Options for subsonic filter

[trojantrow]

Hi. Building a ported sub using an alpine type R 15inch driver.

Im aware I need a subsonic filter. plan is to tune to 17hz and apply a subsonic filter around 16hz to limit excursion.

Problem is. I already have a pro amp. A qsc rmx1450. Ideal power. But not subsonic filter option.

My avr has very advanced room correction. (anthem arc) But I think I can only set the high pass as low as 20hz thus loosing anything below that.. If I set it to flat, (fine for sealed) then it will not apply a filter and the sub could over drive when lower than tuning frequency.

Does anyone have a solution for this?? Other than sell the qsc and get an I nuke dsp. Thanks

 

[joebuddyguy]

You could get a minidsp if you don't want to buy a new amp. It has very extensive dsp options and probably cheaper than selling your qsc amp and buying an inuke.

 

[dotneck335]

This will work nicely:
Project 99 - Subsonic Filter

 

[scottjoplin]

My avr has very advanced room correction. (anthem arc) But I think I can only set the high pass as low as 20hz thus loosing anything below that..

I doubt it's a brick wall filter, likely to be enough output below 20Hz

 

[trojantrow]

Hi. Thanks for the replys. Seriously considering the mindsp but I have a concern.

Does this accept the Rca analogue sub output and apply the required filter? Would this not have to convert the signal to digital to apply the filter.? Then back to analogue... Bearing in mind the room correction has already been done and this would be even more digital processing. (bad for sound)

I would be quite happy to let the avr filter below 20hz. But I know there is some content below that. E.g. War of the worlds.

Simulation shows if I apply a 16hz butterworth filter, I I would still have decent output at 10hz. Any higher and hardly any output at 10hz. Hence why I want some customization.

I could just build it sealed and forget it. Don't know I would be happy with the output. Best sub I have ever owned is a svs sb12+ 400w small sealed sub.

 

[scottjoplin]

I don't know what to say.....to me 10Hz IS subsonic

 

[trojantrow]

So the question is. Massive output to 18hz ported vs output down to 10hz sealed but not as much output at 18hz and above. I have no clue what I would like the best..
50/50 music movies

 

[scottjoplin]

Don't forget placement and room gain

 

[trojantrow]

Good point the sealed could tame peaks better and room gain could get me to where I want to be..

At the end of the day its a sealed 15inch sub with 22mm xmax with 800w. In a 4m x 5m room. It shouldn't be too bad.