Powered speaker setup, all platforms, but especially PX/DRPA
In this post we’ll go through a few setups for Active systems. This will apply to the Driverack PX, DRPA 240, 260, 400 and 4000 series processors, however some reference to specific platforms my apply and be noted due to limitations of some of the processors.
First a couple acronyms to clear up
HPF…this is the LOWEST point you want your speakers to reproduce!
LPF …this is the HIGHEST point you want your speaker to reproduce!
SLOPE. How quickly we want the frequencies to fall off at the xover point.
LR, BW, BS the different filter types that the xovers emulate
6,8,12,24,36,48 the steepness of the slope the crossover possesses, the higher the number the steeper the slope but the more complex the filter and the more anomalies that are present in the filter, but generally the less interaction between the xover points.
Generally when we speak of providing processing for an active system we aren’t specifically speaking of ‘crossovers’, but’ band pass filters’. It’s really just a matter of semantics since the ‘filters’ on the PX resemble the xovers (crossovers) in all other platforms, and all platforms listed can provide band pass filters as well. If you have an active setup and no subs and you set a crossover in the PX, DRPA, 260..etc, that has a BW 18 slope @ 50 hz HPF and set to out (allow the speakers to determine how high they can reproduce and not attempt to limit that with a lopass filter)or some other LPF frequency cutoff, you have technically provided a “bandpass filter�. Bandpass filters have slopes and filter types just like xovers.
If you are going to be using only fullrange speakers and no subs, select preset/program 3 and load it. Press the xover button, Using the Prev< and next> buttons and the Data wheel, select the HPF and set a frequency equal to the LF frequency response of the speakers (or lower or higher depending on application) I recommend a BW18 filter. There isn't an LPF on the HI outs. Then simply plug the speakers into the HI outs and your ready for the other features. Remember to store any changes or they will be lost when you turn the unit off. Save process is below...
The xover point is primarily determined by top speaker configuration. Generally we look at the 3 db down point the speaker can produce and the power available, and woofer size as the determining points. The other factor that figures in here is subwoofer type and frequency capability. Some subs can reproduce up to 300 hz (and even higher), these are typically the front loaded vented subs. The problem here becomes that as we get over 120 hz the subs start producing intelligible sound. This ends up sounding honky and nasally in subs. Horn loaded and other subs where the speaker is deep inside the cabinet will generally reproduce LESS than 120hz. So the smaller the woofer in the tops the less low frequency information they are generally capable of reproducing, and the lower the xover point, the less clear the midrange voice will be as well. With a 12� speaker I generally suggest a 120 hz area xover, 10� slightly higher but depending on the power available and the speakers capability, perhaps 120hz would work better (note some multiple driver units and those with specially designed horn loaded low end can sustain lower xover points) , but generally when using 10� woofers and up, a low mid cab would be in order. Even if you have 15� 2 ways with 150 watts, even though the MFG says they will reproduce 50 hz doesn’t mean they should be allowed to. A more appropriate xover in this case might be 120 hz due to the limited power, and subsequent light weight woofer construction. Therefore speakers like the SRM 450 with plenty of power and a good woofer and cabinet design could be crossed as low as 65-70 hz, but again with some compromise to the upper mid sound of the speaker. This is due to the larger excursion of the low frequencies and the cone breakup because of it. We are far better off crossing at around 100 hz since our upper mids will be cleaner and the tops will have more power to get louder with less distortion.
Note: Size of driver doesn’t determine the low frequency cutoff! That may seem counter intuitive but know this, a 6� or even 8� speaker reacts quicker (mass) and can reproduce lower frequencies with less distortion than the larger speakers,(think Ferrari engine in a dump truck (18�) and Ferrari engine in a well… Ferrari… which will start and stop faster?) they are usually limited by the motor structure and cross section of the driver. So a LABsub with 2 each 12� woofers will go lower and get louder than 4 bass reflex (front loaded) 18� speakers when horn loaded, and have FAR less distortion as well..
Now assuming you have a pair of SRM 450 speakers and a single, or pair of powered SRS1500 subs (as was recently posted), select the wizard by pressing the front panel button. Answer the questions for stereo (linked... not dual mono, unless you want to do every task twice) 2x3 or 2x4 setup using all custom entries. This will allow for one output for each speaker (or a mono out to the subs that can be daisy chained). (You could select the Mackie presets 300 and NONE but they are essentially the same, just blank bandpass filters)
*******************************NOTE***********************************
At this point it doesn’t matter if were using Mackie, JBL, Celestion, Yorkville, or EAW speakers, whatever the brand it doesn’t matter, this preset will work for ALL powered speaker combinations even if they’re mix and matched tops and subs! Just remember to consider the size of the woofer in the top cab and the power available!
