Sign In:     

Forum: General Discussion

Topic: Salty Subwoofers

This topic is old and might contain outdated or incorrect information.

Greetings. Please pardon the length of this post.

I just blew a driver in one of my EV dual 15 Force Subs. http://www.electrovoice.com/sitefiles/downloads/force-sub-eds.pdf

It might be time to upgrade. I wasn't all that impressed with them, but they made nice risers for the EV dual 15 Eliminators at 20" high.

I can't seem to find a reconer that will sell me a 4 ohm kit (it's not hard to recone if you're careful). I'll have to send out the pair to let someone else do it. I figure since the other drive coil is probably ready to go, I'll freshen up the cabinet for around $220.

I ran these cabinets over 10 years with no problem. I just switched amps taking them off a QSC 2450 and put them on a Crown XLS 802.

http://www.crownaudio.com/amp_htm/xls.htm
http://www.qscaudio.com/products/amps/rmx/rmx.htm

I'm going to move the QSC back to running the bass. I'm thinking the Crown was a little rough on the driver coils. But maybe not, and nothing lasts forever. I did get good service out of these cubes.

=============================================================================

The upgrade. It might be time to do it right and go with a new pair of EVs. model: Qrx218sblk

http://www.electro-voice.com/sitefiles/downloads/EV_QRx_218S_EDS.pdf

These have the excellent handles that I love with the newer EVs. They have built in wheels (hope they don't rattle), and a pair of these should really kick ass. The downside is the price. These run around $2000 each. Ouch !

An alternate option is to replace the stock drivers in the Force cubes to high performance car woofers like JLs (my initials hehehe). I'm looking for a powerful yet accurate bass, just like a good band, or good nightclub. These car drivers are tough and can move a lot of air.

So I'm a little torn which way to go. State of the art with EV, or experiment with car woofers.

I could replace the EV Force cube stock drivers with 2 - 15 inch 4 ohm car drivers, and see what it would sound like. Or I could go with one 15 (8 or 4 ohm) driver with a passive radiator per cabinet.

I could experiment wiring 2 15's "out" of phase to move lots of "in-phase" air... I don't know if there would be any phasing problem with the Eliminators sitting on top. I could wire them "in" phase and limit the low end due to the small size of the sealed box of the enclosure... having the drivers pump opposite of each other.

I'm sure I would have to re-tune the boxes by changing the port size, or stuffing them with more insulation. A very pain in the butt operation... especially if I use the microphone, signal sweep generator, and oscilloscope. Lots of work. I don't have an anechoic chamber for testing.

I'm guessing with heavy duty JL's x4, or 2 JLs wth 2 passive radiators, we'd be talking around $1000 to retrofit the 2 Force cubes with car drivers. It's a lot of money for an experiment that might not work out.

I would appreciate any insight into converting to car sub woofer drivers from conventional PA drivers. Does it work?

===============================================================================

One other very important question. I run a dual 18" Acoustic woofer on one channel of the bass amp, and parallel the other 2 on the other channel. Both channels have been currently running at 4 ohms.

The EV_QRx_218S's are 4 ohms apiece. That would mean running at 2 ohms for the 2 subs wired in parallel under my Eliminators. The Crown is not rated to run at 2 ohms, but the QSC should.

Can I run the QSC at 4 ohms on one channel and 2 ohms on the other? Or perhaps could I change the wiring of the EV 2185s to a series configuration for 16 ohms? That should give me 2 cabinets at 16 ohms that are paralled to get 8 ohms at the amp.

Or I can make a device to series wire these subs to 8 ohms at the speaker wire ends. Would that work?

The QSC amp "is" rated for 2 ohms and would be putting out 900 watts. Will it heat up more running at 2 ohms than running it at 4 or 8 ohms? Would 2 of these 218s cabinets on one QSC 2450 channel be too much for one channel to handle well?

I appreciate any help,

Jim L.

P.S. This would be a much simplier decision if someone out there would donate 2 of these EV subs to this up and coming DJ/VJ, but I would prefer they send their support to the Japanese victims. The devastation is just stunning.
 
Posted Sat 19 Mar 11 @ 2:58 am
 
Thanks Daz,

Amazing site. I'll be roving round it for dayz.

Wow at some of the woofers these folks build. I can't find a link for it, but back in the 60s Frank Lloyd Wright the "Falling Water" builder once made a speaker horn 20 foot wide at the mouth... out of concrete. How about that for no resonance, and no fold backs.

Thanks for the link.

Jim
 
I would go active if I were you, then you can concentrate on the other stuff you have to worry about lol
 
Thanks Charlie. I thought about going active. I just don't like having to run 2 wires to each speaker. I have enough wires to wrap up at the end of the gig now. LOL.
 
All I run is active. Takes most of the worries out of it. The manufacturers have done all the math for you. Daz's advice is always hands down the best I've ever read...
 
JimmyL-DJ wrote :
Thanks Charlie. I thought about going active. I just don't like having to run 2 wires to each speaker. I have enough wires to wrap up at the end of the gig now. LOL.


They make wires with both the power and xlr in one cable.
 


(Old topics and forums are automatically closed)