DIY Sealed 15" or 18"??

[lsiberian]

Is that a brand?

It's a type like Peavey IPR or Behringer EP4000 or Crown etc.

 

[Jeff R.]

How about using the Stereo Integrity 18....it is about $50 cheaper and according to the DataBass review may be a more capable driver?? It definitely has more excursion...not sure about how much clarify you sacrifce though.....

 

[fuzz092888]

It's worth a try I think. The only issue I see is that you have to be careful about supplying too much power to it. I'd probably get the dual 4 VC, wire in series to get 8 ohms and get something like a crown XLS 1500 and use it to drive two of them in stereo mode. At 8 ohms the crown is pumping out 300 watts RMS which is well below the power rating of 600, but in this case that's a good thing, since as noted on data-bass the max power handling is rated by x-mech not thermal power handling. Try to go pushing 1000 watts through one of these things and the driver will go slamming into the back plate causing serious damage. While that can be true of any driver when the max power rating is exceeded, it can be especially worrying with subwoofers since people generally like to crank the volume when watching movies. Big explosions+too much power can get you in trouble real fast. I'm not entirely sure I like the power rating dictated by X-mech rather than thermal.

Something to keep in mind.

 

[t3steve]

Fuzz,
You might want to try modeling one before you recommend only 300 watts RMS

 

[lsiberian]

How about using the Stereo Integrity 18....it is about $50 cheaper and according to the DataBass review may be a more capable driver?? It definitely has more excursion...not sure about how much clarify you sacrifce though.....

Looks really good to me. I'm going to have to check out a ported option for that beast. 15fs is really low.

 

[fuzz092888]

Fuzz,
You might want to try modeling one before you recommend only 300 watts RMS

You may want to read what I posted and referenced first. The recommendation has to with not destroying the driver. A lot of you good modeling does if you don't understand the actual physical limitations of the driver in question. Just sayin'

 

[t3steve]

Using the recommended 600W in a large 10.3 ft^3 box the driver won't reach xmax untill all the way down to 10hz.
If you reduce the box to 6 ft^3 and eq flat you can use a 1000watt amp.
Or am I missing something?

 

[fuzz092888]

Using the recommended 600W in a large 10.3 ft^3 box the driver won't reach xmax untill all the way down to 10hz.
If you reduce the box to 6 ft^3 and eq flat you can use a 1000watt amp.
Or am I missing something?

Did you read the data-bass writeup I mentioned? Apparently not, since your question would have been answered.

At what looked like maybe 60 or 65mm peak to peak the driver abruptly tapped the back plate. Xmech effectively seems to be closer to 30 or 35mm inward. This was confirmed by pressing in on the cone to the point where the coil touches the back plate. the driver won't suffer any damage if this happens lightly a few times but you will want to be careful with the power. Indeed Stereo Integrity confirms that the power rating for this driver is based on the mechanical overload not what the coil will handle thermally. They recommend 600w and no more for this driver. The very compliant suspension results in little power being needed to move the driver to full stroke. SI's recommendations for this woofer make sense in light of this and the driver will not make much use of more than 5 or 600w of power without getting into trouble. Depending upon the particular enclosure design more power could possibly be used but careful measurement and simulation would be needed to assess the wisdom of applying more power.

Straight from the manufacturer, that using more than 600w should be done only with very careful modeling and simulation. Given that 600w is capable of pushing the driver to it's mechanical limit in many situations, personally I wouldn't want to get anywhere near that. Furthermore, we're talking about RMS here which is additionally why I would want less power going into the sub. Transient peaks can be up to including and possibly more than double the RMS rating. Ergo, a 300w crown XLS1500 should give the OP a relative amount of comfort when driving the sub hard and cranking the volume if he so wishes.

Perhaps I am missing something, but Ricci and stereo integrity seem to think 600w is about it.

 

[moves]

What's the difference between a passive and an active 18.0? Besides the 1k price difference? Is it worth the extra 1k?

 

[fuzz092888]

What's the difference between a passive and an active 18.0? Besides the 1k price difference? Is it worth the extra 1k?

Passive has no amp, active comes with the funk 2400w amp, which also has full DSP control. Personally I think the extra 1K is worth it, but I'd probably ask and see if I could get the sub as a passive with the separate version of the amp.

Whether or not the extra 1K is worth it is up to you. If you plan on implementing your own correction, then no it probably isn't, but if aren't going to be doing that stuff then I think it really is.

 

[t3steve]

According to Ricci on Databass:

"The testing was stopped at the 118 volt sweep due to driver distress noise, concerns of bottoming the driver and broad band compression of about 3dB setting in. "
assuming 4 Ohms thats 3400 Watts

 

[fuzz092888]

According to Ricci on Databass:

"The testing was stopped at the 118 volt sweep due to driver distress noise, concerns of bottoming the driver and broad band compression of about 3dB setting in. "
assuming 4 Ohms thats 3400 Watts

True, I was looking at the actual driver page, not of the in box testing page. However, this is only true for moderately sized sealed configuration as he also notes on the page you're referencing. The power concerns are still valid for larger sealed applications, vented or IB installations, which is also noted.

As you can see, given all the facts there are a few valid concerns about the driver in certain applications. I'm not saying it's a bad driver and would say that's it's excellent for the price. However, without careful planning and implementation, you shouldn't go pushing 1000+ watts through it due to its mechanical limitations and thermal power handling issues unless you've planned for this in the design.

 

[Jeff R.]

Has anybody had any exposure with the new Dayton Ultimax 15" driver?

 

[Ricci]

Mechanical power handling of drivers is very enclosure and frequency dependent. So while a small sealed box may prevent a dreaded clank with an input of 100volts a much larger bass reflex may only handle 50 volts. SI's recommendations for their woofers are based on large enclosures and or free air and are there to cover their butt from warranty claims if someone who has no clue what they are doing straps a 2kw amp to one and cranks it.