So I'm setting up a PA system and I'm kind of confused. I have a berhinger europower p1500 amp. This amp is to be bridged to my subwoofer, a behringer e1800x. I'm imagining this is a very simple answer but it still is confusing me. To go from the amp to the speaker am I required to have a balanced (trs) cable? I have the speakon for the amp wired to +1/+2 but then to go into my mixer I require a 1/4" connector. if i am using a TS cable would that not be putting power to the + terminal (tip of the TS cable) and then also power to the - sleeve which is the ground? isn't that a textbook short circuit? does it work like this or am i required to have a balanced TRS cable? I am very confused.
Also, once it goes from amp to mixer to speaker does the speaker end also need to be wired +1/+2 or does it stay +1/-1?
thanks so much for any help.
Also, once it goes from amp to mixer to speaker does the speaker end also need to be wired +1/+2 or does it stay +1/-1?
thanks so much for any help.
Download the user manual. It explains this connection. In fact the information you need is printed on the rear panel of the amp. The input jacks have nothing to do with the speaker connections.
You do not "put power to" the input jacks. If you plug a TS cord into a TRS jacks, yes it grounds one side of the balanced line. But it is not a dead short as there are resistors in the lines.
You do not "put power to" the input jacks. If you plug a TS cord into a TRS jacks, yes it grounds one side of the balanced line. But it is not a dead short as there are resistors in the lines.
well uncertain why it's confusing...input and output of the amp are entirely different...so thinking there's a short somehow is not correct.
i think the logical flaw is that in bridge mode channel 2 is in fact the "negative" half of a now "single" amp. ( take a moment to look at the labeling on the amp for bridge mode you should notice that channel 2 is - )
i think the logical flaw is that in bridge mode channel 2 is in fact the "negative" half of a now "single" amp. ( take a moment to look at the labeling on the amp for bridge mode you should notice that channel 2 is - )
For Bridged operation the speaker cable must be wired 1+/2+ at the amplifier end and 1+/1- at the speaker end. This means the cable cannot be reversed so you need to mark the amp end with some colored tape or something.
What mixer do you have?
Johnnie:
You are confusing inputs with outputs & yes there are Speakons which accept Jacks.
My QSC GX amps use them and mine are dark green. Prior Speakons there were old speakers made with jack inputs. I remember Community / Dynacord speakers.
Mixer / source goes Left. Speakers go right. Period !!
TS or TRS doesn't matter. Your amp accepts both and it is related to cable length / noise attenuation needed etc. Use TRS if posssible.
Bear in mind if two or more amp inputs are daisy chained connected together like in a line array and one of the cable is TS, all the amp inputs will become unbalanced. TIP is to use different colors for cables.
Speakons never go into mixer inputs, unless in an obscure emergency situation and heavily attenuated, but I've seen all...
A friend of mine connected a speakon cable between two amp outputs and blew both.
DON'T DO IT. Something will surely explode !!
Your amp provides both channels on Output 1 Speakon. This comes in handy if You have a cab with two speakers You can use one cable with 4 wires for connecting both.
Standard wiring per channel is 1+ 1- for stereo or parallel but 1+ 2+ for bridge operation, because You need to tap into the other channel.
I'm not going to discuss the one or more speaker per channel dilemma, since it all depends on maintaining the minimum load to the amp's channel. When I say speaker, I mean one or more speakers for that rated minimum impedance connected in series / parallel combinations. Let's assume only one speaker per channel for making it simple.
First: Don't confuse parallel wiring with parallel amp operation.
Stereo mode:
You take L & R from the mixer and feed them each to each amp's channels. Meant for 2 speakers connected, both in phase. 2 Gain Knobs to fiddle.
Imagine one amp at the middle of the stage, 1 speaker at each side.
Parallel mode:
You take L or R or the sum of the two from the mixer and feed them into channel 1 only and then it is internally feed to the other channel in phase. Both channels play the same program and it is also meant for 2 speakers connected. 2x mono & also 2 knobs to fiddle.
