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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Glenn James on September 07, 2011, 09:46:31 AM

Title: Peavey enclosures
Post by: Glenn James on September 07, 2011, 09:46:31 AM
I have a venue with a pair of subs with dual Peavey Lowrider 1808-8 subs in each.
The box has been 'custom designed' and I have never come across a design like this in the past. It is essentially a forward firing ported design but one of the woofers is inverted and placed 4 inches further back than the other side, wired out of phase. The port exits through the centre between the 2 woofers and goes to full box height (21 inches, at a guess) and is about 3 inches wide and deep. (21x3x3 port, essentially) The box is roughly 21 x 21 x 42 inches in size. (I havent taken full measurements, just approximations)
It kind of seems to me the drivers are essentially located in free air with no real box tuning or loading. Perhaps I am wrong, not sure.
Is somebody able to tell me this is a tried and true design suitable for these woofers or somebody's science experiment. It has been working 'OK' for a few months but a couple of weeks ago the dj cooked a driver. While we were waiting for parts to arrive the other enclosure was pushed harder than normal and has also developed a rattly driver so more parts are coming.
I find it difficult to get a reasonable tune to this system so I am thinking of rebuilding the boxes to a more suitable and safer enclosure for these drivers.
Title: Re: Peavey enclosures
Post by: Glenn James on September 07, 2011, 06:45:16 PM
The closest thing I can find is something like this. http://www.sirs-e.com/st/dual-passive-contra-inverted-subwoofer-p-5043.html except the port is between the two woofers and like I said above the port extends the entire height of the box and is only a couple of inches deep.
Title: Re: Peavey enclosures
Post by: John Livings on September 07, 2011, 09:00:12 PM
Hi Glenn,

If you don't get an answer here, try poasting at;

http://forums.peavey.com/viewforum.php?f=26&sid=2a5a20943ec1b6e93d141f153d53606b

Regards,  John
Title: Re: Peavey enclosures
Post by: Craig Leerman on September 08, 2011, 12:49:18 AM
While I can't exactly picture the box you are describing, here is a commercial EAW subwoofer that inverts one of the drivers.

Title: Re: Peavey enclosures
Post by: Douglas R. Allen on September 08, 2011, 05:20:44 AM
I have a venue with a pair of subs with dual Peavey Lowrider 1808-8 subs in each.
The box has been 'custom designed' and I have never come across a design like this in the past. It is essentially a forward firing ported design but one of the woofers is inverted and placed 4 inches further back than the other side, wired out of phase. The port exits through the centre between the 2 woofers and goes to full box height (21 inches, at a guess) and is about 3 inches wide and deep. (21x3x3 port, essentially) The box is roughly 21 x 21 x 42 inches in size. (I havent taken full measurements, just approximations)
It kind of seems to me the drivers are essentially located in free air with no real box tuning or loading. Perhaps I am wrong, not sure.
Is somebody able to tell me this is a tried and true design suitable for these woofers or somebody's science experiment. It has been working 'OK' for a few months but a couple of weeks ago the dj cooked a driver. While we were waiting for parts to arrive the other enclosure was pushed harder than normal and has also developed a rattly driver so more parts are coming.
I find it difficult to get a reasonable tune to this system so I am thinking of rebuilding the boxes to a more suitable and safer enclosure for these drivers.

I had 4 of the Peavey DTH218b subs.
The 4 block close to the top in the image link were mine.
Not a bad box. Sounds more like someone is over driving the box than a box problem. May be better to get the drivers TS and check the box in WinISD.

www.google.com/search?q=peavey+dth218b+image&hl=en&rls=com.microsoft:en-us:IE-SearchBox&rlz=1I7GGLL_en&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=0IdoTvKQKbPE0AHiofnwCw&ved=0CBkQsAQ&biw=1012&bih=617

Douglas R. Allen
Title: Re: Peavey enclosures
Post by: Brad Weber on September 08, 2011, 01:13:52 PM
I had 4 of the Peavey DTH218b subs.
The 4 block close to the top in the image link were mine.
Not a bad box. Sounds more like someone is over driving the box than a box problem. May be better to get the drivers TS and check the box in WinISD.

www.google.com/search?q=peavey+dth218b+image&hl=en&rls=com.microsoft:en-us:IE-SearchBox&rlz=1I7GGLL_en&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=0IdoTvKQKbPE0AHiofnwCw&ved=0CBkQsAQ&biw=1012&bih=617 (http://www.google.com/search?q=peavey+dth218b+image&hl=en&rls=com.microsoft:en-us:IE-SearchBox&rlz=1I7GGLL_en&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=0IdoTvKQKbPE0AHiofnwCw&ved=0CBkQsAQ&biw=1012&bih=617)

Douglas R. Allen
DTH218 and DTH218B product data sheets:

http://www.peavey.com/assets/literature/manuals/80301572.pdf (http://www.peavey.com/assets/literature/manuals/80301572.pdf)
http://www.peavey.com/assets/literature/manuals/80302409.pdf (http://www.peavey.com/assets/literature/manuals/80302409.pdf)

Both drivers are loaded by the box with the drivers in a push-pull arrangement and the drivers wired out of polarity.  One thing to note is that the driver connections are brought out individually so you might want to verify that they are properly wired and that you're not inverting the polarity for the driver that is internally inverted.

What are you using to drive these?
Title: Re: Peavey enclosures
Post by: Glenn James on September 08, 2011, 08:52:12 PM
Thanks Brad, knew somebody here would have an answer...
They are exactly the box that has been copied. How deep are the ports in your boxes? I have no issues regarding phase etc, everything works and is wired properly. I found somebody who thinks they know better has altered the settings on the driverack, completely eliminating my HPF and limiter setings which have worked fine for 12 months plus. Went there yesterday and realigned the system to sound nice and clean with background music with only a small bump in the low end. If the DJs really want heavy bass, there is a knob on their mixer to add more. Woofers at their own expense.
Being driven by Peavey CS3000 for each pair.
Title: Re: Peavey enclosures
Post by: Paul G. OBrien on September 12, 2011, 10:37:41 PM
I have a venue with a pair of subs with dual Peavey Lowrider 1808-8 subs in each.

Heads up.. there are no less then 3 different PV 1808-8 drivers...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=294-307
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=294-3106
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=294-3108

and neither of them are as capable as the Lowrider...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=294-301