CSS SDX12 Build Thread

[GO-NAD!]

Both drivers were delivered by UPS yesterday. These are heavy suckers - approx. 45lbs/ea! And, they look almost too good to cover up in boxes. They include installation gaskets and fasteners. I'll warn you now - this build isn't going to go quickly. So, be prepared for an Alex-like pace of completion. Final modelling is not complete. Bob, at CSS, has enlisted people like Jeff Bagby and Nathan Funk to help come up with some numbers. If any of you are interested, the preliminary specs are listed on the CSS website.

These will be in separate ported enclosures, tuned in the 19Hz - 20Hz region.

I'm a bit torn as to how to power them. I like the power/cost aspect of the Behringer NU-000DSP series, but the convenience of going with a pair of SPA1000's is pretty enticing, as well. Decisions, decisions...

[lsiberian]

Do you have a woofer tester? If so you can determine the parameters yourself.

The preliminary parameters indicate a 27 liter box(13 3/8" cube) It looks like an excellent sub for small sealed operation

[GO-NAD!]

Do you have a woofer tester? If so you can determine the parameters yourself.

The preliminary parameters indicate a 27 liter box(13 3/8" cube) It looks like an excellent sub for small sealed operation

No, I don't have a woofer tester. I have no plans to build more after this, so I don't know that it's worth the investment. Yes, it looks like it would do well in a sealed box. But, I want extension and I'd prefer not to get into EQ-ing it for extension. So, I'd rather go the ported route. If you feel like doing a ported model, I wouldn't object. It seems that when I enter parameters in to WinISD, I get different results than everyone else. So, I don't trust my own modelling.

[lsiberian]

No, I don't have a woofer tester. I have no plans to build more after this, so I don't know that it's worth the investment. Yes, it looks like it would do well in a sealed box. But, I want extension and I'd prefer not to get into EQ-ing it for extension. So, I'd rather go the ported route. If you feel like doing a ported model, I wouldn't object. It seems that when I enter parameters in to WinISD, I get different results than everyone else. So, I don't trust my own modelling.

The draw back of porting a sub is you are going to have some level of port compression with nearly any design or you have a very large port.
46.42 with a 22.42 hz tune look optimal. You will need a high pass filter so factor that into your amp purchase.

I recommend the minidsp in a box. You get all the power of a DCX with a very small box at a reasonable cost. You could also get one of the DSP Behringer amps.

Though I strongly recommend getting a Peavey IPR or Yamaha P series for the quieter fans if fan noise bothers you.

[GO-NAD!]

The draw back of porting a sub is you are going to have some level of port compression with nearly any design or you have a very large port.
46.42 with a 22.42 hz tune look optimal. You will need a high pass filter so factor that into your amp purchase.

I recommend the minidsp in a box. You get all the power of a DCX with a very small box at a reasonable cost. You could also get one of the DSP Behringer amps.

Though I strongly recommend getting a Peavey IPR or Yamaha P series for the quieter fans if fan noise bothers you.

Yeah, I know this driver needs a longish port. I'm prepared for that. I'm still up in the air on whether to go with a Behringer or just going with SPA1000's. Thanks for the modelling.

[lsiberian]

From my calculator

46.42 liters vb
Dimensions
19in x14in x18in

Bracing(This is not significant on the Vb and will certainly vary.
1 x 4 in
33.5 in length

Port
1 x 4 in 38.25 in length
F3 28 hz

Many folks will give up headroom for more extension. I recommend going for headroom instead because most of your material is higher up and you get to play it louder.

You can obviously choose which path to take for yourself. If you want me to calculate a box size and cut out sheet for another vb and tuning let me know my program can do those things too.

[GO-NAD!]

From my calculator

46.42 liters vb
Dimensions
19in x14in x18in

Bracing(This is not significant on the Vb and will certainly vary.
1 x 4 in
33.5 in length

Port
1 x 4 in 38.25 in length
F3 28 hz

Many folks will give up headroom for more extension. I recommend going for headroom instead because most of your material is higher up and you get to play it louder.

You can obviously choose which path to take for yourself. If you want me to calculate a box size and cut out sheet for another vb and tuning let me know my program can do those things too.

I can go bigger than that. Even 85 litres isn't too big. I'd certainly prefer a tune in the 19Hz - 20Hz region. Am I correct in thinking that going larger can regain headroom lost to lower tuning?

[Swerd]

I've heard some bass cabinet designs done by Jeff Bagby (Salk SS 8, 10, and 12), and I think he has a good sense of how to tune a cabinet for the best bass response without overreaching.

I'd wait to see what ported cabinet design he comes up with.

[GO-NAD!]

I've heard some bass cabinet designs done by Jeff Bagby (Salk SS 8, 10, and 12), and I think he has a good sense of how to tune a cabinet for the best bass response without overreaching.

I'd wait to see what ported cabinet design he comes up with.

Oh, I'm not in a rush and I doubt that I'll be cutting any MDF this weekend. I'll wait to see what Jeff comes up with. In the meantime, I'm just curious as to what other guys come up with.

[lsiberian]

I can go bigger than that. Even 85 litres isn't too big. I'd certainly prefer a tune in the 19Hz - 20Hz region. Am I correct in thinking that going larger can regain headroom lost to lower tuning?

An EBS alignment is generally best at 1.6 to 1.8 times the optimal flat response. I can model it for you once I have the chance to add an EBS design to my software.

You'd generally tune to around Fs. I can run some models and come up with something later for you.