Sunday, August 26, 2012

The Redonkulous Speaker Project

Having overdone it with my little sound system at the last party I did the DJ thing at, it is time to re-equip.DSC_0555
   Enter the Cerwin Vega DX-9’s!
(note: these completed specimens are not mine)
Bob bought himself a pair of DX-9’s back in 1994, and blew the walls out of his living room for about 15 years.  Then he retired them into storage until last week when I took them off his hands.  They were in pretty good shape, the cabinets were easily cleaned up and the electronics seem to have tested good.  The only real problem they have is that the bright orange foam surrounds on the 15” woofer have disintegrated.  Fortunately the re-foaming process is not complicated, and the parts are cheap.  It is a really messy project though!  I neglected to take any pictures of the tear down process, but imagine that orange foam having turned into gritty, sticky paste.  Any bit of it that gets touched falls off and immediately clings to the nearest thing that you don’t want to be smeared with orange!  The easiest way to clean it up seems to be with rubbing alcohol and lots of elbow grease.
dx-9 restore-1
  Here are my woofers, cleaned up and awaiting the arrival of the new foam rings, glue, and center dust caps.    Those bits of paper are shims, slipped in between the magnet pole and the voice coil to keep them aligned while I was monkeying around with them and while I get the foam rings glued into place. The centering of the voice coil is critical to good sound quality and longevity.  These speakers are almost 20 years old, out of production, and nobody makes anything like this nowdays.  If I get this restoration project right, I can expect them to last another 20 years.  Today, all the manufacturers focus on home theater systems, small speakers, and rely on a separate subwoofer to handle the low frequencies.  Nobody tries for epic 2-channel stereo anymore.  =(

Human hearing goes down to around 20hz, and as high as 20,000hz.  The frequency response of this speaker runs down to 35hz, very nearly subsonic.  Put enough power into these things, and you could jiggle all your internal organs around like jello!               dx-9 restore-2
Lets all say it together, “We Don’t Need No Stinkin Subwoofer!”
I think that if you look up “Woofer” in the dictionary, you will find a picture of these humungus things.  That frame is massive cast aluminum, and solid as a rock
dx-9 restore-3

dx-9 restore-5They stand 40” tall, and 18”x18” square. 
The cabinets are basically perfect.  A couple of small nicks and one of the port tubes needs to be re-glued in place. I may also need to replace the 1.5” stand underneath each cabinet.  Also coming my way is a new amplifier to drive these monsters, a used Behringer A500 that I got a good deal on through eBay.  Plus a small mixer board, Behringer Xenyx 802, that can handle a couple of component inputs and a couple of xlr mic inputs.





    Bob’s only condition for giving me these speakers was that I invite him over after I get them fixed up for a “test run” as we attempt to set off car alarms half a mile away.  =)  Maybe I should get some earplugs too…………

3 comments:

Anonymous said...

dance party woooooo!!!!!

Anonymous said...

Very nice job on the speakers and the writing. The glue on my refoam DX9's is drying as we speak. I had to glue port tubes back in place as well will get a chance to listen to this model of Cerwin Vega for the first time when my glue dries.

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