***********************************************************************
Once you have answered all the questions and created your preset, hit the Program button. This will load the preset we are building. Now hit the XOVER button. Using the data wheel and <prev, next> PG buttons select the LO outs xover, for the HPF set it @ BW18 @ 30hz. (this will allow the powered sub to set it’s own HPFunless it is capable of sub 30 hz performance, then if you want set it lower, but know this, the lower the frequency the more power it takes to reproduce those frequencies) Next, select the LPF and set it @ 96.4 hz LR24hz. A brief note about the crossovers we select.(on the 240, 260 and 400-4000 series this is much easier with the GUI or in the case of the 4000 series, HiQ net) We usually spec a BW 18 frequency for the subs HPF and LR 24 filters for the other xovers. This is because we know the propagation delay of the LR24 filter(about 8 ms), and a majority of the speaker manufacturers also spec those filters. For this exercise we will focus on the PX and DRPA applications.
Now select the HI (the hi outs on the DRPA have three PEQ’s and NO LPF) outs xover and set the HPF @ 102.1 hz @ LR24 since there is no LPF on the hi outs, if you want one then you will need to use the MID outs, but you trade that for one of the PEQ’s as the mid outs have only two.
Now hook up the SRM450’s to the HI outs, subs will be hooked to the LO outs. For 2x3 setups you run out of the Left mono out, and daisy chain if there is more than one sub. For stereo 2x4 setups use the left and right LOW outs.
What you have then is 3 or 4 bandpass filters that allow the SRM 450's to get from 102.1hz on up, and the LOW outs to get from 96.4 hz down. The reason for the split is that we can minimize the xover interaction that way.
Now do a gain structure... with powered speakers it can be challenging, but start the SRM 450's @ 12oclock on the gain control, crank the sub frequency control all the way UP.(this will allow the Driverack to set the xover frequency) Play some good full range music through the system and balance the sub output with the tops using the gain control on the subs.(our Driverack crossover gains are still @ -0- db…no cut or gain applied) If you can't get the subs loud enough with the gain control, turn the SRM's down a little and try again. (it isn’t a problem if you find you need to use the xover gain controls for this either, sometimes we need to) Once you get that done, do a gain structure as per the read me first section with the speakers unplugged. This will make sure everything pre speakers is talking the same language. Plug the speakers back in and see if you can determine a clip point for the speakers ( that point at which the clip lights just start to winkle.. on any of the speakers, it doesn't matter which starts first). Mark the mixer or put this point in your head as the max the faders will ever be allowed to go ( and slightly less would be better). You can set the limiter up at this point to keep the system from getting to that point...
NOTE that powered speakers HAVE limiters, and if you see the limit light that’s TOO DARN HIGH... you will have trouble if you continue @ that level... (read that REPLACE cones, drivers…) Note: when you let the smoke out… it’s REALLY REALLY hard to get it back in!
For those that have more than 2 tops, you could put one set on the HI outs and one on the MID outs. This would allow you to POWER SHADE (one set on the inside for close up front and one set louder for outside fills… etc) or one set could be set up as delay towers (this would require the DR240 and above since the PX and DRPA don’t have enough delay available to do this) for covering larger crowds. To do this…select the MID outs xover and set the HPF at 102.1 hz @ LR24 (again this is driver /power dependent, and this is again a hypothetical setup.. your mileage may vary...) then calculate/measure the distance to the delay towers. Set the delay using the post crossover delay in the case of systems with 2 in and running stereo, and either pre or post xover delay on 4 in processors. On the Driverack 200 series and above the delay is re-allocatable in the \"Config\" mode within the maximum delay available on a given platform. In the 260 that is 2.7 seconds total delay (over 1/2 mile), the 4800 has 1365 ms on the outputs and 682 ms on the inputs...or 1.813 miles total...
Remember that if you have more than 2 tops that you don’t want the coverage patterns
to overlap. This will cause comb filtering and limit the intelligibility of the system. Find out what the coverage pattern is and splay the speakers to avoid interaction. If you need to cover the same area with both sets, and it’s possible to stack the speakers, put the horns together. That means place the top speaker UPSIDE DOWN. This will allow the horns to couple, and prevent comb filtering of the intelligible frequencies. Make sure though that the speakers are securely tied together so they don’t fall.
Next, if you wish to auto EQ the system I recommend doing so outdoors, or using the “New indoor method� one side only, and since the subs are best eq’ed by ear my recommendation would be to do tops only, but all that and more is in the other parts of this “Read me first� section
Now all that remains is to STORE the preset. Remember that you will loose all changes if you do not. It takes 3 presses of the STORE button to save a preset. You will be asked where you want the preset to be located (preset #), to NAME the preset (you can name it here) and are you sure you want to replace preset #....
