ProSoundWeb Community
Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Lounge => Topic started by: Demetrius Garland on July 07, 2012, 05:42:07 PM
-
Hello Board....Ive been trying to help my friend with his subs that he has installed in his church. The problem is they are not putting out half of what they should be, and as soon as you start to hear them a little the amp clip light comes on. Weve tried getting a powered sub and connected to the same output wire from the board (bypassing amps of course) and still not getting at least decent bottom. For our mixing board he is using a Behringer SX2442FX, The subs are Carvin TR1801, and a 2000watt crown amp. He is using the mono out on the board to send signal, the line has a female to female adapter in it to extend it. Its going to a 31Band EQ than to the amp. The amp is in bridge mode. To add to it when we unplug the subs from the amp it still clips. Hes almost maxing out the mono fader just to get a little sound from the subs. This is even with playing an audio CD. The signal at the input is good. Input level on channels are about -5db. Weve been trying to diganose this for a while. Any help would be greatly appreciated!!!! Thanks
-
Hello Board....Ive been trying to help my friend with his subs that he has installed in his church. The problem is they are not putting out half of what they should be,
How do you know, have you measured it or is this like tuning a car and then going by the seat of your pants to judge if you improved the performance?
as soon as you start to hear them a little the amp clip light comes on
The clip light coming on means that the amp is clipping. It may be outputting it's full power, it may not. You'd have to measure the output to know. These speakers won't output much as far as subs go. The continuous capability, before power compression, is about 124dB/SPL at 1 meter for a single sub cabinet. You have not said what amp model this is. Two subs connected in parallel may or may not be O.K. for the amp that's being used. If the amp is actually capable of 2000 watts at 8 ohms per channel, I would not bridge it, I'd run it parallel mono given the mono console feed.
Another potential issue here could be speaker mounting. If they have tried to build these into the structure somehow, most likely they have created problems. It takes a lot of very tight fitting and very dense construction to build in subs so that they work well.
Lee
-
For our mixing board he is using a Behringer SX2442FX, The subs are Carvin TR1801, and a 2000watt crown amp. He is using the mono out on the board to send signal, the line has a female to female adapter in it to extend it.
On the mono output, at the Mono fader is the low pass filter activated and what frequency is set for the filter?
The Mono output on that mixer is an unbalanced 1/4" TS connector, so I'm rather confused on how it is wired. But it being unbalanced with a maximum output 6dB below the balanced main outputs may explain part of of the lower level. And if that is not wired properly to the following device it may explain an even greater difference.
Its going to a 31Band EQ than to the amp.
What are you doing with the EQ? Any chance you may be filtering out all of the low end? And are you doing anything to filter the low frequencies out of the mains?
The amp is in bridge mode.
Are the inputs and outputs properly wired for bridge mode operation?
-
Hello Board....Ive been trying to help my friend with his subs that he has installed in his church. The problem is they are not putting out half of what they should be, and as soon as you start to hear them a little the amp clip light comes on. Weve tried getting a powered sub and connected to the same output wire from the board (bypassing amps of course) and still not getting at least decent bottom. For our mixing board he is using a Behringer SX2442FX, The subs are Carvin TR1801, and a 2000watt crown amp. He is using the mono out on the board to send signal, the line has a female to female adapter in it to extend it. Its going to a 31Band EQ than to the amp. The amp is in bridge mode. To add to it when we unplug the subs from the amp it still clips. Hes almost maxing out the mono fader just to get a little sound from the subs. This is even with playing an audio CD. The signal at the input is good. Input level on channels are about -5db. Weve been trying to diganose this for a while. Any help would be greatly appreciated!!!! Thanks
A couple of things:
First, are you using an electronic crossover in the feed from the mono out jack on the mixer? Using just an equalizer won't really let you set the system up properly. At this point I'd be suspect of how you have the equalizer set-it could be killing the gain structure.
Second, there's a possibility that the two subs are somehow being wired up with reversed polarity between them, which would kill most of the low frequency output.
Also, make sure the on board equalizer doesn't affect the mono output-if it does, and you're cutting the low frequency faders, it would kill the subwoofer output.
Best regards,
John
-
What is placement of subs in room? Both flown in center? Both on ground, 1 per corner?
