Okay, I just started looking into DIY audio equipment, and for right now I'm gonna try my hand at building some subwoofers.
I don't have my own system to run them on yet (just a cheap-o RCA bookshelf stereo), so I plan on testing my equip. on my neighbors set-up...
I've been making some plans to build a subwoofer tube enclosure that will house two 10" subs, in a 4th Order Bandpass set-up.
Each sub would have its own vented enclosure.
It would be like vented enclosure, sealed chamber (for both subs), then the other vented chamber
|------------|---------------|-------------|
|_____ | woofers | _____|
|__port | | port__|
|------------|---------------|-------------|
*i hope that turns out*
My question is... since I am going to have both subs running off the one enclosure, what effect would I get if i wired the subs opposite of each other...
i.e.
Amp "+" would goto "+" on the first sub and "-" on the second.
and the Amp "-" would goto "-" on the first sub and "+" on the second.
Lastly, with regards to the ports, so long as they are tuned correctly, does it matter if the ports face the subs directly? Or should they be angled or something?
I hope this didn't come across as a total newbi question and I hope someone can help me.
I don't have my own system to run them on yet (just a cheap-o RCA bookshelf stereo), so I plan on testing my equip. on my neighbors set-up...
I've been making some plans to build a subwoofer tube enclosure that will house two 10" subs, in a 4th Order Bandpass set-up.
Each sub would have its own vented enclosure.
It would be like vented enclosure, sealed chamber (for both subs), then the other vented chamber
|------------|---------------|-------------|
|_____ | woofers | _____|
|__port | | port__|
|------------|---------------|-------------|
*i hope that turns out*
My question is... since I am going to have both subs running off the one enclosure, what effect would I get if i wired the subs opposite of each other...
i.e.
Amp "+" would goto "+" on the first sub and "-" on the second.
and the Amp "-" would goto "-" on the first sub and "+" on the second.
Lastly, with regards to the ports, so long as they are tuned correctly, does it matter if the ports face the subs directly? Or should they be angled or something?
I hope this didn't come across as a total newbi question and I hope someone can help me.
Im not entirely sure what you are asking as the diagram you drew with characters, I find, difficult to understand. Anyway regarding the wiring of the subs to the amp. You dont want to sire the subs up one +- and the other -+, this will cause a cancellation effect and result in zero bass and much lower powerhandling.
On the other hand if one driver fires into the enclosure and the other out of it (mount one driver so you seen the cone from the outside of the cabinet and the other drivers the magnet) then you will want to wire them up as you described. This set up has many desireable attributes to it such as reducing drive nonlinearities and distortion.
Im not too clear on what you mean about the ports directions and im not very knowledgeable when it comes to bandpass designs. But in a normal vented enclosure you can mount the port anywhere you like as long as it has sufficient room to breathe. Ports are generally located on the backs of loudspeakers because the "chuffing" noise associated with high SPL and too small ports is reduced if its not facing you, also port termination can look hideous if not done right so having out-of-sight is also a bonus. Beware tho of small animals if you have a port located hear the floor small rodents could have a habit of climbing in and getting stuck, then would get a surprise when you Q the explosion scene in a bockbuster or something to impress someone
squeek!.
Anyway I hope someone else posts her because Im sure that other people will have better recommendations regarding bandpass then I do.
Matt
On the other hand if one driver fires into the enclosure and the other out of it (mount one driver so you seen the cone from the outside of the cabinet and the other drivers the magnet) then you will want to wire them up as you described. This set up has many desireable attributes to it such as reducing drive nonlinearities and distortion.
Im not too clear on what you mean about the ports directions and im not very knowledgeable when it comes to bandpass designs. But in a normal vented enclosure you can mount the port anywhere you like as long as it has sufficient room to breathe. Ports are generally located on the backs of loudspeakers because the "chuffing" noise associated with high SPL and too small ports is reduced if its not facing you, also port termination can look hideous if not done right so having out-of-sight is also a bonus. Beware tho of small animals if you have a port located hear the floor small rodents could have a habit of climbing in and getting stuck, then would get a surprise when you Q the explosion scene in a bockbuster or something to impress someone
squeek!. Anyway I hope someone else posts her because Im sure that other people will have better recommendations regarding bandpass then I do.
Matt
Bandpass subs=yuckiness.
Onto your wiring idea, This is parallel wiring which means that two 8ohm woofers become a total load of 4ohms. Now, since you have reversed the order on the second woofer, they are now wired in opposite phase.I wouldn't worry about cancellation (unless I see your diagram) but, usuallly BP boxes don't have the woofers physically aligned such that cancellation can occur.
Onto your wiring idea, This is parallel wiring which means that two 8ohm woofers become a total load of 4ohms. Now, since you have reversed the order on the second woofer, they are now wired in opposite phase.I wouldn't worry about cancellation (unless I see your diagram) but, usuallly BP boxes don't have the woofers physically aligned such that cancellation can occur.
no skill
sorry about the quality of the picture, but i cannot draw for nothin!
hand drawn
i hope this explains better my idea
sorry about the quality of the picture, but i cannot draw for nothin!
hand drawn
i hope this explains better my idea
i figure...
i figure that even though i'm running two subs off one enclosure, i'll only need the amount of space for one driver because they will be running opposite each other...
ya know
i figure that even though i'm running two subs off one enclosure, i'll only need the amount of space for one driver because they will be running opposite each other...
ya know
Because they are facing each other they are 180 degrees out of phase physically. Wiring them in 90 degree phase, electrically, would make them a total of 270 or 90 degrees out of phase (total). You would, I think, lose 3dB.
the level of technicality is rising...
i ordered some books like a week ago
(Designing, Building, and Testing Your Own Speaker System with Projects, and Loudspeaker Design Cookbook) So they should be here in like a week and a half.
hopefully they will be able to also assist me.
i ordered some books like a week ago
(Designing, Building, and Testing Your Own Speaker System with Projects, and Loudspeaker Design Cookbook) So they should be here in like a week and a half.
hopefully they will be able to also assist me.
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