounds of it, i'll make the whole box except the front, trim the back (leaving the excess vynil uncut), fit perspex (the recessing sounds like a good idea aswell, should help with strength, even if it is on the inside) and then fit the front of the box, and trim the rest... all without getting the vynil dirty! who hoo!!!

what thickness of perspex should i use?

Use glass instead of perspex... Doesnt scratch.

Build your box, make the entire back out of glass. Glue it to the wood.

Then make a divider to make it all look pretty, and you can make the holes any shape u want.

perspex has more flex tim, When building mine, At High DB the glass Cracked so it was replaced with 10mm thick Perspex..

The Way I built mine was to Construct the Enclosure with Divider in the Middle, I used 25 mm Thick MDF for Solid Construction so when I had to Do the Perspex back wall I could Rout out the Recess necessary to make the Perspex internally Flat. I covered the Inside of the Divider with Carpet so it Pushed up against the perspex sealling the Two Chambers.

As for Hiding the Screws, I used a lot of 5mm Screws and Screwed it from the inside securing the Perspex to the inside lip of the back wall..

I used Carpet on the inside of the enclosure as it acts as dampening, making the enclosure sound sweet instead of a hollow Boomy noise, you may want to look into this..



Designing a Perspex backed enclosure is Hard and Expensive with alot of Carefull measuring and Trial and error..It is not the kind of enclosure you can complete in one day..
If you want to Install Neon to illuminate your subs , you have to make sure they are serviceable with out the Tube Actually being seenand making sure the wiring is air tight..

Make sure you design the enclosure so it will fit between the shock towers.. I made mine 5mm too wide and had to re-do the side walls so it would fit..


It cost me heaps to build mine but as you can see the results were worth it..

thanks for the advice guys, i'll have a look into carpeting the inside, i was just going to use the matt-black underbody/sound deadener spray, but carpet would probably look neater and give a nice contrast to the vynil outside.

i'll probably keep the centre divider hidden, and use a seperate piece of perspex behind each woofer, i think it would just look a little neater (and more room for error!) not sure about shape yet, i was thinking plain rectangle/square might look a little... well, plain! but shapes can go very wrong, and i'd rather keep it as simple as possible, so still got some thinking there!

Magnat, how have u hidden your wiring? i was thinking about using the terminals u can get from autobarn/tonkins etc, but i've heard that these arent that great? i've used them before in all my other boxes, and havent had any real problems (except when i used a square one and didn't quite cut the hole square!!) but apparently a lot of people stick to an air tight hole for the wiring? i have a hole saw, so neatness is not a problem, neither is air tightness.

Flex is exactly what you don't want in a box.
edit: more piccies
http://img163.imageshack.us/img163/7655/bootgroundpoint0vq.th.jpg (http://img163.imageshack.us/my.php?image=bootgroundpoint0vq.jpg)http://img307.imageshack.us/img307/3756/bootnodivider8zc.th.jpg (http://img307.imageshack.us/my.php?image=bootnodivider8zc.jpg)http://img307.imageshack.us/img307/7492/bootinstallwdeadener1wp.th.jpg (http://img307.imageshack.us/my.php?image=bootinstallwdeadener1wp.jpg)http://img307.imageshack.us/img307/530/ddthroughskiport12ff.th.jpg (http://img307.imageshack.us/my.php?image=ddthroughskiport12ff.jpg)