Have fun… rock on!
First a couple acronyms to clear up
HPF…this is the LOWEST point you want your speakers to reproduce!
LPF …this is the HIGHEST point you want your speaker to reproduce!
SLOPE. How quickly we want the frequencies to fall off at the xover point.
LR, BW, BS the different filter types that the xovers emulate
6,8,12,24,36,48 the steepness of the slope the crossover possesses, the higher the number the steeper the slope but the more complex the filter and the more anomalies that are present in the filter, but generally the less interaction between the xover points.
Generally when we speak of providing processing for an active system we aren’t specifically speaking of ‘crossovers’, but’ band pass filters’. It’s really just a matter of semantics since the ‘filters’ on the PX resemble the xovers (crossovers) in all other platforms, and all platforms listed can provide band pass filters as well. If you have an active setup and no subs and you set a crossover in the PX, DRPA, 260..etc, that has a BW 18 slope @ 50 hz HPF and set to out (allow the speakers to determine how high they can reproduce and not attempt to limit that with a lopass filter)or some other LPF frequency cutoff, you have technically provided a “bandpass filter�. Bandpass filters have slopes and filter types just like xovers.
If you are going to be using only fullrange speakers and no subs, select preset/program 3 and load it. Press the xover button, Using the Prev< and next> buttons and the Data wheel, select the HPF and set a frequency equal to the LF frequency response of the speakers (or lower or higher depending on application) I recommend a BW18 filter. There isn't an LPF on the HI outs. Then simply plug the speakers into the HI outs and your ready for the other features. Remember to store any changes or they will be lost when you turn the unit off. Save process is below...
The xover point is primarily determined by top speaker configuration. Generally we look at the 3 db down point the speaker can produce and the power available, and woofer size as the determining points. The other factor that figures in here is subwoofer type and frequency capability. Some subs can reproduce up to 300 hz (and even higher), these are typically the front loaded vented subs. The problem here becomes that as we get over 120 hz the subs start producing intelligible sound. This ends up sounding honky and nasally in subs. Horn loaded and other subs where the speaker is deep inside the cabinet will generally reproduce LESS than 120hz. So the smaller the woofer in the tops the less low frequency information they are generally capable of reproducing, and the lower the xover point, the less clear the midrange voice will be as well. With a 12� speaker I generally suggest a 120 hz area xover, 10� slightly higher but depending on the power available and the speakers capability, perhaps 120hz would work better (note some multiple driver units and those with specially designed horn loaded low end can sustain lower xover points) , but generally when using 10� woofers and up, a low mid cab would be in order. Even if you have 15� 2 ways with 150 watts, even though the MFG says they will reproduce 50 hz doesn’t mean they should be allowed to. A more appropriate xover in this case might be 120 hz due to the limited power, and subsequent light weight woofer construction. Therefore speakers like the SRM 450 with plenty of power and a good woofer and cabinet design could be crossed as low as 65-70 hz, but again with some compromise to the upper mid sound of the speaker. This is due to the larger excursion of the low frequencies and the cone breakup because of it. We are far better off crossing at around 100 hz since our upper mids will be cleaner and the tops will have more power to get louder with less distortion.
Note: Size of driver doesn’t determine the low frequency cutoff! That may seem counter intuitive but know this, a 6� or even 8� speaker reacts quicker (mass) and can reproduce lower frequencies with less distortion than the larger speakers,(think Ferrari engine in a dump truck (18�) and Ferrari engine in a well… Ferrari… which will start and stop faster?) they are usually limited by the motor structure and cross section of the driver. So a LABsub with 2 each 12� woofers will go lower and get louder than 4 bass reflex (front loaded) 18� speakers when horn loaded, and have FAR less distortion as well..
Now assuming you have a pair of SRM 450 speakers and a single, or pair of powered SRS1500 subs (as was recently posted), select the wizard by pressing the front panel button. Answer the questions for stereo (linked... not dual mono, unless you want to do every task twice) 2x3 or 2x4 setup using all custom entries. This will allow for one output for each speaker (or a mono out to the subs that can be daisy chained). (You could select the Mackie presets 300 and NONE but they are essentially the same, just blank bandpass filters)
*******************************NOTE***********************************
At this point it doesn’t matter if were using Mackie, JBL, Celestion, Yorkville, or EAW speakers, whatever the brand it doesn’t matter, this preset will work for ALL powered speaker combinations even if they’re mix and matched tops and subs! Just remember to consider the size of the woofer in the top cab and the power available!