Imagine one amp and 2 speakers at each side of the room. One amp for L, one amp for R.
Think of line arrays were the amps on each side of the stage are paralleled.
You can also achieve the same, leaving it in stereo mode and feed XLR input 1 IN, take out form Channel 1 Jack and feed it to XLR Input 2 or Jack 2 Input, as the XLRs and Jacks are usually wired in parallel.
Bridge mode:
You take L or R or the sum of the two from the mixer and feed them to channel 1 only, and take the output from the bridge of the two. Channel 2 is not used the regular way, since it is internally "hijacked and switched" for the negative part of the bridge operation. In bridge mode, basically You are inverting one of the channels inside the amp. Now You use only one gain knob which controls both channels. The other knob doesn't do anything.
Your assumption is somewhat correct, but bear in mind You also would "Theoretically quadruple" the power this way. Bridge is meant for connecting one speaker only. Each bridge part must see the minimum impedance of each channel (2 Ohm), so You actually double the power, unless we are talking about heavy duty tour amps with beefier supplies and massive cooling designed for it.
Think One amp for two tops & one amp for the double power sub.
In order to sum to mono from the mixer. You can use resistors like RANE.
This tip came form another board, but i have lost the link to it.
Feed the non-inverting output from one channel and the inverting output from the other channel to same XLR or jack input. I've tried and doesn't attenuate the signal, but it is a two to one unidirectional cable. It doesn't work backwards. I use it many times.
TIP Left to to XLR Pin 2. (or XLR Left 2 to 2)
Ring Right to XLR pin 3. (or XLR Right 3 to 3)
Ground to pin 1.
This works only if Your mixer has true balanced outputs, so signal on XLR pin 3 or jack ring.
Many cheap mixers offer cheated balanced outputs which short pin 3 or jack ring to ground.
How to tell:
Connect a headphone to the line out jacks. You should hear a out of phase signal on both channels. For XLRs test between pins 1-2 & 1-3
Behringer usually has SUB outs on their gear which You can use.
Some folks recommend the use of three wire cable for speakers, You would wire also the 2+ Speakon terminal, but this would need also to be done inside the speaker. ... but in amps like these You short amp outputs, unless You install a switch inside the speaker for selecting between normal & bridge
I recommend and I use a simple short male to female adapter cable for bridge operation, which goes between the bridged amp and the speaker cable. when needed.
Bridged and paralleled amplifiers - Wikipedia
Bridging Adapter For Power Amps
RANE Commercial - Knowledge Base
https://www.google.com/url?sa=t&rct...3z_4L-boJ0uGLntACn6Mjj&cshid=1621648142885818
You are confusing inputs with outputs & yes there are Speakons which accept Jacks.
My QSC GX amps use them and mine are dark green. Prior Speakons there were old speakers made with jack inputs. I remember Community / Dynacord speakers.
Mixer / source goes Left. Speakers go right. Period !!
TS or TRS doesn't matter. Your amp accepts both and it is related to cable length / noise attenuation needed etc. Use TRS if posssible.
Bear in mind if two or more amp inputs are daisy chained connected together like in a line array and one of the cable is TS, all the amp inputs will become unbalanced. TIP is to use different colors for cables.
Speakons never go into mixer inputs, unless in an obscure emergency situation and heavily attenuated, but I've seen all...
A friend of mine connected a speakon cable between two amp outputs and blew both.
DON'T DO IT. Something will surely explode !!
Your amp provides both channels on Output 1 Speakon. This comes in handy if You have a cab with two speakers You can use one cable with 4 wires for connecting both.
Standard wiring per channel is 1+ 1- for stereo or parallel but 1+ 2+ for bridge operation, because You need to tap into the other channel.
