Members CT6Mblack Posted February 11, 2007 Members Share Posted February 11, 2007 Ok, we have a Behringer PMH5000 powered mixer and 3 Carvin LM15 475W speakers. I'm wondering what is the best way to set these up. The mixer has two outputs (2 x 400w or 800w bridged) and we're planning on using all three of these speakers as the main speakers. I don't think any stereo/panning effects will be used much so that's not an issue. So does anyone have any insight as to the best way to hook these all up? Thanks a lot! Link to comment Share on other sites More sharing options...
Members Al Poulin Posted February 11, 2007 Members Share Posted February 11, 2007 Depends what you want to do with it. Why 3 speakers? If the setup is simply as a FOH sound sytem, get one more speaker and you can connect (daisy-chain) 2 cabs per channel - giving you an optimum 4 ohm/channel load. If you were hoping to use this setup as mains and monitors, you will have to connect it a different way. Maybe using one side of the powered mixer for mains and the other for your monitor. Usually though, it is better to have a seperate amp running monitors. Again, this depends what you want in your monitors and what you are trying to achieve with your system... Al Link to comment Share on other sites More sharing options...
Members prosigna Posted February 11, 2007 Members Share Posted February 11, 2007 I cannot think of any good way to use all three. Two in one channel at 4-ohms and the third in the second channel at 8-ohms is as close as you will get to using all three for FOH. If you daisy chain all three you are running at 2.67-ohms. That amp would not like that (especially in bridged mode). Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 11, 2007 Author Members Share Posted February 11, 2007 i figured as much that it wouldn't be a good idea. But it wasn't me who came up with the setup. I'm just researching it for someone else. So it's definitely not a good idea to go Board->speaker1->speaker2->speaker3 ?So getting 4 total and running 2 out of each R and L would be better? Also would there be any impedance issues? Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 11, 2007 Members Share Posted February 11, 2007 Definately not in bridged mode. In the stereo mode, 2 speakers on 1 channel and the other speaker on the remaining channel is as good as it gets. There will be no perceptable difference in output levels and the speakers will get similar maximum power. Link to comment Share on other sites More sharing options...
Members boomerweps Posted February 11, 2007 Members Share Posted February 11, 2007 Forget this model's bridged mode. It's for ONE 8 ohm speaker.Using the third speaker on the main mix is a waste of time & effort, IMHO.Setting the desk to main + Monitor mode and having 2 speakers off the main amp side (mixer speaker out to 1st speaker, 1st speaker connected to 2nd speaker) means these mains, if 8 ohm, make a 4 ohm load for the 400 watts out of the amp basically split for 200 watts per speaker. Run the extra speaker off the monitor side amp and if an 8 ohm unit, will get about 250-275 watts. (ideally the doubling of resistance from 4 ohm load to 8 ohm load would cut the 4 ohm rated power in half, 200 watts in this case. Amp ratings don't show this when based on equal noise specs.) Link to comment Share on other sites More sharing options...
Members prosigna Posted February 11, 2007 Members Share Posted February 11, 2007 2 speakers on 1 channel and the other speaker on the remaining channel is as good as it gets. There will be no perceptable difference in output levels and the speakers will get similar maximum power. I will have to say that (2) speakers running at 4-ohms on one side and one speaker running at 8-ohms on the other side will be "perceptible" in a L-R situation. 400 to one side and 200-250 to the other. If you clump all three in one spot it could sound fine. Turning one around for stage monitor is a good idea. Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 11, 2007 Members Share Posted February 11, 2007 I will have to say that (2) speakers running at 4-ohms on one side and one speaker running at 8-ohms on the other side will be "perceptible" in a L-R situation. 400 to one side and 200-250 to the other. If you clump all three in one spot it could sound fine. I was assuming all 3 would be used either together or left-right plus a back fill or somewhere-else fill. What I was getting at is that all boxes would get close enough to the same power (200-250 watts) that the boxes themselves would be the same SPL. Also, the powers would be very close since both channels sharethe same power supply rails, so as the rails fall due to the 4 ohm load, the 8 ohm load (maximum) power would fall proportionally. Run below maximum power, there would be virtually zero difference in SPL balance (power) between the two channels. Link to comment Share on other sites More sharing options...
