CSS SDX12 Build Advise

[Spentitall]

I purchased two of these drivers when they were first released many years ago. Due to circumstances, they were installed into some custom boxes but never powered up. I've since moved and seem to be spending more time at home, so I thought I'd repurpose these drivers. I have a small house and will need to integrate the driver(s) into the entertainment stand due to space constraints. Looking for advice on two options. 1. Single driver in 2.1 ft3 enclosure with labyrinth style slot port 2.5" x 11" x 90" tuned to 20hz or 2. Dual drivers in sealed 1 cu/ft enclosures. Will be utilizing a Behringer NX3000D in either option (2x900W @ 4ohms or 1 x Lots at 4 ohms). Any other options I should concider?

For music (mosly vinyl) I currently use a Yamaha A-S501 to drive NS690II 3 Ways. Balance of HT speakers are Q Audio 3020's driven by STRD1080 in 5.1 configuration. Wouldn't mind loosing the 690II's and using the 3020's with new subs for music? Would free up lots of floor space. Then would be one system for 50/50 music and HT.

Thanks!

 

[lovinthehd]

Better for the diy subforum....did you check out the recent review here? https://www.audioholics.com/subwoofer-reviews/css-sdx12

 

[Spentitall]

Sorry, new here. I didn't realize there was a separate DIY sub forum. Ya, I read that review and know the drivers are decent. Just wondering if the effort to build a single ported is going to get me much further ahead than two sealed which are obviously much easier, taking into consideration the amp driving them.

Should I copy the original post into the DIY Sub forum?

 

[lovinthehd]

Sorry, new here. I didn't realize there was a separate DIY sub forum. Ya, I read that review and know the drivers are decent. Just wondering if the effort to build a single ported is going to get me much further ahead than two sealed which are obviously much easier, taking into consideration the amp driving them.

Should I copy the original post into the DIY Sub forum?

You can ask a mod to move it. Or leave it, not a huge deal (and don't recommend duplicate posts) but where building of subs is generally discussed. If you have two drivers and are worried about the build complexity, I'd go sealed (what I did when I started doing my own sub builds as a new woodworker). Certainly the review shows that they work well sealed

 

[Spentitall]

Thanks. The woodwork doesn't scare me as I have access to a shop. I guess it's more a question of the end result based on the two options and the power amp driving them. The single driver ported is obviously a more complicated build, the amp will more than suffice, the dual sealed is an easier build but will the amp be enough to drive them as the recent review said 1000W wasn't driving them to Xmax and suggested more headroom. If a single ported with lots of power will perform equally as a dual-sealed with 900W each, then I'd be happy to build the ported and give the second driver to my son to play with.

 

[lovinthehd]

By dual I assume you mean separate boxes, no reason really to put them in a single box for best use.

 

[Spentitall]

Yes, two seperate boxes as modelled on CSS site.

 

[lovinthehd]

With adequate eq and amp shouldn't be an issue....but different

 

[SoundUp]

A 90" long port will probably have to be bent several times to fit in your enclosure, leading to compression issues, which are already a problem with slot ports. Even if you could somehow do a straight shot 90", you'd still be looking at a port resonance at 75Hz, which is right in the driver's passband and would be audible as a sluggishness around that frequency. For these reasons alone, I'd avoid the ported option (which is why I think CSS only recommends using passive radiators with them), but when you add in the simplicity of the build and the fact that 2 subs sealed will have as much or more output capability as a single ported, I think the 2 sealed option wins in a landslide.

 

[Spentitall]

Thanks for your feedback as it confirms my thoughts. Yes, the only way to get a port that long is doing a labyrinth style, which is obviously more complicated and not convinced I'd get any benefit from the extra effort. I have decided to build two 14" square (1cu/ft) enclosures and see how they perform. As you mentioned, based on CSS curves, it looks like two sealed have the same output as one ported and should be much easier to tune with the NX3000D. Cheers!

 

[annunaki]

I would recommend using passive radiators with this driver over a vent if you wanted the output it offers over sealed. the vent just gets too long at the proper vent velocity (<=17m/s)

 

[Spentitall]

Unfortunately, due to space constraints, I am building the subs into an entertainment stand and won't have the exposed surface area to add passive radiators. Will try two sealed first and see if it satisfies my needs.