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pettaw · Jun 28th, 2002, 11:24

Just my two pennurth, and perhaps a stupid question, but are you sure that your sub is in phase with your mains, and are the mains in phase with each other, ie are the fronts in phase with the rears etc. If they're not, you'll get a weak lumpy bass and you'll be cranking up the bass to try and compensate. Check by throwing your sub in and out and checking if the bass feels 'tighter' with the sub in or not, if it feels tighter with the sub out than in then the sub is out of phase, rectify by swapping round + and - line level inputs for the sub, or perhaps you have a phase control on the head unit.

This is where James and I start to disagree. I don't like Low pass filters. I believe that you should run full range to your speakers and then simply supplement the depth and extension of the bass with the sub. 200W should be plenty of power, even if it is peak, I think that works out at about 75-100W RMS so thats loads of power. You are right, I believe, in that you may well lose the upper parts of the bass that the sub may not handle well.

I would set all of the EQ controls neutral first without the sub, then don't touch them again, and just adjust the power of the sub to extend the bass depth, setting the filter to roughly where you think the main speakers are starting to drop out.

If you do find that the mains can't handle the full range output, you will have to filter them with a low pass filter. The problem is that subs can quite often sound boomy because they put out too much upper bass and the way round this is to set your high pass filter low, to about 60 Hz. Of course this won't work if you want to run a sub-sat system, 'cos you'll be setting your crossover point from sub to sat at about 120 Hz and to do that the sub has to work well at those frequencies. A poor handling sub can't be cancelled out by any amount of EQ, in fact it'll just make matters worse.

IMHO a good sealed box seems to offer better sounds for the money, because the porting has to be done properly for it to work.

Hope that helps a bit. Different guys may have different opinions LOL

Andy

Jun 28th, 2002, 11:24	#25
pettaw Forum Support Team Last Online: Jul 23rd, 2023 15:29 Join Date: Jan 1970 Location: Glasgow, London	RE: A different kind of perfomance mod Just my two pennurth, and perhaps a stupid question, but are you sure that your sub is in phase with your mains, and are the mains in phase with each other, ie are the fronts in phase with the rears etc. If they're not, you'll get a weak lumpy bass and you'll be cranking up the bass to try and compensate. Check by throwing your sub in and out and checking if the bass feels 'tighter' with the sub in or not, if it feels tighter with the sub out than in then the sub is out of phase, rectify by swapping round + and - line level inputs for the sub, or perhaps you have a phase control on the head unit. This is where James and I start to disagree. I don't like Low pass filters. I believe that you should run full range to your speakers and then simply supplement the depth and extension of the bass with the sub. 200W should be plenty of power, even if it is peak, I think that works out at about 75-100W RMS so thats loads of power. You are right, I believe, in that you may well lose the upper parts of the bass that the sub may not handle well. I would set all of the EQ controls neutral first without the sub, then don't touch them again, and just adjust the power of the sub to extend the bass depth, setting the filter to roughly where you think the main speakers are starting to drop out. If you do find that the mains can't handle the full range output, you will have to filter them with a low pass filter. The problem is that subs can quite often sound boomy because they put out too much upper bass and the way round this is to set your high pass filter low, to about 60 Hz. Of course this won't work if you want to run a sub-sat system, 'cos you'll be setting your crossover point from sub to sat at about 120 Hz and to do that the sub has to work well at those frequencies. A poor handling sub can't be cancelled out by any amount of EQ, in fact it'll just make matters worse. IMHO a good sealed box seems to offer better sounds for the money, because the porting has to be done properly for it to work. Hope that helps a bit. Different guys may have different opinions LOL Andy