I'm not going to discuss the one or more speaker per channel dilemma, since it all depends on maintaining the minimum load to the amp's channel. When I say speaker, I mean one or more speakers for that rated minimum impedance connected in series / parallel combinations. Let's assume only one speaker per channel for making it simple.
First: Don't confuse parallel wiring with parallel amp operation.
Stereo mode:
You take L & R from the mixer and feed them each to each amp's channels. Meant for 2 speakers connected, both in phase. 2 Gain Knobs to fiddle.
Imagine one amp at the middle of the stage, 1 speaker at each side.
Parallel mode:
You take L or R or the sum of the two from the mixer and feed them into channel 1 only and then it is internally feed to the other channel in phase. Both channels play the same program and it is also meant for 2 speakers connected. 2x mono & also 2 knobs to fiddle.
Imagine one amp and 2 speakers at each side of the room. One amp for L, one amp for R.
Think of line arrays were the amps on each side of the stage are paralleled.
You can also achieve the same, leaving it in stereo mode and feed XLR input 1 IN, take out form Channel 1 Jack and feed it to XLR Input 2 or Jack 2 Input, as the XLRs and Jacks are usually wired in parallel.
Bridge mode:
You take L or R or the sum of the two from the mixer and feed them to channel 1 only, and take the output from the bridge of the two. Channel 2 is not used the regular way, since it is internally "hijacked and switched" for the negative part of the bridge operation. In bridge mode, basically You are inverting one of the channels inside the amp. Now You use only one gain knob which controls both channels. The other knob doesn't do anything.
Your assumption is somewhat correct, but bear in mind You also would "Theoretically quadruple" the power this way. Bridge is meant for connecting one speaker only. Each bridge part must see the minimum impedance of each channel (2 Ohm), so You actually double the power, unless we are talking about heavy duty tour amps with beefier supplies and massive cooling designed for it.
Think One amp for two tops & one amp for the double power sub.
In order to sum to mono from the mixer. You can use resistors like RANE.
This tip came form another board, but i have lost the link to it.
Feed the non-inverting output from one channel and the inverting output from the other channel to same XLR or jack input. I've tried and doesn't attenuate the signal, but it is a two to one unidirectional cable. It doesn't work backwards. I use it many times.
TIP Left to to XLR Pin 2. (or XLR Left 2 to 2)
Ring Right to XLR pin 3. (or XLR Right 3 to 3)
Ground to pin 1.
This works only if Your mixer has true balanced outputs, so signal on XLR pin 3 or jack ring.
Many cheap mixers offer cheated balanced outputs which short pin 3 or jack ring to ground.
How to tell:
Connect a headphone to the line out jacks. You should hear a out of phase signal on both channels. For XLRs test between pins 1-2 & 1-3
Behringer usually has SUB outs on their gear which You can use.
Some folks recommend the use of three wire cable for speakers, You would wire also the 2+ Speakon terminal, but this would need also to be done inside the speaker. ... but in amps like these You short amp outputs, unless You install a switch inside the speaker for selecting between normal & bridge
I recommend and I use a simple short male to female adapter cable for bridge operation, which goes between the bridged amp and the speaker cable. when needed.
Bridged and paralleled amplifiers - Wikipedia
Bridging Adapter For Power Amps
RANE Commercial - Knowledge Base
https://www.google.com/url?sa=t&rct...3z_4L-boJ0uGLntACn6Mjj&cshid=1621648142885818
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thanks!
thanks everyone for the help! I am now (like almost everyone new) confused about the rms vs program. I'm finding conflicting sources telling me to focus on rms, others to say program. I am not new to rms ratings as I come from home theatre so this makes sense to me. what i don't understand is some people saying to have your amp able to produce double the rms wattage, which would be the program? so an amp that does 400w should be matched up with a 400w program speaker? or do i want an amp that can do 800w matched to a 400w program?
ie. My amp is a crown xls 602 which does 380w into 8ohms and my sub is a behringer e1800x which does 400w program. do i match this to it or do i want to bridge my behringer ep1500 which would do 800w at 8 ohm?
