kjellarne Posted January 4, 2014 Share Posted January 4, 2014 Can someone explain the L3S polarity selector for me? Under what circumstances would I want or need to invert the signal? And: How do I know if 80 Hz, 100 Hz, 120 Hz (or turned off) Xover Frequency on the sub should be used? kjell Quote Link to comment Share on other sites More sharing options...
dboomer Posted January 4, 2014 Share Posted January 4, 2014 The polarity switch inverts the polarity of the speaker. In other words it determines whether the first impulse to the speaker moves the speaker pushing out or pulling in. The idea is that you may switch this to get the top and the sub working together in sync ( so they are both pulling or both pushing). It doesn't really matter which way they go but when they are out of sync you will likely lose bass output. When using an all Line 6 speakers this is done automatically via L6 link. But since there is no standard for how this should occur, it may be different from brand to brand. So the switch allows you to blend the L6 subs with other brands of tops no matter how they are wired If you are curious to try this out what you do is play a single sine wave tone at or very near to the crossover frequency you have selected. While playing the tone flip the switch. Now depending on a number of things you may hear the tone get louder or softer ( there may also be no change). Just leave it switched to which ever way gives you the loudest output. Don't worry too much about this as you may not actually hear a difference. The L3 subs offer multiple crossover frequencies again so they can be matched to a number of tops , both Line 6 and other brands. This is mostly a subjective decision and depends on your expectations as well as how it matches up to the type of music you play through the system. There's really not a right way and a wrong way but it will make a difference to the way music sounds through the system. Just pick what sounds the best to you. As a general starting point you use the lowest point if you are using top boxes that have a lot of lows ( typically 15" woofers) and higher points if you have 12's, 10's etc. My personal preference when you have music with vocals is to set them so that there is very little of the vocals that get down into the subs. So this depends on your singers capabilities. It would be different depending on whether you have bass, tenor or alto voices. This doesn't apply if you are doing all instrumental music of course. Quote Link to comment Share on other sites More sharing options...
kjellarne Posted January 5, 2014 Author Share Posted January 5, 2014 Great, that cleared up a lot! kjell Quote Link to comment Share on other sites More sharing options...
calou42 Posted February 8, 2015 Share Posted February 8, 2015 Hi, A question with the crossover We are using the Line 6 system (M20D, two L3S and two L3M) with the L6 Link. We connect in the M20D the drum, guitar, vocals and sometimes the bass. If we set the crossover to 80, 100 or 120, we lose a lot of power of the L3S, and we have to turn the master of the M20D up. In the manual, it is notice that with the L6 link the crossover is set automatically. So does the croosover must be set on "OFF" ? Thanks for your answer! Pascal Quote Link to comment Share on other sites More sharing options...
dboomer Posted February 11, 2015 Share Posted February 11, 2015 You lose power in the sub compared to what? Quote Link to comment Share on other sites More sharing options...
calou42 Posted February 13, 2015 Share Posted February 13, 2015 When the crossover is on, the voice and the guitar don't trought out the sub, so if we want more power without boost the master, we must cut it... Quote Link to comment Share on other sites More sharing options...
dboomer Posted February 13, 2015 Share Posted February 13, 2015 You will get more interference and distortion if you do. It is not intended to work that way Quote Link to comment Share on other sites More sharing options...
calou42 Posted February 15, 2015 Share Posted February 15, 2015 So the L3S works only with the drums and the bass? When do you set it on "off"? Quote Link to comment Share on other sites More sharing options...
Rick_Auricchio Posted February 15, 2015 Share Posted February 15, 2015 This is typical of a subwoofer: it's designed and crossed-over to reproduce only the lowest frequencies. Quote Link to comment Share on other sites More sharing options...
dboomer Posted February 15, 2015 Share Posted February 15, 2015 Let me greatly simplify a couple of issues ... Woofers tend to move back and forth much further than mid range and upper drivers. If you let a woofer reproduce both a very low and a medium high frequency at the same time it creates something called "Doppler distortion". Just to keep the math simple imagine your subwoofer was reproducing both 100 HZ and 1000Hz at the same time. To produce the 1000tone the speaker moves back 1000 times per second but doesn't travel with much distance. But the 100HZ tone moves 100 times per second... 50 times forward and 50 times back. But at this frequency it travels a distance about 20 times further then the cone has to move to produce 1000HZ. So what happens is your 1000HZ tone gets reproduced 50 times while the speaker is pushed all the way out and 50 more times while it's all the way back. That creates a Leslie speaker type effect called Doppler distortion and you can hear it. It gets much worse as the distance traveled to reproduce 50hz takes 80 times more distance. The second problem is that any time two speakers reproduce the same frequency as each other but are physical separated ( even by a few inches) it causes comb filtering. Comb filtering causes notches to be cut out of your program material. This is more audibly apparent at lower frequencies than at higher frequencies. So by crossing over and not overlapping you can keep this to a minimum. If you chose not to crossover then truly some of the frequencies produced at the same time would be slightly louder but some would be greatly reduced and even eliminated entirely. It's usually not a good compromise. Quote Link to comment Share on other sites More sharing options...
calou42 Posted February 18, 2015 Share Posted February 18, 2015 Thanks for this "well-imaged" reply! Now i have understand the problem with switch off the crossover! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.