Members 6Imzadi Posted February 11, 2007 Members Share Posted February 11, 2007 Put the third one on it's side in front of the stage. On top of a couple milk crates. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 12, 2007 Author Members Share Posted February 12, 2007 Ok, well if I go with the 3 speakers, and do 2 on one channel and 1 on the other, could you put the 1 in the middle and the 2 on the sides of it? And yes these are all being clustered together, the middle one straight and the two sides ones at angles. It will be mounted from the ceiling/wall (haven't decided yet). As far as what boomerweps said, sorry man, i didn't understand a much of that at all:confused: Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 12, 2007 Members Share Posted February 12, 2007 Be sure to use speakers that are designed for flying (hanging) if that's what you intend to do. Don't "half-ass" this part as people could get hurt or killed if you use poor judgement. Link to comment Share on other sites More sharing options...
Members milesdf Posted February 12, 2007 Members Share Posted February 12, 2007 hm is this for an install? can someone confirm/deny whether the bridged mono with the middle speaker bridged and the outer speakers on individual channels trick would work here? or would the amp explode because of the low impedance? do we have a solid number on its rating, i skimed through the manual and i couldnt find it. Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 12, 2007 Members Share Posted February 12, 2007 That's still pretty low IMO, less than 4 ohms per channel NET. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 12, 2007 Author Members Share Posted February 12, 2007 Here, I'll put it this way:What would be the best setup for main speakers using that board, and not worrying about monitors for the time being. I don't need a brand of speaker, i just need number of speakers, impedance, and an approximate wattage range. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 13, 2007 Author Members Share Posted February 13, 2007 bump Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 13, 2007 Author Members Share Posted February 13, 2007 BUMP again! I need to know what kind of speakers (wattage, and impedance) i need for a mixer that runs 2 x 400w or 1 x 800w bridged. I need to know ASAP as well. We may be making the decision about purchasing them soon! Thanks in advance Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 13, 2007 Members Share Posted February 13, 2007 You don't have much of an option for bridge mode, one x 8 ohm speaker and it better be a good quality one or you've got too much power. For the stereo mode, 2, 3 or 4 x 8 ohm speakers, max of 2 per channel. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 13, 2007 Author Members Share Posted February 13, 2007 For the stereo mode, 2, 3 or 4 x 8 ohm speakers, max of 2 per channel. Really? 2 on 1, and 1 on the other will yield the same output on both channels? Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 13, 2007 Author Members Share Posted February 13, 2007 Also, would you be daisy-chaining the 2 on one side? Link to comment Share on other sites More sharing options...
Members Dark Ice Posted February 14, 2007 Members Share Posted February 14, 2007 It means connecting both speakers, in parallel, on one channel. The same is achieved whether you "daisy chain" the speakers or connect both to the same output channel of the amplifier. Im confused, do you actually have those carvin speakers you mentioned in your first post? Because in your first post you say you have them, and further down the thread you say you're asking for speaker recommendations. In fact, have you bought that behringer board yet? I'm sure if you just lay all your cards on the table the folks here will be much happier to help you. Have you even considered that your proposed carvin speakers, which you propose to cluster, have a 90 degree dispersion? Why isn't the guy who "came up with the setup" choosing these speakers? Surely you cant design a system properly without specifying requirements for the speakers used? How do you know you wont have feedback or dispersion issues? How do you know your system will produce adequate SPL? If you were just putting these speakers on a couple of poles I wouldnt worry because you could just move them about if you {censored} up, but it sounds like you're about to invest a lot of money hanging these things permanently without a clue as to what you need to buy or how to place it. I know from first hand experience what can happen when a church system is installed by a non-professional. Please save yourselves some money and headaches and get someone to do this properly Steve. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 14, 2007 Author Members Share Posted February 14, 2007 Alright, ya know what? I'm gonna come straight out and say... I DON'T KNOW EVERYTHING!!! Thus... I ask questions. Alright? I'm just making sure we don't make a mistake. All I'm really trying to do is make sure we don't end up blowing up our mixer (which we do have by the way) because we try to run a lower impedence load than it can handle. This is an area I don't know a lot about, neither does the guy wanting to buy the speakers. They were recommended to him by a guy who supposedly knows what he's talking about. I was just verifying that 3 speakers would work with the board. Is that so wrong? Link to comment Share on other sites More sharing options...