***********************************************************************
Once you have answered all the questions and created your preset, hit the Program button. This will load the preset we are building. Now hit the XOVER button. Using the data wheel and <prev, next> PG buttons select the LO outs xover, for the HPF set it @ BW18 @ 30hz. (this will allow the powered sub to set it’s own HPFunless it is capable of sub 30 hz performance, then if you want set it lower, but know this, the lower the frequency the more power it takes to reproduce those frequencies) Next, select the LPF and set it @ 96.4 hz LR24hz. A brief note about the crossovers we select.(on the 240, 260 and 400-4000 series this is much easier with the GUI or in the case of the 4000 series, HiQ net) We usually spec a BW 18 frequency for the subs HPF and LR 24 filters for the other xovers. This is because we know the propagation delay of the LR24 filter(about 8 ms), and a majority of the speaker manufacturers also spec those filters. For this exercise we will focus on the PX and DRPA applications.
Now select the HI (the hi outs on the DRPA have three PEQ’s and NO LPF) outs xover and set the HPF @ 102.1 hz @ LR24 since there is no LPF on the hi outs, if you want one then you will need to use the MID outs, but you trade that for one of the PEQ’s as the mid outs have only two.
Now hook up the SRM450’s to the HI outs, subs will be hooked to the LO outs. For 2x3 setups you run out of the Left mono out, and daisy chain if there is more than one sub. For stereo 2x4 setups use the left and right LOW outs.
What you have then is 3 or 4 bandpass filters that allow the SRM 450's to get from 102.1hz on up, and the LOW outs to get from 96.4 hz down. The reason for the split is that we can minimize the xover interaction that way.
Now do a gain structure... with powered speakers it can be challenging, but start the SRM 450's @ 12oclock on the gain control, crank the sub frequency control all the way UP.(this will allow the Driverack to set the xover frequency) Play some good full range music through the system and balance the sub output with the tops using the gain control on the subs.(our Driverack crossover gains are still @ -0- db…no cut or gain applied) If you can't get the subs loud enough with the gain control, turn the SRM's down a little and try again. (it isn’t a problem if you find you need to use the xover gain controls for this either, sometimes we need to) Once you get that done, do a gain structure as per the read me first section with the speakers unplugged. This will make sure everything pre speakers is talking the same language. Plug the speakers back in and see if you can determine a clip point for the speakers ( that point at which the clip lights just start to winkle.. on any of the speakers, it doesn't matter which starts first). Mark the mixer or put this point in your head as the max the faders will ever be allowed to go ( and slightly less would be better). You can set the limiter up at this point to keep the system from getting to that point...
NOTE that powered speakers HAVE limiters, and if you see the limit light that’s TOO DARN HIGH... you will have trouble if you continue @ that level... (read that REPLACE cones, drivers…) Note: when you let the smoke out… it’s REALLY REALLY hard to get it back in!
For those that have more than 2 tops, you could put one set on the HI outs and one on the MID outs. This would allow you to POWER SHADE (one set on the inside for close up front and one set louder for outside fills… etc) or one set could be set up as delay towers (this would require the DR240 and above since the PX and DRPA don’t have enough delay available to do this) for covering larger crowds. To do this…select the MID outs xover and set the HPF at 102.1 hz @ LR24 (again this is driver /power dependent, and this is again a hypothetical setup.. your mileage may vary...) then calculate/measure the distance to the delay towers. Set the delay using the post crossover delay in the case of systems with 2 in and running stereo, and either pre or post xover delay on 4 in processors. On the Driverack 200 series and above the delay is re-allocatable in the \"Config\" mode within the maximum delay available on a given platform. In the 260 that is 2.7 seconds total delay (over 1/2 mile), the 4800 has 1365 ms on the outputs and 682 ms on the inputs...or 1.813 miles total...
Remember that if you have more than 2 tops that you don’t want the coverage patterns
to overlap. This will cause comb filtering and limit the intelligibility of the system. Find out what the coverage pattern is and splay the speakers to avoid interaction. If you need to cover the same area with both sets, and it’s possible to stack the speakers, put the horns together. That means place the top speaker UPSIDE DOWN. This will allow the horns to couple, and prevent comb filtering of the intelligible frequencies. Make sure though that the speakers are securely tied together so they don’t fall.
Next, if you wish to auto EQ the system I recommend doing so outdoors, or using the “New indoor method� one side only, and since the subs are best eq’ed by ear my recommendation would be to do tops only, but all that and more is in the other parts of this “Read me first� section
Now all that remains is to STORE the preset. Remember that you will loose all changes if you do not. It takes 3 presses of the STORE button to save a preset. You will be asked where you want the preset to be located (preset #), to NAME the preset (you can name it here) and are you sure you want to replace preset #....
Have fun… rock on!
0