-
Hello Board....Ive been trying to help my friend with his subs that he has installed in his church. The problem is they are not putting out half of what they should be, and as soon as you start to hear them a little the amp clip light comes on. Weve tried getting a powered sub and connected to the same output wire from the board (bypassing amps of course) and still not getting at least decent bottom. For our mixing board he is using a Behringer SX2442FX, The subs are Carvin TR1801, and a 2000watt crown amp. He is using the mono out on the board to send signal, the line has a female to female adapter in it to extend it. Its going to a 31Band EQ than to the amp. The amp is in bridge mode. To add to it when we unplug the subs from the amp it still clips. Hes almost maxing out the mono fader just to get a little sound from the subs. This is even with playing an audio CD. The signal at the input is good. Input level on channels are about -5db. Weve been trying to diganose this for a while. Any help would be greatly appreciated!!!! Thanks
If the amp is clipping, then 1 of several things is happening.
1: You are simply "out of gas" and that is as loud as it is going to get-maybe you are expecting more out of the system than it can do.
2: You have a short in the speaker line somewhere-causing the amp to see a lower impedance and it is clipping. Disconnect the speakers and take several resistance checks- acrosso the actual speaker wires (you should see the DC resistance of the cabinet). Measure each speaker wire to AC ground-they should both read open.
3: The amp is defective-try another amp
-
Are the inputs and outputs properly wired for bridge mode operation?
My money is on this being the issue.
They may have switched the amplifier into bridge mode, but I am guessing they are not using the two red binding posts for the output.
-
More info needed. What model amp? How old?
-
More info needed. What model amp? How old?
Hello,
I guessing that the poster is got a whole lot of issues that can be addressed.
1.) that unbalanced line out for the sub as Brad posted. straighten this out..
2.) that the gain settings from input to output needed to be addressed. On each channel and buss.
3.) that the poster may have not been sending a proper signal of strength to the mono output for the channels that matter ....ie: Kick, Bass, Keys, etc...
4.) That the EQ is sucking the signal's output...... remove it if it is on the Sub output.
5.) that there is nowhere near enough rig for the gig. Get bigger and better subs and power them appropriately. One of that model of sub is adequate for my theatre room....maybe....
6.) use the net to read the manual of the make and model of amplifier feeding the subwoofer. It is very possible that any dip switches are in the wrong position AND, that you have the amp's output wired incorrectly.
Cheers,
Hammer
-
Hey...sorry so late, the amp is a Behringer EUROPOWER EP2000. The low pass filter on the mono out is activated and the filter is set at 120hertz. As our mains we have 3000 watts driving 6 15s. The church is about 4000sq feet more wider than longer and the subs are positioned standing up in the far outside corners facing straight. I dont have a SPL meter to check levels but from reading LED meters everything is pretty much at unity gain. Speakers are properly plugged in the two red terminals for bridging. The Eq bands are all down except from 120khz-20khz are set in a frown shape. Thanks for all your help. Let me know if im forgetting any more info. Thanks.
-
4000 sqft is a pretty big space. You're driving 6 15" mains with 3k watts and you expect 2 subs with 2k watts to keep up? I think this is your first problem.
If there is an actual issue with your subs, I suspect the problem lies between the amplifier and the speakers. If you're clipping the input of the amp then it is at least getting SOME kind of signal, and a lot of it. If it's crossed over or EQ'd improperly you would hear that through the speaker.
First thing I would check is the polarity of the two subs. Not just at the terminals on the cabinet, but actually take them apart. Touch the two prongs of a 9v battery to the two speaker leads and verify that both cones move in the same direction.
-
4000 sqft is a pretty big space. You're driving 6 15" mains with 3k watts and you expect 2 subs with 2k watts to keep up? I think this is your first problem.
If there is an actual issue with your subs, I suspect the problem lies between the amplifier and the speakers. If you're clipping the input of the amp then it is at least getting SOME kind of signal, and a lot of it. If it's crossed over or EQ'd improperly you would hear that through the speaker.
First thing I would check is the polarity of the two subs. Not just at the terminals on the cabinet, but actually take them apart. Touch the two prongs of a 9v battery to the two speaker leads and verify that both cones move in the same direction.
[/quoute]
Gotcha...Yeah we were wondering if we needed more subs and power and they are like almost 100 feet away from each other. I will check the polarity tonight. Thanks for your input!!!
-
Hey...sorry so late, the amp is a Behringer EUROPOWER EP2000. The low pass filter on the mono out is activated and the filter is set at 120hertz. As our mains we have 3000 watts driving 6 15s. The church is about 4000sq feet more wider than longer and the subs are positioned standing up in the far outside corners facing straight. I dont have a SPL meter to check levels but from reading LED meters everything is pretty much at unity gain. Speakers are properly plugged in the two red terminals for bridging. The Eq bands are all down except from 120khz-20khz are set in a frown shape. Thanks for all your help. Let me know if im forgetting any more info. Thanks.
