Pa gurus to the rescue

[Crowder]

I just bought two EV SB120A powered subs. I can't find a manual online, so I'm hoping to get some help from you fine folks.

The speakers have a power switch and a level control. There is a Neutrik line level input. There's also an signal out jack, which for some reason is XLR male and not Neutrik. There's also a gain control.

Our mains are EV SX300's. The signal chain for the mains is basically a mixer to an EQ to a power amp (we also use a compressor and verb but they are in the insert/loop chains of the board). Since the subs require a line-level input, I'm guessing they will either go between the EQ and the power amp or be fed by a split off that part of the chain. However, I don't know the easiest way to roll off the lows going to our mains that will now be handled by the subs.

1) I could get a crossover, which would be fine with me. But...

2) I wonder if a mini-crossover is built into the subs so that the Out jack doesn't pass the lows along to the next part of the chain. I don't know how to tell besides trial and error, and I don't have access to the rest of the system before our next gig.

Anyone who has any experience with powered subs, or knows how to get a manual for the EV SB120A's, please chime in.

[Crowder]

To clarify, I just looked at the back panel and it clearly states that the output is FULL RANGE and LINE LEVEL. I suppose that ends the mystery of whether a crossover is part of the deal.

[steve V. johnson]

OK, here's some stuff....

EV manuals directory

http://archives.telex.com/archives/EV/Speakers/Service%20Manuals/

Sb120 series service manual

http://archives.telex.com/archive....tes.pdf (http://archives.telex.com/archives/EV/Speakers/Service%20Manuals/SB120a%20CE%20Amplifier%20Service%20Notes.pdf)

Amplifier service notes

http://archives.telex.com/archive....tes.pdf (http://archives.telex.com/archives/EV/Speakers/Service%20Manuals/SB120a%20CE%20Amplifier%20Service%20Notes.pdf)

"Service data"

http://archives.telex.com/archive....ice.pdf (http://archives.telex.com/archives/EV/Speakers/Service%20Manuals/SB120%20&%20SB120W%20Service.pdf)

I don't know if this stuff is useful... now to go read some of it...

stv

[steve V. johnson]

Here's the System 200 manual that has sections about the 120 subwoofers.

http://archives.telex.com/archive....ual.pdf (http://archives.telex.com/archives/EV/Speakers/Owners%20Manuals/System%20200%20Owners%20Manual.pdf)

I haven't read this stuff yet...

I see, tho, from some of the amplifier diagrams, that there is a low-pass filter in the subwoofers, but I didn't look
closely enough at the schematics to tell what the crossover frequency is.

OK, I looked thru that one and there are hookup diagrams and other stuff that you may find useful, but not real freq specs on the X-over ...

It's as close as it gets, maybe...

stv

[Crowder]

Thanks for the search, Steve--I've already reviewed those materials and hit all the dead ends. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif

I've arranged to buy a stereo 2-way crossover. I think I'm going to use one sub out front with the main mix and one on the backline with the monitor mix (we use really small monitors). My hope is that our bass player will be able to run direct or at least through a DI box. Right now he's using a small amp with a line out to the board, but it makes an already-cramped stage that much worse.

[steve V. johnson]

Ah, well.,.. Sorry for the redundancy.

Yeah, it really looks as tho these things are sort of orphaned outside of the system and without the system controller...

I think that if you look really closely at the schematic, somewhere you will be able to find the values of the components in the low-pass filter. I wish I could suggest the corner frequency, but these things are all over the place...

If you figure it out, please let me know? :-)

I hope your applications work well for you. It seems a good way to use 'em.

All the best,

stv