How many subs do you run?

[chucksrt]

I have a 15X20 room and attached are some pics of a set of infinite slope speakers I just finished restoring. The speakers are short and I was thinking about doing a DYI sub to put under the infinite slopes and raise them from the floor and remove the casters on the bottom of my speakers and make a dowl pin to connect the two enclosures or spikes, etc? would this be over kill? I want to do a infinity Kappa perfect 12VQ but I also don't know the proper way to amp them Plate or rack mount one amp for each or a single amp for both. I don't want to break the bank on an amp right now but will be willing to upgrade once I recover from the cost of doing the subs. Mainly used for HT but I also like to play my music when the wife and kids are out!!!

 

[ParadigmDawg]

Stereo subs would be great and a EP2500 would likely be able to run both subs. Andrew or Chris could give you the specifics as can a bunch of other guys on here.

 

[chucksrt]

the mains are so short, I would love to build something? I have a very nice pair of eclipse aluminum 88120.4 DVC 12" subs but if i remember right TLS Guy said that they might not be that great for HT so I'll just get the kappa perfect 12vq.

 

[fredk]

Thats the funny thing about small rooms. One sub will give you all the spl you could ever want, but small rooms benefit more from multiple subs to smooth out the bass response over a wider area.

I think that the ideal room has a minimum of two subs. From there, the sky's the limit. I have read about people building arrays with 20 small woofers in them and yesterday read about a system used in Germany/Europe that uses two sets of arrays with 4 subs each with the back array out of phase to cancel rear wall reflections.

Put in perspective, 2 subs is really quite conservative.

 

[adwilk]

Actually, the eclipse subs might work a little better in your case... they will allow you to make a smaller enclosure than the kappa will.. The ideal kappa box is enormous... I've had those eclipse subs in a car before and the high spl and low distortion is quite impressive. Then you're only out the cost of the cabinet materials and an EP2500. One amp will drive them just fine and you could always add another one later. You'll want a parametric EQ like the behringer DCX2496 or feedback destroyer pro...

 

[chucksrt]

how low can they be tuned? I know the kappa can be tuned down to 20hz, I would love to use the eclipse subs if the can come close. does anyone have any enclosure recommendations if they do seem to work (ported or sealed)

Actually, the eclipse subs might work a little better in your case... they will allow you to make a smaller enclosure than the kappa will.. The ideal kappa box is enormous... I've had those eclipse subs in a car before and the high spl and low distortion is quite impressive. Then you're only out the cost of the cabinet materials and an EP2500. One amp will drive them just fine and you could always add another one later. You'll want a parametric EQ like the behringer DCX2496 or feedback destroyer pro...

 

[WmAx]

You won't really get much size savings; if you tune the cabinet for the 10"s you have to say 25Hz, then the Kappa Perfect cabinet is also about the same size I expect. However, if you want smaller cabinets, you can go sealed, or move to drivers that work in tiny ported systems yet have massive output. But it takes very special drivers in sealed to get any considerable output around 20-25Hz, especially in the 10-12" diameter range. The Eclipse SW8200 in 3 cubic feet sealed can produce F3 somewhere around 23-24Hz in 3 cubic feet, and have some substantial SPL (though not as much as the Kappa Perfect slot port cabinet... ), due to it's unusual linear excursion abilities. A pair of the SW8200 would easily do what you want. You will need a parametric EQ available, as the SW8200 will have a high system qtc in that volume; the EQ cancels the peak, giving you a perfect smooth response.

-Chris

 

[chucksrt]

So 3 cu. ft. sealed is the way to go for each eclipse? does the shape of the enclosure have any bearing on the performance? If they are a perfect cube i'm guessing it will be pretty huge, also what do you recommend as far as where it should fire? Should it fire front, rear or down fire?

 

[chucksrt]

Actually it looks like it ends up being a 17" cube, that's not bad at all. Should I down fire it or just fire it forward?
Thanks,
Chuck

 

[WmAx]

3 cubic foot (net internal) is acceptable. It can be down or forward firing. The more volume you provide, the deeper it will play. 3 cubic feet will allow a practical -3 point of 24-25 Hz, and -6 point of 19-20Hz. These are free field numbers. In a 2000 cubic foot or smaller room, I expect -3 would be around 20-21Hz.

