"Crossover Design for New Project"

[GM]

I'll have both, please!

That's the beauty of DIY, it's like going to Burger King, you can have it your way! :lollipop:

GM

[SOOTSHE]

I believe it. Veneered MDF is better than most furniture grade plywood these days based on what's available around here. Still, comparing a folded horn with its much greater acoustic pressure is an 'apples/oranges' comparison to a reflex cab. In its horn gain pass-band, the LaScala is making about as much acoustic pressure as almost four 416 woofers in a sealed cab, so even if made out of the best 19 mm plywood, doubling up the panels on the last third of the horn is easier for most folks than adding the amount of bracing required to keep it from 'flapping in the breeze' like loose lips.

Is the section below it a 'djk' inspired reflex chamber?

GM

GM,
Thanks for explaining the differences in pressure between the horn loading (LS) & the reflex loading (19's). Most folks said adding the braces would cure the resonance problem, but I found that this was not the case. As soon as I added the extra layers the whole system came to life.....even at low volumes. And now what you are saying sort of makes sense to me as I had all sorts of resonance issues with the horn loading, but the 19's seem perfectly fine. When I look at them as they came from the factory, I wonder how that can be so, as they have no internal bracing at all. I've often wondered if I would hear an improvement if I were to add bracing considering the results I got with the LS.

The bottom reflex chamber is a "DJK" design & allows the response to extend to 30Hz....really adds some depth & solidity to the bottom end on these babies.

[Altec Best]

Does someone have a suggestion on a good program for drawing up Cabinets in a 3 dimensional view.My program seems to be crashing. Thanks !!

[Panomaniac]

Google Sketchup?

Google SketchUp

[Altec Best]

Thanks Pano !!

[SOOTSHE]

Does someone have a suggestion on a good program for drawing up Cabinets in a 3 dimensional view.My program seems to be crashing. Thanks !!

Or you could try Caligari true Space.....microsoft freeware.

[Earl K]

It looks like the limiting component ( for sensitivity ) in this overall design will be the inclusion of the T350 tweeter .

I'm thinking the target sensitivity will need to be @ 100 db / 1watt, which purposely tosses a few db or so, so as to help incorporate the EV tweeter .

It ( the EV tweet ) appears to have an efficiency in the neighbourhood of low 100s ( once EQed flat 10 - 15K) . It appears to be good up to 15K .

I've never seen a spec sheet for the T350 .

Here are 2 similar spec. sheets / the ST350 & the T35A which will help ballpark the performance of the elusive T350 .

T35A

ST350B

John, once you have your newly purchased test gear up & running , I recommend you spend some time testing these tweeters ( with different passive crossovers ) to see what they can really deliver in response .


<> cheers

[Altec Best]

It looks like the limiting component ( for sensitivity ) in this overall design will be the inclusion of the T350 tweeter .

I'm thinking the target sensitivity will need to be @ 100 db / 1watt, which purposely tosses a few db or so, so as to help incorporate the EV tweeter .

It ( the EV tweet ) appears to have an efficiency in the neighbourhood of low 100s ( once EQed flat 10 - 15K) . It appears to be good up to 15K .

I've never seen a spec sheet for the T350 .

Here are 2 similar spec. sheets / the ST350 & the T35A which will help ballpark the performance of the elusive T350 .

T35A

ST350B

John, once you have your newly purchased test gear up & running , I recommend you spend some time testing these tweeters ( with different passive crossovers ) to see what they can really deliver in response .


<> cheers

Hey Earl, I know I have been looking for a spec sheet to no avail.The only thing I could find on it is it's frequency response of 3500 Hz to 23 khz.My telescoping boom Mic stand,cables,WT3 with scale arrived yesterday but I'm still waiting on the Behringer Calibrated Mic Thank You for your input and suggestions.I was playing with them yesterday (T350's) and found one of the fiber washers under the binding post is missing on one the (pos +) post of one driver.So the center of the post goes too high up into the center of post and doesn't allow you to get a wire in the post.Luckily I have a bunch of those washers & posts.I will get this fixed up quickly.

Thank You Earl :thankU: for your Kind Input :2thumbsup: Best Wishes ~ John

[GM]

I've never seen a spec sheet for the T350 .

T350

60 dB EIA = ~109.22 dB/W/m

GM

[Altec Best]

Holy Smokes Earl you beat me to the Thank You very Quickly

Thanks GM that is very,very,efficient 109.22 dB, I figure the 288's to be around 105-106 dB a little mis-match will I be able to deal with that.Then I still have to figure the efficiency of the dual 416B's

Thanks Again GM for the spec sheet now to make a copy !! :2thumbsup: