8 replies to this topic

[jimmyc]

Just wondering does the box need any treatment like an air tight coating of some sort? Also, how do you make a baffle?

Thanks.

[boozydave]

what wood are you using?
mdf is porous, but air doesn't flow through it. you can coat it in PVA, but makes faff all difference.

silicone all the corners and put 45 degree corners inside the box, so you don't get 'dead spots' for airflow.

a baffle is the face of the box that the speaker is mounted on. so, depends on the subs. one 8 should be ok with 18mm mdf. but 4x 15's will need a double baffle (2x18mm) and bracing (m18 bar between faces or similar)

HTH

[jimmyc]

It's plygloss? It's like ply but with the top and bottom surface glossed.

Oh right? Sweet that saves me some time. What do you mean about deadspots?

I see - I'll be putting two 15's on the top plate and the thickness of my material is 1 inch, will that be sufficient?

Cheers

[dumdum]

what wood are you using?
mdf is porous, but air doesn't flow through it. you can coat it in PVA, but makes faff all difference.

silicone all the corners and put 45 degree corners inside the box, so you don't get 'dead spots' for airflow.

a baffle is the face of the box that the speaker is mounted on. so, depends on the subs. one 8 should be ok with 18mm mdf. but 4x 15's will need a double baffle (2x18mm) and bracing (m18 bar between faces or similar)

HTH

silicone shouldnt be used in a box really, far better to just pva the inside of the enclosure also no need to round the corners of an enclosure, it robs valuable space, if it makes an enclosure louder id out money on it being because the box was smaller or they stiffened up the sides of the enclosure

air doesnt flow in an enclosure, it resonates, a radiused port is a method of increasing the surface area of the end of a port, hence allowing more air to resonate the volume of air in the port, then the flare on the other end makes it act on more air your in, hence giving more pressure swing, hence volume

[jimmyc]

Would silicone be alright though? It's just i have some sealant at home but no PVA or anything like that, but i'd go out and get some if it is going to be a better seal?

[greeef]

if you cut straight and glue true, you dont need sealant.

[Jason_D]

silicone shouldnt be used in a box really, far better to just pva the inside of the enclosure also no need to round the corners of an enclosure, it robs valuable space, if it makes an enclosure louder id out money on it being because the box was smaller or they stiffened up the sides of the enclosure

air doesnt flow in an enclosure, it resonates, a radiused port is a method of increasing the surface area of the end of a port, hence allowing more air to resonate the volume of air in the port, then the flare on the other end makes it act on more air your in, hence giving more pressure swing, hence volume

if 45's getting the box louder is to do with making the box smaller, why doesn't the peak raise? and also, if air doesn't "flow" why does air move in and out of the port? and also, why does a smoother box get louder? if the air didn't flow then surely it wouldn't matter how rough the inside of your box is?

im just curious why you say it doesn't flow?

[Issac008]

45's and smoothing help out alot with making it sound better and you can gain slight increases in db. putting a finish on the inside would help but spot on with glue and having very straight cuts on your wood helps alot

[boozydave]

dumdum, i know you know more than me making boxes, but.....

how come the big boys use magic db dust to find 'dead spots'? if the dust doesn't move when subs are working, it's classed as a dead spot. if air doesn't move, how can this work?

why smooth the inside of boxes to help the 'air flow'?



glad jason is curious like me