The WAF-2

[ryanbouma]

More of the Denovo stuff I posted about earlier. Here is my second build using the Denovo DW-654S and DNA-150 compression driver. Woofer is the DS175. It's a 9 x 15" baffle.



Will post xo schematic soon.

Driver Measurements (I also did off axis but didn't screen capture them).

http://i874.photobucket.com/albums/a...4SandDS175.png

Cross over Schematic



Completed Measurements

On axis, 15, and 30 degrees



30, 45, and 60 degrees



Vertical above axis (5, 15, 30 degrees)



Vertical below axis (5, 15, 30 degrees)



This speaker finally came together when I went with a 90d phase cross over. Why I didn't think this sooner I don't know. This is a better idea for surround duty anyways, imo. I felt like it just clicked into place when I hooked up this cross over. Sounded so much better. It was like, "there it is, I've been trying to find this...". I can finally say these kill the WAF-1. Like, obliterate them. Only 3hrs of listening and it's obvious this is a big step up. If you can afford the extra $30 a channel, use these.

The lobe points down a bit, so if these are mounted high for surround duty, they're a good choice. Mind the ceiling reflection though. Will work happily as mains in a budget system. Very versatile I believe. Very nice looking with extremely high WAF.

[pierre666]

Hi,

Is the baffle made of Pine ?

And the sides of plywood ?


Pierre

[ryanbouma]

Yes. It's not a finished product. Merely a test cab. I have pine laying around for test baffles because it routs and cuts easily.

This was more of a design posting to show off the Denovo stuff. I've since called this the WAF-2.x and am now working on the WAF-2.y which I think will be better. Uses the EOS6 waveguide and measures a little better than the DW-654S used in this one.

[mike1001]

i dont understand why you have the lp filter at 1200 anf the hp filter at 7500?
it seems like a big gap to me. also are you using active EQ? it appears from your posted notes(to me) like you are using @6db of boost and cut.

[ryanbouma]

Hi Mike,

Thanks for your question and I'm glad you asked, because it can be confusing for someone who doesn't use active cross overs. I design and measured the passive filter. And I designed but haven't measure an active filter. A builder could use one or the other, but not both at the same time. So the choice is the users. Ultimately I imagine very few people would go active with these, but I put it there anyways since you could buy a minidsp for the price of most passive cross overs these days.

To answer your question about the gap, it comes down to the acoustic response of the drivers. The DS175 has a rising response with increasing frequency. The DW-654S has a rising response with decreasing frequency. So if you apply filters that have a gap like that, they come back to flat and cross right around 2khz. If I just applied LR4 filters at 2khz, the responses would be very bad.

I am using boosts and cuts on the extremes of +6 and -12db. A designer has to be careful using boost and know when it's ok to apply boost. Especially 6db of boost. This can cause clipping and major amp power consumption if done wrong. The reason I was able to apply 6db of boost to the tweeter at 13khz is because I had already cut the total tweeter level by 16db. Another reason is because up at 13khz, very little power is required, so no real fear of clipping. The 5db of boost on the woofer at 1900hz is a little riskier. But again, after the BW12db/oct filter kicks in, the attenuated level at 1900hz is well be 5db, so again, no fear of clipping.

Sort of technical, I hope that helps. Please, ask any questions about it and I'll try and help. I test my designs and include the testing for others to see, much more thoroughly than most designers. Not knocking other designers, but my designs might be a bit difficult to understand for someone who doesn't understand all the details. I aplogize for that, but it's for the good Feel free to ask about any of the results.