Subsonic Filter

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=53152
Printed Date: May 15, 2025 at 3:12 PM

Topic: Subsonic Filter

Posted By: tenny
Subject: Subsonic Filter
Date Posted: April 03, 2005 at 6:11 PM

Hello gentleman!

Question about a subsonic filter. I get how it works, that it basically blocks out low frequencies.

I have a power acoustic LT720 running Phoenix gold tantrun 5.25" doors and boston acoustics FX series 6x9's in the rear.

the front speakers I have the cross over set to High pass filter

the rear speakers are set to full range, but what do I set the subsonic filter to? I've played wiht it and it does not seem to make any difference at all. is it disabled when the crossover isnt set to a low pass filter

and that brings me to my next question whats the difference between a subsonic filter and a lowpass filter.

Replies:

Posted By: tenny
Date Posted: April 03, 2005 at 6:13 PM

Amp Specs say:

Variable Low Pass 30Hz-500Hz

Variable Hi Pass 50Hz-500Hz

Variable 24 dB Bass Boost

Variable Subsonic Filter 60Hz-200Hz

For the front speakers I have it set to high pass filter at 500Hz, then for the rears I have it set to Full frequencies, but the low pass and subsonic filter do not seem to make any difference.

I take it the subsonic is only acticated in low pass mode? or am I just not hearing it right lol

Posted By: tenny
Date Posted: April 03, 2005 at 6:21 PM

Boston Acoustics FX9 3 way

Frequency Response (3dB in car)
40Hz-20kHz

so does that mean I would want to set the crossover to full and the subsonic filter to the minimum setting of 60? or is that setting only active in LPF mode?

Phoenix Gold Tantrum 5.25"
80hz - 20khz

So I should try and set the high pass filter right around the 80 mark??

Posted By: tenny
Date Posted: April 03, 2005 at 6:27 PM

sorry for all the Q's, but one more

what should bass boost be set at when using 6x9's? I have it set at about 1/2 right now so that I am getting bass to the rears and not the fronts. I think the crossover in my amp just sucks lol because even with a high pass filter set to 500, if I play with the factory headunit and turn the bass up I am getting a ton of bass out the front speakers.

Posted By: stevdart
Date Posted: April 05, 2005 at 10:54 AM

The subsonic range on that amp doesn't make any sense to me. But, just leave it off anyway because you haven't indicated that a sub is in use here. Try setting the rears at about 80 Hz highpass and the fronts at about 125 Hz highpass for a fuller reproduction of sound in the car. And leave bass boost off, too.

Posted By: tenny
Date Posted: April 05, 2005 at 5:21 PM

you cannot turn the subsonic range off, you can only do the adjustments that I listed, that's what is puzzling me :(

i'll set the 6x9 to high pass, wont that take all the bass away from them though?