You must have parametric EQ band to use this subwoofer in order to effect a smooth flat response in this small volume. Using EQ to compensate for small enclosures in sealed applications is a common technique. This driver can take lots of power. 1000 Watts RMS will be no problem for this driver. Use a high quality amplifier; these drivers have been known to choke lower quality amplifiers. The O Audio amplifier will produce a real 430 watts, and has a subsonic filter and parametric EQ on it. It will work, but you will not come anywhere near using the driver near it's capabilities. The amplifier will clip far before that driver will begin to come near it's limits. In this way, you can be sure you will not be ale to over-drive the woofer, I suppose(looking for the silver lining.... ).

-Chris

 

[chucksrt]

Using the O Audio amps will allow me not to have to use the DCX2496 right? Is something like the DCX2496 only really needed when you run external amps to each speaker or set of speakers, like amp'ing the mains separate from the center and using another amp for the surrounds? just trying to figure out how it works?

 

[WmAx]

Using the O Audio amps will allow me not to have to use the DCX2496 right? Is something like the DCX2496 only really needed when you run external amps to each speaker or set of speakers, like amp'ing the mains separate from the center and using another amp for the surrounds? just trying to figure out how it works?

Because the O Audio 500W amps have parametric bands on them, you can get away without a DCX. But the DCX has far more function than simply applying a single correction band. The DCX allows for extensive response customization, room correction and for ideal xover/integration of your main speakers and subwoofers. That is, the DCX can do a lot more for you than simply get a smooth response from the subwoofers in this case.

-Chris

 

[chucksrt]

how would I use a DCX if I am using my receivers to power my mains and surrounds but am going to use a separate amp or amps for the subs? Am I only able to adjust and compensate for the subs? Should I invest in the DCX and look to turn my receiver into a pre amp and build my system into a multi external amp system? I love the sound of my receiver but I am sure the DCX could help but I also don't know if I can afford going to a multi amp system that sounds as clean without breaking the bank.

 

[WmAx]

how would I use a DCX if I am using my receivers to power my mains and surrounds but am going to use a separate amp or amps for the subs? Am I only able to adjust and compensate for the subs? Should I invest in the DCX and look to turn my receiver into a pre amp and build my system into a multi external amp system? I love the sound of my receiver but I am sure the DCX could help but I also don't know if I can afford going to a multi amp system that sounds as clean without breaking the bank.

At first, you can use the DCX to apply room correction for the sub and to shape the LF roll off to sound as 'tight' as you like. You can control subjective tightness of bass with the DCX's functions.

When you can, add external amp for the mains and use the receiver as a pre-amp. You don't need to use the DCX for surrounds. The DCX has three inputs so you can use it for L, C and R, and set L and R to 'LARGE' so they get the entire frequency range. Use the DCX to route the proper frequencies. The DCX is a far superior xover to the one in any receiver, and it can provide far more options for optimal sound and integration. Today you can top notch transparent amplifiers for not too much money. For example, a Yamaha P2500S will put a solid 250 watts into 2 Ohms, both channels driven, 20Hz-20,000Hz, or 310 into 4 Ohms. It has no fan noise. It has a superb signal to noise ratio. It is a top quality device and will offer more solid amplification than your receiver can manage. Step up and get the P3500S and that's 350 x 2 into 8 Ohms. There is also a P5000S and P7000S. Pretty much any power scale you want is available. In fact, I would probably recommend the P5000S or P7000S if you go stereo/dual subwoofers unless you don't mind opening up a Behringer EP2500 and doing a fan swap to make it silent from the listening position. The stock fan in that unit is loud.

But, if you don't want to move up to this quality/level of hardware, the O Audio 500W amps will be 'okay' for the Eclipse subwoofers.

-Chris

 

[mike c]

For example, a Yamaha P2500S will put a solid 250 watts into 2 Ohms, both channels driven, 20Hz-20,000Hz, or 310 into 4 Ohms. -Chris

that's 250w to 8 ohms

 

[chucksrt]

would it be worth it to get the Dayton WT3 woofer tester to check that the specs. are right from the manufacture? Would an enclosure be better matched to the woofer if tested like this or would it be so little difference that it shouldn't matter either way?

 

[avaserfi]

would it be worth it to get the Dayton WT3 woofer tester to check that the specs. are right from the manufacture? Would an enclosure be better matched to the woofer if tested like this or would it be so little difference that it shouldn't matter either way?

This depends entirely on how far off the supplied parameters are from the actual ones. Personally, I test all drivers before construction to ensure my time, effort and money is not wasted and an optimal cabinet is made for each build.