subwoofer?

[dietcookie]

Hi i'm using a pair of B&W speakers as my monitors and I want to get a subwoofer. Can I just go out and buy a subwooofer from anyone for example say a 10" subwoofer made from bose with a crossover and maybe a frequency selector and hook em up? would the subwoofer have to have a power supply? my monitors are passive so i'm using a power amp so the chain would be, power amp---->sub----->monitors

 

[masteringhouse]

Hi i'm using a pair of B&W speakers as my monitors and I want to get a subwoofer. Can I just go out and buy a subwooofer from anyone for example say a 10" subwoofer made from bose with a crossover and maybe a frequency selector and hook em up? would the subwoofer have to have a power supply? my monitors are passive so i'm using a power amp so the chain would be, power amp---->sub----->monitors

You will most likely want to buy a powered sub unless you want to get another amplifier dedicated to it. It will also have the crossover built in. In this case the chain would be line outs (L+R) into the sub, line outputs (from crossover in sub) to amp-> monitors.

 

[Han]

Be sure you get an active sub with an ajustable filter and gain control.

If the crossover is set too high, it may cause a bass bump which you won't like. The trick is to get only lows out of the sub that the B&W's don't produce.

 

[JuSumPilgrim]

Be sure you get an active sub with an ajustable filter and gain control.

If the crossover is set too high, it may cause a bass bump which you won't like. The trick is to get only lows out of the sub that the B&W's don't produce.

Actually, it really depends on whats going on with the bass response of your room to begin with. Assuming you didnt build it from the ground up to be a control room, you probably have varied peaks and dips from 30-200Hz. It may pay for you to cross over very high, say around 180Hz, and place the sub so you get an even distribution of bass at the mix position youll be better off than if you cross over low at say 60 or 80Hz. There are more places to place a sub than a speaker bec bass is mostly omnidirectional. Also the bass will sound more cohesive and focused as just about all the bass is coming from the same place i.e. the sub instead of the sub and speakers (which may have very dif bass sounds.)

 

[masteringhouse]

There are more places to place a sub than a speaker bec bass is mostly omnidirectional. Also the bass will sound more cohesive and focused as just about all the bass is coming from the same place i.e. the sub instead of the sub and speakers (which may have very dif bass sounds.)

Even though bass is mostly omnidirectional, the phase coherence between the sub and the speakers is also very critical. Some subs will also have a control which allows you to adjust this from 0-180 degrees and/or will have a polarity adjustments for this.

Essentially what you want to do is to feed a signal at the cutoff frequency, set the sub to be out of phase with the other speakers, and adjust the phase to the maximum amount of bass cut (then of course set the sub back in phase).