I understand i want headroom, i just don't understand if that is incorporated in the program being double the rms or if i need headroom above the program.
thanks!
thanks everyone for the help! I am now (like almost everyone new) confused about the rms vs program. I'm finding conflicting sources telling me to focus on rms, others to say program. I am not new to rms ratings as I come from home theatre so this makes sense to me. what i don't understand is some people saying to have your amp able to produce double the rms wattage, which would be the program? so an amp that does 400w should be matched up with a 400w program speaker? or do i want an amp that can do 800w matched to a 400w program?
ie. My amp is a crown xls 602 which does 380w into 8ohms and my sub is a behringer e1800x which does 400w program. do i match this to it or do i want to bridge my behringer ep1500 which would do 800w at 8 ohm?
I understand i want headroom, i just don't understand if that is incorporated in the program being double the rms or if i need headroom above the program.
thanks!
If you want or need the absolute maximum output from the speaker then more headroom is good, but with more amp power available the driver is at higher risk of damage from over excursion or overheating so more protection is required. Also consider... there is only a 3dB difference in SPL between RMS and Program which isn't very much... it might just be preceptable so sometimes the risk isn't justified, but on the other hand that extra 3dB might just be enough to allow for clean dynamics at high output, and if the sub driver can handle those peaks cleanly it's all good. The music genres you like also factors into this decision, genres that are quite dynamic require more amp headroom but are thermally easier on the drivers, genres with sustained bass tones will stress sub drivers harder so in this case amp power should be limited to about the RMS rating.
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Some folks tell the amp should have double the power in order never to clip, since clipping is what kills tweeters. First ones to blow in the chain. That also means operating the amp cooler at half power -3dB point.
But my experience tells me if You have more power You will actually using it when You are excited with the crowd, and of course the speakers can't handle that much. Some Dj's use that technique of raising with the beat in order to motivate the crowd. Your Mic Level will be also louder than the music when You scream.
If You drive a sports car, You will be throttling the gas pedal, won't You ?
If You bring Your main faders to 0 dB Vu on the mixing desk and calibrate amp gain for the -3dB point and never exceed that 0 dB on the desk, except for a few seconds when mixing, You should be fine.
When You mix two signals the overall main levels raise You know. If You have PFL with VU monitoring facility, use it to adjust the channel gain before raising the fader into the mix.
You can always put another similar speaker in series for protection, since both will handle the full amp's power unless.. and believe me You will clip it when excited..
The use of a compressor can be handy in these situations. All Concert technicians use them specially for mics & drums at the monitoring stage.
Learn about Gain structure calibration. The technicians on the monitoring stage far away from the main stage know if their amp stacks are clipping or not by looking at the Vu's on the main mixing desk. They can't see the tiny clip led's on the stage amps.
But my experience tells me if You have more power You will actually using it when You are excited with the crowd, and of course the speakers can't handle that much. Some Dj's use that technique of raising with the beat in order to motivate the crowd. Your Mic Level will be also louder than the music when You scream.
If You drive a sports car, You will be throttling the gas pedal, won't You ?
If You bring Your main faders to 0 dB Vu on the mixing desk and calibrate amp gain for the -3dB point and never exceed that 0 dB on the desk, except for a few seconds when mixing, You should be fine.
When You mix two signals the overall main levels raise You know. If You have PFL with VU monitoring facility, use it to adjust the channel gain before raising the fader into the mix.
You can always put another similar speaker in series for protection, since both will handle the full amp's power unless.. and believe me You will clip it when excited..
The use of a compressor can be handy in these situations. All Concert technicians use them specially for mics & drums at the monitoring stage.
Learn about Gain structure calibration. The technicians on the monitoring stage far away from the main stage know if their amp stacks are clipping or not by looking at the Vu's on the main mixing desk. They can't see the tiny clip led's on the stage amps.
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