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Title: Best way to configure XTI6002
Post by: Debbie Dunkley on April 21, 2014, 10:29:40 PM
I know this is probably basic stuff but I need to know if there is a way to do this. I have been using my SRX system (2x SRX715, 2x SRX718) with subs coupled to one side for a few months now. Didn't do it for the longest time I suppose because of how it looked on stage and I never ran out of steam power wise so hardly ever really needed to but I have found I really like the thump I get this way and want to get the best out of the system.
However, my water hose size speakon cables are a pain to lay out and take down so I'd really like to just run one cable to the subs and one to the 715 same side so I'm not running 3 cables. Isn't there a way to connect the subs together but NOT bridge the amp whilst only using one output ? I'd like to use both sides of the amp keeping it at 8 ohms per side if possible.
Title: Re: Best way to configure XTI6002
Post by: Tim McCulloch on April 21, 2014, 10:40:36 PM
I know this is probably basic stuff but I need to know if there is a way to do this. I have been using my SRX system (2x SRX715, 2x SRX718) with subs coupled to one side for a few months now. Didn't do it for the longest time I suppose because of how it looked on stage and I never ran out of steam power wise so hardly ever really needed to but I have found I really like the thump I get this way and want to get the best out of the system.
However, my water hose size speakon cables are a pain to lay out and take down so I'd really like to just run one cable to the subs and one to the 715 same side so I'm not running 3 cables. Isn't there a way to connect the subs together but NOT bridge the amp whilst only using one output ? I'd like to use both sides of the amp keeping it at 8 ohms per side if possible.

Help me understand: you have the 715s set up left/right, and the pair of subs on one side only?

The channel 1 NL4 output has channel *2* on pins 2+-.  Put your amp on whatever side of the stage the subs are on, run an NL4 from output 1 to the first sub, then use an NL4 jumper to the 2nd sub, then jump to the 715, and then use a long NL4 to jump to the other 715.  IIRC the processing puts the sub signal on channel 2, so you would flip the switches on your 718s to take signal from pins 2+- and pass through the pin 1/channel 1 signal to the 715.  You'd only have one 4 conductor cable crossing the stage.
Title: Re: Best way to configure XTI6002
Post by: Paul G. OBrien on April 21, 2014, 10:43:20 PM
Isn't there a way to connect the subs together but NOT bridge the amp whilst only using one output ?
Yes you connect channel A of the amp to the first sub and then connect the second sub to the first. Do the same with the 715s as well connecting them to channel B.

 
I'd like to use both sides of the amp keeping it at 8 ohms per side if possible.
This will use both sides of the amp but the resulting load is 4 ohms because two 8ohm speakers in parallel equals 4 ohms. It is not possible to connect all these speakers to a single amplifier and maintain an 8 ohm load.. assuming you want separate crossover frequencies and EQ for the subs and tops.
Title: Re: Best way to configure XTI6002
Post by: Jonathan Betts on April 21, 2014, 10:47:56 PM
Help me understand: you have the 715s set up left/right, and the pair of subs on one side only?

The channel 1 NL4 output has channel *2* on pins 2+-.  Put your amp on whatever side of the stage the subs are on, run an NL4 from output 1 to the first sub, then use an NL4 jumper to the 2nd sub, then jump to the 715, and then use a long NL4 to jump to the other 715.  IIRC the processing puts the sub signal on channel 2, so you would flip the switches on your 718s to take signal from pins 2+- and pass through the pin 1/channel 1 signal to the 715.  You'd only have one 4 conductor cable crossing the stage.

This is how I run my 715/718 setup off one IT 6000.
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 21, 2014, 10:58:32 PM
Help me understand: you have the 715s set up left/right, and the pair of subs on one side only?

The channel 1 NL4 output has channel *2* on pins 2+-.  Put your amp on whatever side of the stage the subs are on, run an NL4 from output 1 to the first sub, then use an NL4 jumper to the 2nd sub, then jump to the 715, and then use a long NL4 to jump to the other 715.  IIRC the processing puts the sub signal on channel 2, so you would flip the switches on your 718s to take signal from pins 2+- and pass through the pin 1/channel 1 signal to the 715.  You'd only have one 4 conductor cable crossing the stage.

Yes Tim- sorry....you understand fully - I just didn't explain well. That is exactly right....one SRX715 on one side and the other 715 along with the 2 subs on the other side.
Your suggestion would be perfect except I am already using 4 pole speakon cable to bi-amp the SRX715's.........(probably should have mentioned that too - again sorry)
I must admit though I had forgotten that the SRX has that capability...

I wonder if I would lose quality if I didn't bi-amp. I use a DBX drive rack + set at 3 way and I really like being able to have complete control over the highs and mids.  I use the JBL published tunings. 
However, I have read opposing views on this. Some say there is no better way to run the SRX's than the way the JBL engineers  have designed them as full range (passive c/o)  but then others have said bi-amping offers far better control over crossover freq/slopes, high/mid gains etc and the sound is superior.

I used to use the 715's full range when I first got them but went bi-amp almost immediately and haven't really considered going full range again. I remember thinking the bi-amped speakers sounded better to me (of course - otherwise I wouldn't have invested the time and energy into making the change I suppose) but I wonder if it would really make enough difference to the listener.  Enough of a difference to prevent me from wiring the subs as you suggested....
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 21, 2014, 11:01:12 PM
Yes you connect channel A of the amp to the first sub and then connect the second sub to the first. Do the same with the 715s as well connecting them to channel B.

  This will use both sides of the amp but the resulting load is 4 ohms because two 8ohm speakers in parallel equals 4 ohms. It is not possible to connect all these speakers to a single amplifier and maintain an 8 ohm load.. assuming you want separate crossover frequencies and EQ for the subs and tops.
Thanks Paul.... I was busy typing my response to Tim when you posted this. I use 2 x 6002 amps and use one for the mids and one for the subs. I use an XLS2000 for the horns. The system is 3 way right now.
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 21, 2014, 11:06:17 PM
This is how I run my 715/718 setup off one IT 6000.

How do you get on using just the one amp for the whole system? I use two and the XLS2000 for the horns as I just explained to Paul. The resulting wattage rating is about the same per side but I wonder if there is much of a benefit using two  XTI6002's and the XLS2000 to power the horns????   
Title: Re: Best way to configure XTI6002
Post by: Tim McCulloch on April 21, 2014, 11:08:39 PM
Thanks Paul.... I was busy typing my response to Tim when you posted this. I use 2 x 6002 amps and use one for the mids and one for the subs. I use an XLS2000 for the horns. The system is 3 way right now.

Tri-amped?  No cable savings for you today.

I'd suggest simply trying the 715s passive.  You can do this a couple of ways - 1 amp for the tops and the other for the subs, or do a sub/top on each amp.  In this case put both amps on the sub side of the stage, run a long NL4 to the 715 on the far side, plug it into Channel 1, and use a short jumper to the sub on channel 2; use short cables to power the near-side from the other amp.

I'm not going to say you wont hear a difference, but the question becomes does any perceived difference make up for the added cabling weight and complexity?
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 21, 2014, 11:23:15 PM
Tri-amped?  No cable savings for you today.

I'd suggest simply trying the 715s passive.  You can do this a couple of ways - 1 amp for the tops and the other for the subs, or do a sub/top on each amp.  In this case put both amps on the sub side of the stage, run a long NL4 to the 715 on the far side, plug it into Channel 1, and use a short jumper to the sub on channel 2; use short cables to power the near-side from the other amp.

I'm not going to say you wont hear a difference, but the question becomes does any perceived difference make up for the added cabling weight and complexity?

I've actually never used the DSP in the amps other than limiting - in the XLS2000 into the horns mainly.
Your second option would presumably allow me to use the c/o settings in the amps and actually eliminate (if running passive tops) my Crown XLS2000, my DBX DRPA and a whole bunch of cabling.........tempting but I'd have to spend some time doing some comparisons.
Problem is whenever I try to do something like this, it takes so long for me to rewire everything, by the time I have it up and running, I have forgotten what it sounded like before.....
Title: Re: Best way to configure XTI6002
Post by: Tim Padrick on April 21, 2014, 11:34:52 PM
Once you have it set up, monitor the amp with your computer.  Especially when used for subs, it's very easy to have a configuration in which the amp's output is not what clips first, unless you boost the output section quite a bit (8dB in a friend's case).
Title: Re: Best way to configure XTI6002
Post by: Jonathan Betts on April 21, 2014, 11:43:20 PM
The only time I ever bi amp my 715's is when I'm running four 718's and I need just a little more output from the cabinet. 715's(passive) are perfect when mixed with a couple of 718's.

One amp, one NL4 from channel 1 to sub, one 20amp circuit....
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 12:17:13 AM
The only time I ever bi amp my 715's is when I'm running four 718's and I need just a little more output from the cabinet. 715's(passive) are perfect when mixed with a couple of 718's.

One amp, one NL4 from channel 1 to sub, one 20amp circuit....


Do you notice much of a difference in overall quality when you bi-amp the 715's??

I run my system pretty modestly usually from one 20 circuit and I have never yet had any problems with running the 3 amps off one receptacle. However, running one amp would have an advantage there.
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 12:19:42 AM
Once you have it set up, monitor the amp with your computer.  Especially when used for subs, it's very easy to have a configuration in which the amp's output is not what clips first, unless you boost the output section quite a bit (8dB in a friend's case).
That would be unknown territory for me !!!
Title: Re: Best way to configure XTI6002
Post by: Tim McCulloch on April 22, 2014, 12:27:30 AM
I've actually never used the DSP in the amps other than limiting - in the XLS2000 into the horns mainly.
Your second option would presumably allow me to use the c/o settings in the amps and actually eliminate (if running passive tops) my Crown XLS2000, my DBX DRPA and a whole bunch of cabling.........tempting but I'd have to spend some time doing some comparisons.
Problem is whenever I try to do something like this, it takes so long for me to rewire everything, by the time I have it up and running, I have forgotten what it sounded like before.....

I just opened System Architect 3.30 and loaded the SRX/Xti2 device files into a virtual 6002.  You want preset #2.  :)

Two amplifiers, Debbie.  Only 1 long cable.  Less filling, saves the puppies & kittens, etc.

Padrick's suggestion about monitoring your amps is good.  You need either Band Manager or System Architect. The XTi only have USB connections, but if both amps are set the same you probably need to monitor only 1 of them.  The software is free at http://hiqnet.harmanpro.com/software/
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 12:37:56 AM
I just opened System Architect 3.30 and loaded the SRX/Xti2 device files into a virtual 6002.  You want preset #2.  :)

Two amplifiers, Debbie.  Only 1 long cable.  Less filling, saves the puppies & kittens, etc.

Padrick's suggestion about monitoring your amps is good.  You need either Band Manager or System Architect. The XTi only have USB connections, but if both amps are set the same you probably need to monitor only 1 of them.  The software is free at http://hiqnet.harmanpro.com/software/

That would mean bridging the amp though right? I have always tried to avoid bridging amps - I know I shouldn't be worried especially with an amp like this but I try really hard to keep my amps running cool with minimum distortion.
I'd also have to limit the amp quite a bit as the rating according to JBL is 6000 watts into 4 ohms right? Or did you find a way to use one cable without bridging?? BTW... I really appreciate you looking into this for me  :)

The only time I used system architect was to update the firmware in the amps. I've never used it for anything else. I suppose I should check it out !!
Title: Re: Best way to configure XTI6002
Post by: Tim McCulloch on April 22, 2014, 12:57:59 AM
That would mean bridging the amp though right? I have always tried to avoid bridging amps - I know I shouldn't be worried especially with an amp like this but I try really hard to keep my amps running cool with minimum distortion.
I'd also have to limit the amp quite a bit as the rating according to JBL is 6000 watts into 4 ohms right? Or did you find a way to use one cable without bridging?? BTW... I really appreciate you looking into this for me  :)

The only time I used system architect was to update the firmware in the amps. I've never used it for anything else. I suppose I should check it out !!

No, the amp will not be bridged, although it uses the "Input Y" setting to send the Channel 1 input to both channels.

In System Architect (and probably Band Manager) I was able to have independent pass band output levels for the preset I mentioned.  You can hype (or not) the subs to your liking.  It was for this that Padrick suggested real time monitoring of amp i/o levels.  Once you get used to your rig this way, you'll probably not need to monitor the amp(s) unless you are doing something new or pushing it harder than previously.

A quick look inside shows peak voltage limiters for each pass band are already set.  Debbie, it's really this simple.  I know, it's not supposed to be - and don't tell anyone about the magic inside the boxes and how you turned speaker cables into thin air. 8)

Triamping with these products, while instructive (and therefore valuable as an academic exercise), it provides little net gain at showtime unless you're already working close to the edge or in some VERY dicey acoustic environments.  I've been down this road out of necessity, 25+ years ago.  With today's gear it's not so necessary...
Title: Re: Best way to configure XTI6002
Post by: Cailen Waddell on April 22, 2014, 08:04:52 AM
Debbie if you have an iPad, the crown USBx is also a monitoring option....
Title: Re: Best way to configure XTI6002
Post by: Jerome Malsack on April 22, 2014, 08:27:57 AM
For the one cable solution you will need the 8 wire in one cable.  NL8 connectors. 
http://www.parts-express.com/neutrik-nl8mpr-speakon-connector-8-pole-chassis-mount--092-055

You would have to see if the speakers have the NL8  or make a box for the receiving end at the stage behind the speakers.   

