P.A. sub project

[juxta]

2 things to keep in mind.

1. These are 4 ohm drivers, not 8 ohm, so your amp needs to be 2 ohm stable, and needs to be rated at at least 700-1000 watts per channel at 2 ohm and have a 30hz high pass, if your crossover / dsp doesn't have it. (assuming you are planning on running a pair of subs in parallel to each sub amp channel.)
2. don't split your subs, unless they are at least 50' apart.

Also, no permission needed from me on the TH design -- it's fair game for anyone. I'm not one of those 'ownershippy' kind of guys.

Ok thanks
Is the EP2500 ok? Can get one for $720 down here compared to $1300 for the amp Cowan suggested.. As it'd be running only subs I'd prefer to spend more cash on lighting/beer etc if the difference is negligible.
Can get pretty much anything from local staging company free in the mean time, I've got a mate there, just prefer to use my own gear in case something goes wrong..
Doesn't look like the EP2500 has a filter...

Is this the final stat:

Quote from don:

Here's my version of Jim's Tapped Horn. I ran this by Jim, and he suggested that I share it with the forum. This thing is BIG, over 600 liters, but that's not a problem for a fixed install.

The average guy should be able to get all of the saw-work done at a decent lumber yard, and complete it in an afternoon. If all the 24" cuts are actually 23 3/4", and cut with one set-up, he can even use PVA and everything will fit perfect. If he's got a router and a laminate trimmer bit, he can even make it pretty.

The angle cuts on the front and the baffle are a little over 8 degrees, but Jim said he left them square and used PL Polyurethane expanding adhesive. No bracing is shown, which is either brave ... or foolish. Jim put triangles in the two back corners (see pic earlier in thread).

This is a great project !!!

~Don
Attached Thumbnails

 

[jbell]

ep2500 works just fine, and has the filter you are looking for. It can be set to 30hz or 50hz via dip switches on the back of the amp.

$720 !!! holy smokes, that's double the price in the states. Any chance you can take an amp home with you?

Also, a crown xti1000 can be had for under $400, and is a very good option. (I love the band manager software)


edit: checked ebay.au
http://cgi.ebay.com.au/NEW-BEHRINGE...ViewItemQQptZAU_Pro_Audio?hash=item439b4f1fdc

You could always series/parallel your subs on one channel for a 4ohm load, and run your tops from the other.

 

[juxta]

ep2500 works just fine, and has the filter you are looking for. It can be set to 30hz or 50hz via dip switches on the back of the amp.

$720 !!! holy smokes, that's double the price in the states. Any chance you can take an amp home with you?

Also, a crown xti1000 can be had for under $400, and is a very good option. (I love the band manager software)

I would bring one back but I'll be a little low on cash by end of trip and I'm already not bringing checked bags so I can bring back a 15" bass driver and a horn for my Klipsch! Could ask my girl to leave her bags over there!!!

Na not gonna happen

Btw the GTO costs $112 USd a piece
$448 for 4
$708 posted (off ebay seems like a constant source)

Or
$194 in Oz
$776 for 4
$849 posted!!!

xti1000 cost $1300 Ozdollars! (first look)

Everything costs more down here.. Fuel costs me $1.50 a litre!!!

A XTI4000 on ebay: Crown XTI 4000 XTI4000 3200W Power Amplifier LAST ONE! - eBay, Rack Gear, Pro Audio, Musical Instruments. (end time 13-Nov-09 16:22:13 AEDST)

Also I can keep all four centred in front of booth, only needed to split if tall single fold bins....

Checked my music an found that most peaks at about 50hz too, I think I eq out most kicks/bass below 35hz...

 

[jbell]

I think a plan is forming, that ebay ep4000 for au619, and a set of 4 of the JBL drivers in the big cabinet.

The only other thing I'd caution you on, is the quality of your plywood. I used arauco 7ply which was fantastic. Even with that quality of ply, my front vibrated a little bit, and I should have put in a triangle brace from the top/front.

http://www.diyaudio.com/forums/subwoofers/127908-jbells-set-four-tapped-horns.html#post1582984

If you are using typical 'builders' grade sanded 5 ply, I think a pair of triangle braces at 8" spacing , instead of my single brace at 12" would be appropriate. It's amazing how much vibration can happen in a non-braced cabinet. And vibration = less output.

Use the best quality construction adhesive you can get, don't use yellow wood glue. (I used a polyurethane expanding construction adhesive) Also, just before I mounted the driver to the cabinet, I applied a 1/2" wide thin foam weatherstripping (like for windows or doors) to make sure I had zero leaks. Regardless of plywood quality/smoothness, I highly recommend that.

 

[juxta]

I think a plan is forming, that ebay ep4000 for au619, and a set of 4 of the JBL drivers in the big cabinet.

The only other thing I'd caution you on, is the quality of your plywood. I used arauco 7ply which was fantastic. Even with that quality of ply, my front vibrated a little bit, and I should have put in a triangle brace from the top/front.

http://www.diyaudio.com/forums/subwoofers/127908-jbells-set-four-tapped-horns.html#post1582984

If you are using typical 'builders' grade sanded 5 ply, I think a pair of triangle braces at 8" spacing , instead of my single brace at 12" would be appropriate. It's amazing how much vibration can happen in a non-braced cabinet. And vibration = less output.

Use the best quality construction adhesive you can get, don't use yellow wood glue. (I used a polyurethane expanding construction adhesive) Also, just before I mounted the driver to the cabinet, I applied a 1/2" wide thin foam weatherstripping (like for windows or doors) to make sure I had zero leaks. Regardless of plywood quality/smoothness, I highly recommend that.

Yeah no worries I'm pretty keen to find something sturdy, I'd prefer to do it once an do it right than do it badly over an over again!

My practical backgrounds in custom car fibreglass work and boat building so I know a bit about glue an ply, not sure we've arauco down here(think it's South American?) but I'll find something nice.
An old friend runs a boat building supplies place not too far away. I'll check it out..........
I might ask Don to post up the plans/stats an I might ask some more of you as it gets a little closer..


Thanks so much for taking the time out of your day for me!
Cheers

P.S. the hornresp wiki's back up an running now too.
Should make it a little easier