First, I don't see a switch with a 120hz low pass function on that amp. The only filter switches are for a 30 or 50hz high pass function, with a switch to bypass this function-for both input channels. Is this function actually on the mixer? Doesn't show it on the Behringer website, and can't find a manual.
Second, just because you've used the two red terminals for your speaker cable(and I'm assuming you've followed the other instructions for proper bridge function operation), doesn't mean that the cable between the subs isn't wired correctly, or as another poster pointed out, one of the drivers is mis-wired in the cabinet. IT HAPPENS, check these things out.
Third, you don't measure gain structure with an SPL meter, and how/what are you measuring with "LED meters"?
Don't use the equalizer as an active crossover. Find a real one, and set it up between 80-100hz for the low pass function, adjust gains properly, then see how it works.
Best regards,
John
-
Hey...sorry so late, the amp is a Behringer EUROPOWER EP2000. The low pass filter on the mono out is activated and the filter is set at 120hertz. As our mains we have 3000 watts driving 6 15s. The church is about 4000sq feet more wider than longer and the subs are positioned standing up in the far outside corners facing straight. I dont have a SPL meter to check levels but from reading LED meters everything is pretty much at unity gain. Speakers are properly plugged in the two red terminals for bridging. The Eq bands are all down except from 120khz-20khz are set in a frown shape. Thanks for all your help. Let me know if im forgetting any more info. Thanks.
If I understand correctly the EQ is between the mixer and the sub amp? And the EQ has all the bands below 120hz turned down? Please tell me you have the EQ on the mains if this is the curve you have set, otherwise you are removing all low frequency signal from the signal before it reaches the sub amp. Since you also had a problem getting a strong signal to a powered sub, I really suspect something other than the amp or the speakers, and IF you do have the EQ set up as you described this would cause the symptoms you are experiencing.
-
First, I don't see a switch with a 120hz low pass function on that amp. The only filter switches are for a 30 or 50hz high pass function, with a switch to bypass this function-for both input channels. Is this function actually on the mixer? Doesn't show it on the Behringer website, and can't find a manual.
Second, just because you've used the two red terminals for your speaker cable(and I'm assuming you've followed the other instructions for proper bridge function operation), doesn't mean that the cable between the subs isn't wired correctly, or as another poster pointed out, one of the drivers is mis-wired in the cabinet. IT HAPPENS, check these things out.
Third, you don't measure gain structure with an SPL meter, and how/what are you measuring with "LED meters"?
Don't use the equalizer as an active crossover. Find a real one, and set it up between 80-100hz for the low pass function, adjust gains properly, then see how it works.
Best regards,
John
Yeah...the low pass filter switch is on the mixer mono out channel. The the filter frequ selection knob is set to 120khz. On the amp there are little switches in the back that turns activates and deactivates certain functions for Channels 1 & 2 on the amp. I set it up to the manufact instructions for bridge mode. As far as testing signal I have no test equipment. I just making sure that there is proper signal to each input based on the led signal levels on each piece of equipment. On the amp I just turn it up till it starts to clip then turn it back down right under where it would start to clip.
-
Yeah...the low pass filter switch is on the mixer mono out channel. The the filter frequ selection knob is set to 120khz. On the amp there are little switches in the back that turns activates and deactivates certain functions for Channels 1 & 2 on the amp. I set it up to the manufact instructions for bridge mode. As far as testing signal I have no test equipment. I just making sure that there is proper signal to each input based on the led signal levels on each piece of equipment. On the amp I just turn it up till it starts to clip then turn it back down right under where it would start to clip.
Set the EQ to flat - or pull it out of the chain. See if that changes anything.
-
Yeah...the low pass filter switch is on the mixer mono out channel. The the filter frequ selection knob is set to 120khz. .
I assume you mean 120hz NOT 120,000 Hz. As you have stated several times.
-
If I understand correctly the EQ is between the mixer and the sub amp? And the EQ has all the bands below 120hz turned down? Please tell me you have the EQ on the mains if this is the curve you have set, otherwise you are removing all low frequency signal from the signal before it reaches the sub amp. Since you also had a problem getting a strong signal to a powered sub, I really suspect something other than the amp or the speakers, and IF you do have the EQ set up as you described this would cause the symptoms you are experiencing.