Members Al Poulin Posted February 14, 2007 Members Share Posted February 14, 2007 Alright, ya know what? I'm gonna come straight out and say...I DON'T KNOW EVERYTHING!!! Thus... I ask questions. Alright? I'm just making sure we don't make a mistake. All I'm really trying to do is make sure we don't end up blowing up our mixer (which we do have by the way) because we try to run a lower impedence load than it can handle. This is an area I don't know a lot about, neither does the guy wanting to buy the speakers. They were recommended to him by a guy who supposedly knows what he's talking about. I was just verifying that 3 speakers would work with the board. Is that so wrong? You won't blow anything up as long as you run the mixer in stereo mode (don't bridge it). Plug 2 speakers on one side and one on the other. One side of the amp will see a 4 ohm load while the other will see an 8ohm load. It will run perfectly fine. Eventually, if you want to balance things out, buy another one of those speakers and add it to the side with only one cab. Al Link to comment Share on other sites More sharing options...
Members Dark Ice Posted February 14, 2007 Members Share Posted February 14, 2007 Alright, ya know what? I'm gonna come straight out and say...I DON'T KNOW EVERYTHING!!! Hey hey man, calm down. Chill.I'm just warning you that there are many potential pitfalls in what you're trying to do here. Many people think they can just hang speakers wherever they like and the system will work and thats all there is to it. I dont blame anyone for thinking that if they havn't had any real experience with SR systems. But some people get a little bit of knowlege with 'some' audio 'stuff' that might be related, but dont actually have a clue whats required of a real audio installation, and dont acknowlege that they're essentially gambling with other peoples money when they recommend equipment. I see it ALL the time, and I cant say for sure, but I think your "guy who supposedly knows what he's talking about" might be one of them. Truth of the matter is that there are loads of things that can go wrong. It might work, just randomly hanging your speakers wherever you like. It has for loads of people. I also know that $thousands if not $millions have been wasted in the past because of a bad installations. What happens after you've paid out for this system and you cant use it because of a terrible feedback problem? Professionals are paid to install a system that WILL work for a room, and you get what you pay for (unless the guys a hack). I'm just saying, I dont know if you have rigging points or anything installed yet, but it sounds expensive and you COULD be on a road to disaster. I also know that you're just trying to do your best for this place and you might have absolutely no control over the installation. I've been there, I know its frustrating. In which case you have your answer (if you can find it in your two threads) - one speaker on one channel, two speakers on the other. Its the best you can do with what you have - if you MUST have a cluster of three. I'd also look for speakers with a 60 degree horisontal dispersion as opposed to a 90 degree dispersion otherwise you'll have more overlap and possible problems with the horns interaction with each other. But to be honest, the best suggestion in this thread has been Agedhorses, get one GOOD 8 ohm speaker and hang it by itself. Theres far less to go wrong and it'll probably sound better. What I meant by saying you should show your cards is that you might have had some better solutions from the members of this board if you had just told us what the room was like (photo would be better), what you have, and what your requirements/budget are. The people on this board ARE professionals and would have the *best* idea what to do without a doubt. Good luck anyway. Steve. Link to comment Share on other sites More sharing options...
Members CT6Mblack Posted February 14, 2007 Author Members Share Posted February 14, 2007 I also know that you're just trying to do your best for this place and you might have absolutely no control over the installation. I've been there, I know its frustrating. It's especially frustrating because we've been dealing with people who don't know a lot as to what's required for a sound system (not the guy who recommended this stuff mind you) and we have a crappy portable fender system. Our deal is that we get feedback from the mics because we have our speakers behind us (not my fault). And we don't have monitors to spare to use. We just want to get the speakers in front of us and some monitors so we can turn our vocals up without getting feedback. Like you mentioned, I'm simply the one just making sure (to the best of my knowledge, which I admit isn't much) that nothing is getting screwed over. I really don't have much effect as to what actually happens. I just hope they know what they're doing. Also, sorry for blowing up a bit earlier. It's just annoying being a noob and dealing with pros. Link to comment Share on other sites More sharing options...
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