Plywood

[winkychevelle 10+ year member]

OK, OK, OK. Yes, they can play down that low but remember SPL is logarithmic. If my 18 is doing 120db at 20hz and your pair of 6.5's are doing 100, there is literally 12x more energy in that panel.

My 7" drivers are crossed down at 60 and my sub plays everything below. But I can full range them without any real issues.

When you are talking about enclosures and stiffness, its relatively simple physics. The panels need to have enough stiffness to resist the increase/decrease in pressure inside the box as well as resist the forces of the cone/coil moving. My coil windings alone almost definitely weigh more than your entire moving mass combined.

Matt

Ps, yes a box determines frequency response and bandwidth. But you can only move so much air with 6.5" of piston area.

I dont disagree with anything you said here

 

[mat3833 10+ year member]

I dont disagree with anything you said here

Sometimes I forget that everyone has their own way of thinking. To me saying that my sub can play down to 20hz means it does it with authority. I haven't metered, but one day I will and I'm going to sweep from 60hz down to 1hz just so I have numbers to compare too.

Matt

 

[winkychevelle 10+ year member]

Sometimes I forget that everyone has their own way of thinking. To me saying that my sub can play down to 20hz means it does it with authority. I haven't metered, but one day I will and I'm going to sweep from 60hz down to 1hz just so I have numbers to compare too.

Matt

Yea 28hz is the lower limit of what I shoot for because you stop hearing the sound below that and more just feel it. It also starts to tear things up as you get lower. My pair of sa10v2 would play 25hz quite well but it was more flexing the truck and I would hear the panel flex(roof) more than the bass. And of course as I raise the frequency the ear starts to hear sound and the panel flex gets less severe.

This new 6th order I've designed is designed to be within 3db from 30hz to 65hz and cabin gain will allow it to go lower. I need to re measure cabin gain and do some deadening before finalizing and building that 6th order design. My mids while I'm happy with the silverflutes I'm considering trying to mount a 3.5inch mid in the kick or on the dash and run a larger 8inch midbass.

The jp77 amp just looks too good to not try a 3way setup though I hate the complexity in tuning I'm getting the bug to try 3way again