On the EQ everything ABOVE 120khz is turned down, and between 20khz-120khz its set in a frown shape with 60khz being the highest set freq on the EQ. Yeah with the powered sub...samething, you couldnt hear it at all really. You literally would have to be like 3-5feet in front of it. With the powered sub we ran it directly to the sub from the mixer because it already had a built in crossover...and it performed way better when we demo'd it at Guitar Center.
-
I assume you mean 120hz NOT 120,000 Hz. As you have stated several times.
Yes...sorry 120hz, were not up in the highs. I apologize.
-
How about trying AUX Fed subs, feed just kick drum and bass guitar and maybe keyboards. Don't put an EQ in the chain. See if that works any better.
-
How about trying AUX Fed subs, feed just kick drum and bass guitar and maybe keyboards. Don't put an EQ in the chain. See if that works any better.
You know what...I never thought about that, I did that at one other church and it worked pretty good. I will try that as well with the other suggestions im receiving. Im not sure why it was ran from the mono out anyway...Idk, not something I would have done. I also suggested that high just get a 2way crossover and run it that way, the way I consider normal, but he is stuckon controlling subs from the mixer...
-
I also suggested that high just get a 2way crossover and run it that way, the way I consider normal, but he is stuckon controlling subs from the mixer...
His opinion and stubborness, along with some questionable-appearing use EQ and signal path, will doom him to failure. He's asking for your help but refusing your advice.
Run away.
-
His opinion and stubborness, along with some questionable-appearing use EQ and signal path, will doom him to failure. He's asking for your help but refusing your advice.
Run away.
Unfortunately...that is true!!! So I just need to basically do what I know to do, and if he doesent want it that way then I cant help him. I mean...alot of times I second guess myself, or try to find ways around it. I guess this is what happens when you do.
-
On the EQ everything ABOVE 120khz is turned down, and between 20khz-120khz its set in a frown shape with 60khz being the highest set freq on the EQ. Yeah with the powered sub...samething, you couldnt hear it at all really. You literally would have to be like 3-5feet in front of it. With the powered sub we ran it directly to the sub from the mixer because it already had a built in crossover...and it performed way better when we demo'd it at Guitar Center.
You are getting your freq confused. You CONTINUALLY are putting in freq that we simply cannot hear.
It is not a matter of "being in the highs" but completely out of our hearing range.
-
You know what...I never thought about that, I did that at one other church and it worked pretty good. I will try that as well with the other suggestions im receiving. Im not sure why it was ran from the mono out anyway...Idk, not something I would have done. I also suggested that high just get a 2way crossover and run it that way, the way I consider normal, but he is stuckon controlling subs from the mixer...
Running the subs on a seperate control is very common-IF you know how to run it-And the system is setup properly.
-
Nevermind!
-
You are getting your freq confused. You CONTINUALLY are putting in freq that we simply cannot hear.
It is not a matter of "being in the highs" but completely out of our hearing range.
No...Im not getting them confused, im just typing them out wrong. Im at work as a cable installer and I deal with frequencies of different kind and decibels all day from hz to khz, to mhz to ghz. Im just multi-tasking and typing them incorrect on accident. I know 20hz isnt audible I was just stating how to EQ was set by the church. Obviously I didnt mean 20khz-120khz...but I pretty sure the get the idea when talking about low-end frequencies. Thanks alot for your input though.
-
No...Im not getting them confused, im just typing them out wrong. Im at work as a cable installer and I deal with frequencies of different kind and decibels all day from hz to khz, to mhz to ghz. Im just multi-tasking and typing them incorrect on accident. I know 20hz isnt audible I was just stating how to EQ was set by the church. Obviously I didnt mean 20khz-120khz...but I pretty sure the get the idea when talking about low-end frequencies. Thanks alot for your input though.
I will be happy to come out and check everything. I bill at 120 k$ per hour, if that is ok.
-
I will be happy to come out and check everything. I bill at 120 k$ per hour, if that is ok.
Lol...Im not sure, but I think I can hire and fly someone in for just a little less....Ok much less!!!
-
I will be happy to come out and check everything. I bill at 120 k$ per hour, if that is ok.
$120,000 per hour seems a bit steep, even though you might be quite good at what you do.
;-)
-
Obviously I didnt mean 20khz-120khz...but I pretty sure the get the idea when talking about low-end frequencies. Thanks alot for your input though.
Numbers mean a lot in this business. The only way for us to "get the idea" is for you to enter them correctly.
-
Number mean a lot in this business. The only way for us to "get the idea" is for you to enter them correctly.
