qsc rmx 2450 to 12 speaker setup.

[Steve Denenberg]

now it dips in power, and shutting off for 30 sec, its really weird, but i have not rewired the speakers yet and have not got a crossover, im wondering if 14awg cable is good for all the speakers longest run about 100 feet with 4 ohm b52. im just wondering if three rmx 2450 is enough for 10 to 12 4ohm speakers? And how to hook up 4 powered subs to them. i want to get new speaker cable and a crossover. basically alot can go wrong, the yellow lights come on each amp and never go to red, but shuts off and drops in power. I run my mixer dj stereo in the rack mixer an american audio 8 channel mixer then xlr out that into a behringer eq stereo out that, into 1 qsc amp then i go out that into other amp and so on. any more ideas? thaks steve. ps do the yellow lights have to be on at all or just keep the gain knob almost all the way down and turn up the mixer output?

When the music is playing the yellow ones are blinking (right?) which indicates you're getting a signal, the red light is the Clip light and it should only be blinking on the hardest hitting song only in the most extremely demanding situation. In reality it is ideal to never let those lights come on, but sometimes when you're really pushing the amp it might happen. Slightly blinking a clip light at the most extreme volume demands is acceptable, but a constant red light is not a good sign, and can lead to damage. A signal that is clipping is basically going beyond the natural range of the original audio signal, and can produce sound levels, and sound waves that will damage your speakers, and will just sound like crap coming out too. Plus you're risking frying your amp. Rule of thumb is to stay out of clipping (meaning stay out of the red) on all connected equipment that has any type of VU meter, level indicator, or clip lights. Including the mixer, EQ, crossover, amps, powered speakers/subs, and anything else with a volume, or gain control.

If you're not getting enough volume out of any specific sound system without clipping then you need more power, and/or more speakers.

It can be a headache setting up a system to stay out of clipping, but having another user come in and max out the volume at the mixer so it's clipping anyway while you're not there. Maybe you should tape a note to the mixer near the VU meter that says "DON'T LET THIS LEVEL GO IN THE RED - DON'T CHANGE ANY OTHER EQUIPMENT SETTINGS." Just by turning up the bass you can send things into clipping.

Good luck.

Oh yeah! Here's a link to the user manual for your QSC RMX amps: http://media.qscaudio.com/pdfs/manua...ser_Manual.pdf
Maybe print it out when you can, and leave it with the amps.

[Ken Heath]

[IMG][/IMG]

Simple: Two 4ohm speakers in series on each channel of the amplifiers. (4+4=8, therefore each channel will see a normal 8ohm load)

Split the signal and run it to the powered subs.

[Conanski]

now it dips in power, and shutting off for 30 sec,

I'll say it again... these amps are NOT designed to run at 2 ohm continuously!!!! I suggest you verify the impedance of the speakers with a multimeter, disconnect the wires at the amps 1 set at a time and measure it with a multimer, if you get anything less than 3ohms you're going to have to rewire all the speakers in series pairs it's as simple as that.

[hippydog]

With 12 speakers its most likely they wired it 3 speakers per channel.. (easy way to find out is connect just one cable and see which speakers work, then do the same for the other 3 sets)

Can you take a picture or figure out how they wired them?
I'm curious if they ran them in parallel or series..
in Series it would be 12 ohms (which isnt horrible), and in parallel it would 1.33 ohms (below the capability of the amp)

in your first post you said they had 3 RMX amps right?
do you know what they were using the third amp for?

or do you think all three were used to power the tops?

Also I still need to know the models of the subs..

the cords have two wires each correct?
ones positive and ones negative (it may be a black and white wire)

What kind of connectors are on the back of the speakers? 1/4" phone? Neutrik NL4?

if it was me..
I would first figure out the system and how they ran it and wired it..
then I would getting every thing working again, correctly..
then I would start making improvements, (run all the subs in mono off an active crossover, decide if the tops can be moved to better locations, rewire and reorient the speakers so the bar is "zoned" , etc etc)

then I would say your next step is to start tracing the wiring.. (make sure which speakers are connected to which wires)

I would also be interested in the direction the speakers are facing, as your diagram was a little unclear on that.. (again, a picture is worth a thousand words)

did you say you got the subs working or no?

now it dips in power, and shutting off for 30 sec, its really weird, but i have not rewired the speakers yet and have not got a crossover, im wondering if 14awg cable is good for all the speakers longest run about 100 feet with 4 ohm b52. im just wondering if three rmx 2450 is enough for 10 to 12 4ohm speakers? And how to hook up 4 powered subs to them. i want to get new speaker cable and a crossover. basically alot can go wrong, the yellow lights come on each amp and never go to red, but shuts off and drops in power. I run my mixer dj stereo in the rack mixer an american audio 8 channel mixer then xlr out that into a behringer eq stereo out that, into 1 qsc amp then i go out that into other amp and so on. any more ideas? thaks steve. ps do the yellow lights have to be on at all or just keep the gain knob almost all the way down and turn up the mixer output?

did I mention I am not only an electronic engineer (tech) but also used to do professional installations of low voltage wiring?.. (including full bar lights and sound, and theater installations)..
I'm more then willing to help you..
but I need you to give me the correct information,
cause I am not going to give random advice until I know more..

First thing you need to do is to trace the wiring and draw up a diagram..
Also take some pictures of the wiring (specifically the booth wiring and the wiring to the back of the speakers)
You also need to find out which speakers are connected to which wires..

