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Getting a Crossover need advice to clear some things up.


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  • Getting a Crossover need advice to clear some things up.

    This is my first post on this forum. I love this website and have used it to purchase many a item so far.

    I've been putting this PA system together for a while for my band and I've finally got a pair of subs (EV LF215's). They are going to go with my mains or "top's" i guess i could call them (EV s-152). I also have a pair of RC90a's that i may OR may not use depending on the feedback i get here.

    Please forgive me if I'm crapping this post all up.

    I'm going to buy a DBX 223xl crossover and has the option to "mono sum out". Can I do this with my LF215's? I looked at the EDS and i didnt see anything about being able to but i think that option may have been designed after these were made. I really don't under stand what the mono sum out does truly but since i'm running a mono mix all the time (its a mobile pa and its just easier that way) i figure its a good thing. at the same time i dont want to do anything harmful to the only subs i have since i am a poor musician ... and because my wife has my balls in my wallet in her closet

    In addition... Should i bother with the RC90a's? or just let the highs ring out of the ev s152's?

    some information about these components to maybe help you and save your time.

    EV LF215's
    usable frequency response
    40hz - 5khz --- is this good? i means its pretty low which i think is good.
    spl @ 4ft 129 db @10ft 95 db.

    6db down possible beamwidth crossover frequencies ( i have NO idea what that means.. loss of 6db and something with beamwidth)

    In case i wrote it all wrong =(

    EV s152's
    freq response 55hz - 20khz


    ev rc90a
    only item that really gave a "crossover" frequency. 800hz

    Thank you for any help and sorry for the LONG post.

    I feel as though i should leave the Horns out of it but your info may help. I've never used a crossover but i feel DBX will do me right. Just need a steer in the right direction.

    again thank you kindly

    derik =)

  • #2
    The DBX is a decent unit.I use one.To start , I would just use the passive crossover in the tops to run the high-end.If you are running mono,just use one side of the crossover.After you feel like you got it down,then add the horns,and go 3-way.You don't say what degree of experience you have in this field,so I am assuming very little.If you have some experience,and are not trying to run this rig from the stage while you play/sing,you may opt to go 3-way mono right out of the gate.


    • #3
      Just use the EV S152's and LF215's. I'm not familiar with the subs you have but I had a pair of S152's for a few years. They sound great and got loud enough with little power. The drivers are an EV Force 15 and a DH2010 crossed at 2.2k, nothing special but EV stuff just sounds great IMHO. I have the 12" version I'm looking at replacing with SX100/300 if the money falls out of the sky and I don't need to eat that month.

      Use Left channel only, High and Low out only. Leave out the mono sum for now. If you run stereo mains and want mono subs that is where that feature comes in handy.

      bassist and sound reinforcement


      • #4
        I run stereo. I used the summed out on my subs because my amp was smaller and I felt that running the amp bridged to the two 8 ohm speakers was going to use the most power from the amp. This is based on my self taught logic. I bought another larger amp and recently did a gig running the subs stereo but this time I added two subs for a total of four. Two per side, 4 ohm load per side.

        If you've never used a cross over. It might take some time to dial it in right. There's quite a few adjustments to make but nothing difficult, just make gradual changes and use your ear.

        I recently found out that the phasing button makes a huge difference, so try it both in and out and you will hear one position giving you much more low end. I would swear my stuff is all phased right but I engaged the phase button and got at least 25% more lowend. I need to experiment with this some more also examine my cables and make sure nothing is reversed.

        Good luck.
        Uhhhhhh the "Money for Nothing" program was such a huge success we ran out of money. Uhhhh but don't worry, we're gonna uhhhhhh print more money and extend the program.


        • #5
          Thank you all for taking time out of your days to help me better understand what I'm doing.

          I got the crossover today for $100 buck-a-roo's and since getting and reading this post have realized a few things.

          I appreciate your time and your knowledge.

          I love EV... well Michigan EV.

          One day I'll be able to afford some sweet tops and subs. Probably the same day my wife decides she's had enough.

          On another note.

          Whats a good crossover over point for my subs to mids/high's?

          since the LF215's go to 40 - like 5khz would it be like 300hz? I guess i'll just have to see what sounds best.

          again thank you guys so much. To be able to tap into the wealth of knowledge this forum provides is a true treat.



          • #6
            Start at 100Hz. and experiment from 80 to 120Hz and see what sounds best. I'm betting 100Hz will do just fine. Anything above 120-150 Hz will start sounding like a low midrange muddy mess. You don't want to go there.
            HC Geezer Brigade Trooper #51


            • #7
              Yup, 100Hz is always a good starting point for subs. The play with it from 90-120Hz or even from 80-130 Hz. If using 12" tops, 150Hz isn't out of the question.

              Many speaker specs go to the -10dB point, not that useful an output. Plus the bigger or wider they advertise, the better it SEEMS. 300Hz is where the lower 15" in dual 15" TOPS cuts IN. It's also where the Yorkville U15 tree way uses it's single 15". So, in a nutshell, crossing subs at 300Hz is like losing half of you tops' woofer's capacity ;>(



              • #8
                Oh and engage the 40Hz High Pass Filter on that 223XL.
                HC Geezer Brigade Trooper #51


                • #9
                  when you say engage the 40hz filter do you mean for the subs or for the mid/high range?


                  • #10
                    Interesting, I used a LF-215 as a bass cab for years.
                    Dillybar 13 july 2008.
                    "I do not expect you to lift one of your lazy fingers to find the proof that I am right."


                    • #11
                      yah i got these in a trade. They sounded good the other day i wanna mike the drum set up and hopefully they sound as good as i think they do. EV has treated me well so far.