8)
-
$120,000 per hour seems a bit steep, even though you might be quite good at what you do.
;-)
*co-sign
-
I guess that misplaced k does mean something significant.
-
I guess that misplaced k does mean something significant.
I think they're called "orders of magnitude" ;)
-
I guess that misplaced k does mean something significant.
If you think of it in terms of dB-that would be a 30dB difference.
To some people- that makes a difference HA-HA
-
Hold on...I think im having a retard moment, just thought about something. Even though its in bridge mode shouldnt there be to channel 1 AND 2 on the amp. Right know its mono from the mixer to one channel on EQ to ONLY ONE channel on the amp. So if were both positive terminals on each side of the amp, it would only make sense that both sides have signal??? Am I wrong with this theory??
-
Hold on...I think im having a retard moment, just thought about something. Even though its in bridge mode shouldnt there be to channel 1 AND 2 on the amp. Right know its mono from the mixer to one channel on EQ to ONLY ONE channel on the amp. So if were both positive terminals on each side of the amp, it would only make sense that both sides have signal??? Am I wrong with this theory??
In Bridge Mode, only Ch 1 control is operative.
If you are unclear about this, read pages 7-8 of the manual. Be sure to turn down the gain on Ch 2, per the manual.
http://www.behringer.com/assets/EP2000_P0A38_M_EN.pdf
-
If you think of it in terms of dB-that would be a 30dB difference.
To some people- that makes a difference HA-HA
So should I get a 2000 watt amp or a 2200 watt amp?
It has 200 more watts....
;-)
-
[quote He is using the mono out on the board to send signal, the line has a female to female adapter in it to extend it.
[/quote]
This caught my attention - make sure the adapter is not a transformer. I've seen this!
-
make sure the adapter is not a transformer. I've seen this!
I have not seen a transformer adapter in a F-F tube, they would be in a F-M tube. The only problem with having a transformer in line would be if it is a cheesy little transformer that saturates at a relatively low level with sub frequencies.
Mac
-
I have not seen a transformer adapter in a F-F tube, they would be in a F-M tube. The only problem with having a transformer in line would be if it is a cheesy little transformer that saturates at a relatively low level with sub frequencies.
Mac
And even at full range freq.
i remember the first time I ran into this. There was this "weird sound" coming through a friends system. Not really "distorted (clipped)", but it sounded compressed (back when compressors weren't common at the club level and a bit "fuzzy"-but not bad.
They were using it to send an unbalanced signal down the snake (converting to balanced) and then to the amp.
When I replaced it with a much larger transformer-the signal really cleaned up and had much more dynamic range.
-
On the EQ everything ABOVE 120khz is turned down, and between 20khz-120khz its set in a frown shape with 60khz being the highest set freq on the EQ...
How do you have 'every thing above 120 'turned down' and from 120-20 'set in a frown shape'. This is contradictory. THose frequencies are either turned down or they are a frown, they can't be both.
As others have said, cable around the EQ (physically bypass it) and try again.
-
On the EQ everything ABOVE 120khz is turned down, and between 20khz-120khz its set in a frown shape with 60khz being the highest set freq on the EQ. Yeah with the powered sub...samething, you couldnt hear it at all really. You literally would have to be like 3-5feet in front of it. With the powered sub we ran it directly to the sub from the mixer because it already had a built in crossover...and it performed way better when we demo'd it at Guitar Center.
If you're getting the exact same results from the powered sub, (again, not really sure w/o knowing model and wattage etc. ) you might want to check the output at the mono out on the board. I'd be suspect of the B....r board. Are there any selectors for the mono out signal?
If you're by-passing the EQ , amp, cables, and speakers, and still way low output, consider hooking up the subs to another output, even if a temp test. See if you get any better levels from an aux out or such, just as a test. Even running a full range signal into the EQ/amp/speakers setup might give you an idea if the mono out is bad.
-
As you can see, I am new to this forum, so do not know if it is possible to post photos, but a picture is worth 1000 words. Any chance of taking photos of the EQ, board and amp settings? It would make things so much clearer.
Terry
-
Start with basics....
Just the mixer, one amp/channel, and one top running full range. Make sure this works FIRST.
Then add the other top (no cross over, no eq, just mixer->amps->speakers).
Then, put the cross-over in and use the LF amp in normal (not briged) mode into only 1 sub and the HF amp into one top.
Hopefully somewhere along this path you will find something that isn't working right and report it ;)
As an aside, those subs aren't going to put out much of anything even when working properly.