[hippydog]

I suggest you verify the impedance of the speakers with a multimeter, .

Impedance of a speaker can not be measured with most regular multimeters..
The resistance (R) of the coil is not always the same as its 'Z' Impedance..

Having said that, you can do a basic check of the wiring using a regular multimeter, as generally an 8 ohm (Z) speaker will read around 4 to 6 ohms (R) , and a 4 ohm (Z) speaker will read around 3 (R) ohms..
(not something I would recommend for a newbie as 1.) most cheap meters are not very good at the low ohms, and 2.) it will just confuse most people unless they know how things are wired)
As conanski suggested it wouldnt hurt to see how much resistance is on the wires at the amps (wires disconnected from the amp).. THIS IS NOT THE IMPEDANCE OF SPEAKERS, but the resistance should be greater then 4 ohms (heck, the wire itself should add an ohm or two).. It doesnt give you all the answers but its a quick check to look for a starting point.. but without know how the speakers are wired its a bit meaningless.

If the plate of speaker says 4 ohm, then the speaker is most likely 4 ohm.. (unless they completely redid the speakers, but judging by how they did the wiring I seriously doubt that..)

http://www.bcae1.com/resvsimp.htm

http://www.prestonelectronics.com/audio/Impedance.htm

[Conanski]

Impedance of a speaker can not be measured with most regular multimeters..

Hippy.... as an electronics technologist and life long speaker builder I'm well aware of that ... I was simply attempting to give the OP an easy way to asses the system as it stands.

[hippydog]

Hippy.... as an electronics technologist and life long speaker builder I'm well aware of that ... I was simply attempting to give the OP an easy way to asses the system as it stands.

you replied to fast
I was editing it probably as you posted.. Your "method" is correct, but you know how misinformation in this forum sometimes becomes 'fact''

[djtunes]

Hire a professional. Not to be rude. Do one of 2 things.

List all of the existing gear by Mfg., & Model, including playback decks (players= CD decks or Computer Controllers) mixer, eq, EVERYTHING in the entire chain. Diagram the room with dimensions, and pictures of almost everything (of room and gear + pics of ID marks on the equipment & speakers), then be ready to replace or accurately remove and rerun all wires or cords to everything. Not until you're 100% sure exactly what wire goes where will you know if you got it right. The speakers might not even be all original inside the box. ??? Who knows?

The someone on here might actually post advice that someone would usually charge a lot of money to come and do it their self.

Or hire a local professional install company to do it for you.

[hippydog]

List all of the existing gear by Mfg., & Model, including playback decks (players= CD decks or Computer Controllers) mixer, eq, EVERYTHING in the entire chain.

For what reason? until he decides to add more equipment like a crossover or DBX that information is meaningless..

Do we need to know the model numbers of the subs? yes.. because they are active and that will help with the correct setup.. do we need to know the CD player model #? no..

Diagram the room with dimensions,

again, for what reason?.. if he wants to start moving the placement of the speakers that becomes important..
for now the smartest thing is to just get the system in working order before he starts fracking with things.

Always..ALWAYS start with a good known working system, before you start making wholesale changes..

(unless you are a professional like bill at ESC whose job is to redo complete systems on a daily basis)

then be ready to replace or accurately remove and rerun all wires or cords to everything.

everyone is assuming that the original installation was wrong.. In my experience its not the original installation thats wrong, its the people who came in later and messed with it and changed and added things that make it wonky..

most bar owners dont like spending money.. they also dislike losing money.. (a system thats down becuase someone thought it was a good idea to rip all the cords out, probably wont make em to happy).. Again.. get the system in working order first (using the original setup and wires as much as possible)... THEN start fracking with it..

The speakers might not even be all original inside the box. ??? Who knows?

possible, but unlikely.. I've only seen that myself twice and both times it was more of the case the original driver wasnt available.. (and the replacement wasnt horrible or wrong, just not original)

Or hire a local professional install company to do it for you.

Thats always the best answer..

on the other hand some bar owners are pretty cheap

and if Steve D can pull this off, thats a pretty nice feather in his cap..

[Steve Denenberg]

ok the latest i went to dj last night no shut offs or bad sound actually sounded great but i know its not right yet. All your answers and ideas are fantastic. Um i do think i would go and take pics of all the equip for you guys speakers and racks stuff. I dont know what is parallel or series. I know i should and i probably do just dont know what it looks like... lol um im a dj and graphic designer not a av install guy. I Think it would be great if i could just run new cable to each speaker and run it into the amps. Sounds easy but its not when there is an existing system installed. You guys are right about its not really the initial install its all the morons messing with it and broken gear as abuse has big part to do with it, turn up gains, broken knobs, grease and dirt dust in the fans with no cleaning for years this leads to broke down equip and im just trying to help get it running right. And yes bar owners are cheap. example owner just bought to big *** fans 16,000.00 on fans but wont spend a few thousand on new audio equip, funny how that is. The times when he makes the most money is fri and sat nights and when the systems down or sounding like crap people leave and dont enjoy themselves, So i understand both sides. I will try to get all the info for you guys to point me in the right direction as this is an ongoing dilemma for me right now, i did talk to some pros and they said they do not fix or qoute on exisiting systems only new installs. it is to many variables which i understand as well so stay tuned boys, oh yeah one of the qscs amps is not hooked up only using 2 at the moment. thanks again