[PuZo]

I dont want to get into many details, but say I have a very small amp. I power a subwoofer to it, but it plays all the frequencies, ie its like a regular speaker. Is there something I can connect to it, like amp to *equalizer* to sub to make it only produce bass, not all the sound? Is this whole process not worth it? Will a sub last long if it plays all the frequencies? Im talking about 15wrms. Maybe something like a crossover? Thanks

 

[thebikingengineer]

Car stereos have bass blockers that you can put inline to cut out the bass frequencies for the treble and mid speakers. There may be something equivalent for home speakers but I haven't heard about it. Other than that, if you don't have a separate sub output then you'll get the whole signal through every speaker (including the sub). It shouldn't hurt the sub either way.

 

[PuZo]

Would it sound better? Its very small so it doesnt have to be fancy or anything, just block out the highs and mids

 

[UseName]

You can use a simple capacitor to act as a passive crossover for high frequencies, or a coil to act as one for low frequencies. Very cheap and effective.

EDIT For example:

You could add a 6.36 mHy coil in series on the + line to a 4Ohm speaker for a first order (6dB per Octave) 100Hz Crossover frequency.

Or if you want 2nd order (12dB per Octave):

you can add a 9.00 mHy coil in series on the + line and 281 µfd Capacitor in parallel behind the coil. This is also for a 100Hz Crossover.

You can also make a 3rd order one by adding an additional coil after the cap.

I realize this might be confusing.... but hope it helps. If you don't understand please ask, and post the impedance of the sub and I can tell you what type of cap/coil to try.

 

[brainsalad]

If your subwoofer is amplified, you need an active crossover in the audio line. Then you would just set the frequency and off you would go.

If your subwoofer is passive (fed off of the amplifier speaker terminals), you need to know the woofers impedance, typically 4 or 8 ohms and then using a couple of crossover component calculaters found all over the web, identify what coil and capacitors are needed for an 18db/octave crossover at 80-100 hz. Once you know those values, go to Parts express, buy them, solder them together on a board and it will go between the amp and speaker. This is known as a LOW PASS filter.

 

[brainsalad]

One of the tricks you can also do, is face the woofer into the floor and raised about 1-2 " from the floor. This will create an acoustical crossover, "muffling" the upper frequencies. Not very acurate and not as effective as my last post, but it's FREE and just might work "good enough" to avoid spending any money

 

[PuZo]

Quote:

Originally Posted by brainsalad /img/forum/go_quote.gif If your subwoofer is amplified, you need an active crossover in the audio line. Then you would just set the frequency and off you would go. If your subwoofer is passive (fed off of the amplifier speaker terminals), you need to know the woofers impedance, typically 4 or 8 ohms and then using a couple of crossover component calculaters found all over the web, identify what coil and capacitors are needed for an 18db/octave crossover at 80-100 hz. Once you know those values, go to Parts express, buy them, solder them together on a board and it will go between the amp and speaker. This is known as a LOW PASS filter.

This is all I know about the sub, its being powered by the amp, which is also powering 2 other satellites

Sub-woofer: 15 watts RMS (into 8 ohms, @ 100Hz, @ 10% THD)

 

[brainsalad]

Quote:

Originally Posted by PuZo /img/forum/go_quote.gif This is all I know about the sub, its being powered by the amp, which is also powering 2 other satellites Sub-woofer: 15 watts RMS (into 8 ohms, @ 100Hz, @ 10% THD)

I'm now confused. Is the amp built into the sub? or a stand alone amp?

 

[PuZo]

Quote:

Originally Posted by brainsalad /img/forum/go_quote.gif I'm now confused. Is the amp built into the sub? or a stand alone amp?

It a small 2 channel amp, basic basic amp, basically only gives power to whatever you plug in, it runs on ac and 8AA batteries. One channel I want to be for the sub, the other for 2 satellites. So I want the sub to only output the low frequencies. So the connection is sub, 2 banana cables into the amp, then to get sound, I plug a 3.5mm plug into the amp and into my ipod or whatever

 

[brainsalad]

I think your going to be better off getting a sat/sub system for a PC. By the time you pay for the parts for a crossover and deal with that, your going to be money ahead starting with something else.

 

[PuZo]

Its not for pc, its for portability, dont worry about money lol, but ya, what kind of crossover would I be looking at. I just want the low frequencies, thats it, but like you said, if the crossover is around 50+ dollars then I prob wont take it

 

[brainsalad]

Get one of these.

http://www.partsexpress.com/pe/showd...number=300-782

It's $32 and will give you a cross over and 25 watt amp for your woofer. You then would power your sats with your smaller amp.

 

[PuZo]

Quote:

Originally Posted by brainsalad /img/forum/go_quote.gif Get one of these. Parts Expressayton SA25 25W Subwoofer Amplifier It's $32 and will give you a cross over and 25 watt amp for your woofer. You then would power your sats with your smaller amp.

But its not battery powered

 

[UseName]

I recommend you try the Cap/Coil route first.

These components are dirt cheap from an electronics store. Maybe less than a dollar a piece. The added benefit is that you get to learn a bit about electronic filters.

 

[PuZo]

Quote:

Originally Posted by UseName /img/forum/go_quote.gif I recommend you try the Cap/Coil route first. These components are dirt cheap from an electronics store. Maybe less than a dollar a piece. The added benefit is that you get to learn a bit about electronic filters.

Can you show me a pic or where I could find one online?