I'm looking to build a single chamber, sealed sub box for 2 JL Audio 10w6v3-D4 subs. However, the box is going in the back of a c6 corvette where I also need to store my top on occasion. So, the box must have a fixed width and height. The only variable is the depth.
If I use 3/4 mdf, the outside width is 28.5" and the outside height is 10.5", what's the best depth the box should be for an optimal tune? The last suggestion was 11". (How is the punch affected if that's either too deep or not deep enough?)
(Each sub is powered by its own JL Audio 500/1)
If I use 3/4 mdf, the outside width is 28.5" and the outside height is 10.5", what's the best depth the box should be for an optimal tune? The last suggestion was 11". (How is the punch affected if that's either too deep or not deep enough?)
(Each sub is powered by its own JL Audio 500/1)
In other words, if the box is less than 11" deep how is the sound affected? If its more than 11", what then?
For cars you have a lot of room gain. I would say at least 10 litres per driver. As big as you can live with would be better.
MDF is a bad speaker building material. It is even worse for subs. Good quality 15mm plywood will outperform three-forths MDF.
And if you…
Mount the drivers push-push — if you can still fit the box in your car — and you can dramaically reduce box vibrational load.
At bass frequencies the 11” should not be an issue.
dave
MDF is a bad speaker building material. It is even worse for subs. Good quality 15mm plywood will outperform three-forths MDF.
And if you…
Mount the drivers push-push — if you can still fit the box in your car — and you can dramaically reduce box vibrational load.
At bass frequencies the 11” should not be an issue.
dave
I read many years ago that mdf was the preferred material because of its denseness and less likely to resonate - BUT, I don't know. Why do you each have your specific opinion?
According to the manual for the woofer, you need 0.55ft^3 per woofer. The dimensions you have give you slightly more than that.
https://embed.widencdn.net/pdf/plus/jlaudio/rhrlgmknmi/10W6v3_MAN.pdf?u=ndijqi
https://embed.widencdn.net/pdf/plus/jlaudio/rhrlgmknmi/10W6v3_MAN.pdf?u=ndijqi
Density is not an asset unless it brings increased stiffness. And MDF is not resonance free, everything resonates. With a sub you want to push any potential resonances up as high in frequencies as you can so that they are never excited. Light & stiff is what you are aiming for — and well braced. If you could build the box of something like 4mm carbon fibre you would probably be better. Further MDF also tends to have low Q resonances which are easier to excite and more audible.
And push-push remobes some 90+% of the driver reactive energy flowing into the box. In a car, as small and light as you can get away with is good i’d think.
Matt is very wrong (in Post #4).
dave
And push-push remobes some 90+% of the driver reactive energy flowing into the box. In a car, as small and light as you can get away with is good i’d think.
Matt is very wrong (in Post #4).
dave
0.55ft3 = 16 litres per driver yields a Q = 0.8, which in a car with the big gain means exageratted bass. It falls within the greter than 10 litres.
Once you get to a certain size the actual volume of s sealed box becomes fairly non-critical (as long as it is not too big — for this woofer there is not too big. Volume stuffing will also give an apparent increase in the box volume.
dave
Once you get to a certain size the actual volume of s sealed box becomes fairly non-critical (as long as it is not too big — for this woofer there is not too big. Volume stuffing will also give an apparent increase in the box volume.
dave
It's not a bad speaker building material. Some of the best speakers available are made out of MDF. There are threads here about the pros and cons of different materials.