http://img307.imageshack.us/img307/6407/ddthruskiport40sd.th.jpg (http://img307.imageshack.us/my.php?image=ddthruskiport40sd.jpg)http://img244.imageshack.us/img244/5431/dividerfront9dk.th.jpg (http://img244.imageshack.us/my.php?image=dividerfront9dk.jpg)http://img244.imageshack.us/img244/2579/dividerrear2fx.th.jpg (http://img244.imageshack.us/my.php?image=dividerrear2fx.jpg)http://img244.imageshack.us/img244/3867/dynmd1003ea.th.jpg (http://img244.imageshack.us/my.php?image=dynmd1003ea.jpg)
http://img244.imageshack.us/img244/7533/enginebay2vp.th.jpg (http://img244.imageshack.us/my.php?image=enginebay2vp.jpg)http://img244.imageshack.us/img244/2508/lhstrimdeadened1kc.th.jpg (http://img244.imageshack.us/my.php?image=lhstrimdeadened1kc.jpg)http://img244.imageshack.us/img244/9490/lhsspeakerscentreconsole8ok.th.jpg (http://img244.imageshack.us/my.php?image=lhsspeakerscentreconsole8ok.jpg)

Check out glass... Its cheaper, stronger and scratch resistant. At the expense of being a tad heavier, but meh, if you have an install im sure thats the least of ur worries.

Peace

Tim

The Wiring to the Subs was made by Drilling Holes in the Bottom of the enclosure and Wires fed straight to the Subs on both sides. Blu Tac is used to keep the Enclosure Air tight and allows easy removal. The Neon Tubes are 8 inch and Secured at the front Directly above the Woofers with all the wiring Exiting on one side, the Wiring goes through the Divider high up and so all is hidden..Once again wiring is sealed in to keep both enclosures air tight and also for easy servicing.

Tim , What Db has that Bad boy acheived, Mine got to 132db then the glass Cracked.. With the Perspex we have managed 141.2db.
(Linear X used for Db Testing with Mic on the Front Seat 55Hz Sine using a Borrowed Set of Orion 2100 HCCA Amps)

Never had it metered, the glass wont be cracking too soon though. It's damn thick...

Makes a nice clunk when u tap it.

There's also two small ccfl's in there

oh dear dear magnat

yeah u could use a wopping thick piece of perspex like that, or u could use a thinner piece of glass. It might be heavier, harder to work with, won't ever scratch, but it won't flex at all.

Id like to see ur magnat subs try and break a 10mm thick piece of glass. Better yet, get a piece of laminated glass if you're really really worried.


glass > perspex...end of discussion :gtfo: :badgrin:

Resonant Frequency EEK.. Glass will more then likely shatter more easily then Perspex, hence the reason why I used Perspex..

This is the way I'd do it, build all the panels for the subwoofer box...but dont put it together...

With the back panels (the one with perspex windows)..rule the size of the perspex windows up minus 8mm...get a router to create the lip..put the perspex in with glue or something..

after that, vinyl it up, chuck the subs in, hook them up... :-)

Subs cracking the glass seems VERY hard to believe...

There are ppl out there with heaps more powerful systems and they have 10mm pieces of glass, without a problem....people like DD Phil have been building audio systems for like, 10 years using glass, with no problems!

Anyhooos billy, follow timmeh's idea. It saves u messing with two seperate pieces of glass, trying to fix them on. You probably wouldn't want to use screws on glass, because you'd need drill holes, and i was quoted $8 a hole....so i used silicon. Glue it on, leave ur sub(or something heavy) on the panel overnight....it'll never come off :badgrin:

Glass isn't terribly expensive either. Hell of a lot cheaper than perspex. Ring up ur local glazier for some info. To get a piece of perspex to be as strong as say, 10mm glass, you'd be looking at nearly 1" thick..

Not to mention I found Laser etching to be more easier to do on perspex then glass..

Yep glass wont shatter. There isnt that much pressure build up from bass anyway. Not enough to shatter glass under 3kw of power.

Glaziers will cut it all to size as well.

You probably wouldn't want to use screws on glass, because you'd need drill holes, and i was quoted $8 a hole....so i used silicon. Glue it on, leave ur sub(or something heavy) on the panel overnight....it'll never come off :badgrin:


:shock:

wouldn't it eventually rattle? i mean, i like the idea (makes my job easier) i'll still recess it into the panel, so it'll have 2 edges to stick to, i normally would use liquid nails or something like that... i just thought not having screws in it would mean over time it could break the seal?