LPF, HPF, Subsonic, Gain

[DGold]

On my amp it has a subsonic filter from 20-50. If this is on do i still need the low pass n high pass or does the subsonic do that for me? Also, my gain has no numbers on it jus min and max so the only way i can set it accurately is an oscilloscope right? I had someone else tune my amp because i then knew nothing, now the amp is running at a lower ohms so was wondering how much to adjust it, even though its powering my subs half of what their rated to handle anyway. Any input on this?

[spl4life]

kinda need more info... whats ur box tuned at? what subs and amps u using? whats the RMS rating for ur sub and amp?

i would say, as long as ur not clipping it.. you should be fine..

also if ur only puttin in half the RMS... u can turn up the gain... but like i said... jus make sure ur not clipping it...

[Neel]

Say your sub has no sub sonic filter or low pass, it would be receiving signals from 1hz - 20khz. Signals that are way to low for the sub to play making the sub bottom out (in certain situations,mainly if your getting loud and not too worried about those low notes needed in SQ applications) , and frequencies that are too high that also make it work harder then it should and also sound terrible. So the idea is, the subsonic filter will stop the lower frequencies from playing, on your amp you can change this anywhere from 20-50hz. The low pass is to keep all the higher frequencies out (in most cases people set them around 80hz) so the idea is the sub only plays frequencies from 80hz down to whatever you set your subsonic at (in your case anywhere from 20-50hz.

The gain should be set to match the maximum unclipped voltage output of your source and then left alone, you can then change the level of the sub using a bass knob or your source unit. The idea is that you dont want the amp to send out a clipped signal (looks like a sine wave with the tops and bottoms "clipped" off) to your speakers / subs. Set it once correctly , you can use a voltage meter instead of an oscilloscope if you dont have access to one, from my experience using the voltage chart and the oscilloscope are usually pretty similar in terms of voltage output before clipping.

[SQMonte]

So the idea is, the subsonic filter will stop the lower frequencies from playing, on your amp you can change this anywhere from 20-50hz. The low pass is to keep all the higher frequencies out (in most cases people set them around 80hz) so the idea is the sub only plays frequencies from 80hz down to whatever you set your subsonic at (in your case anywhere from 20-50hz.

The gain should be set to match the maximum unclipped voltage output of your source and then left alone, you can then change the level of the sub using a bass knob or your source unit. The idea is that you dont want the amp to send out a clipped signal (looks like a sine wave with the tops and bottoms "clipped" off) to your speakers / subs. Set it once correctly , you can use a voltage meter instead of an oscilloscope if you dont have access to one, from my experience using the voltage chart and the oscilloscope are usually pretty similar in terms of voltage output before clipping.

Well said, I agree 100%

[DGold]

So even running at lower ohms I do not have to adjust the gain for the new output? My subsonic is just an on/off switch. Its an Audiobahn. Im not happy with it currently but i bought it 3 years ago when i was 16 and didnt kno much. I have it hooked up to 2 Audiobahn subs rated at 400w RMS a piece so this sub is only givin half at the most.

Amp, Will be upgrading this soon

http://www.onlinecarstereo.com/CarAudio/Pr...ProductID=17047

Edited July 4, 2009 by DGold

[basshead4life]

So even running at lower ohms I do not have to adjust the gain for the new output? My subsonic is just an on/off switch. Its an Audiobahn. Im not happy with it currently but i bought it 3 years ago when i was 16 and didnt kno much. I have it hooked up to 2 Audiobahn subs rated at 400w RMS a piece so this sub is only givin half at the most.

Amp, Will be upgrading this soon

http://www.onlinecarstereo.com/CarAudio/Pr...ProductID=17047

thats not going to be an upgrade unless you get 2. because those amps are only 400 rms. and whats the ohms of the subs.

[xander87mp]

what's subwoofer have you??

[DGold]

Had to google to find it, I have 2 of these, Theres an amp thats the same style but puts out 400w rms x2 at 2 ohms. The subs i have were in parallel but I switched em to 1 sub per channel because i noticed a significant volt drop for almost any bass. I'm going to upgrade the entire system most likely not jus the amp. Audiobahn was a good first/cheap system 3 years ago but i think its time to move on once i get the money(college is expensive).

http://www.bizrate.com/carsubwoofers/audio...er--pid7579872/

Edited July 6, 2009 by DGold