We run the NL8 for tri amp system and it works very well having one cable to the far side to run tops and subs.  You might be able to run the last pair as a monitor send also. 
Title: Re: Best way to configure XTI6002
Post by: Mike Karseboom on April 22, 2014, 11:08:44 AM

Your desire to tri-amp is what forces the cable count up.  For the configuration you describe  there are many ways you could go but here is one way to keep the cables to a minimum.  This is easy to do and does not require any soldering but is somewhat verbose to describe.

You need  (times 2) 
  2' chunk of 4C speaker cable
  NL4 connector
  NL4 coupler (NL4MXX)


Make a short pigtail that will allow you to patch the output from your XTi6002 and XLS2002 into a single 4 conductor speaker cable:


  -  Attach the NL4 speakon connector to one end


  -  strip back the outer cover on the other end far enough to leave individual conductors long enough to stretch between the XLS2002 and the XTi6002 in the amp rack.
 
  -  Use the screw terminals on the backs of the amps to attach the bare ends.


  xti6002 ch1 +   ----->      NL4 1+ 
             ch1 -    ------>     NL4 1-
  xls2002 ch1 +  ------->    NL4 2+
              ch1-    ------->    NL4 2-


Use the speakon couplers to attach the pigtail NL4 to a regular 4C speaker cable of the desired length.  This is the cable that will plug into the SRX715 for Bi-Amp operation.


You need to make an identical set up for the "other" side (left vs right.)


With these two pigtails you can run your cables as follows assuming the amps are on the right side and the subs are clustered near the amps.  All amps run stereo


XLS2002       ch1
XTi6002 #1   ch1      --->  pigtail   ---->  4C cable to 715 Left (long)


XLS2002       ch2   
XTi6002 #1   ch2   --->  pigtail   ---->   4C cable to 715  right (short)


XTi6002 #2    ch1  ---->   718   (short)
                    ch2  ----->  718   (short)


                       
This setup lets you do it with 1x long 4C cable and 3x short 4C cables.  You can just leave the pigtails wired up in the amp rack whether you use them or not.


Again lots of variations you could use and also ways to pretty up the pigtails with banana plugs or additional NL4's at the amp end. You still need the driverack though as no other way to split the signals up for tri-amp.


                   






  -
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 05:04:55 PM
Gonna get my rack out of the trailer and play. Mike....I tried to follow your instructions and I got a little lost I am afraid. I enjoy wiring racks - I built a nice patchbay in mine to easily connect my biamped 4 pole speakon cables and my XLR inputs to my DRPA. So doing some creative wiring would not be a problem but I couldn't follow and lost the plot I'm afraid. I do appreciate the time you took putting all the info together though.
I'll read it again with the amps in front of me and see if I can understand it better.
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 05:07:33 PM
No, the amp will not be bridged, although it uses the "Input Y" setting to send the Channel 1 input to both channels.

In System Architect (and probably Band Manager) I was able to have independent pass band output levels for the preset I mentioned.  You can hype (or not) the subs to your liking.  It was for this that Padrick suggested real time monitoring of amp i/o levels.  Once you get used to your rig this way, you'll probably not need to monitor the amp(s) unless you are doing something new or pushing it harder than previously.

A quick look inside shows peak voltage limiters for each pass band are already set.  Debbie, it's really this simple.  I know, it's not supposed to be - and don't tell anyone about the magic inside the boxes and how you turned speaker cables into thin air. 8)

Triamping with these products, while instructive (and therefore valuable as an academic exercise), it provides little net gain at showtime unless you're already working close to the edge or in some VERY dicey acoustic environments.  I've been down this road out of necessity, 25+ years ago.  With today's gear it's not so necessary...

Hey Tim....Like I just told Mike I'm gonna play a bit with the amps and the wiring to see what I can come up with. Good to know that I have options though...keeps things interesting for me !!!
Title: Re: Best way to configure XTI6002
Post by: Jens Droessler on April 22, 2014, 09:03:10 PM
So you already have 4wire cabling to your SRX715. That's good. If you like to biamp the 715s, keep it that way. There are numerous advantages in biamping. Many of them will work out well if you bring the 715s to high power, which I guess isn't something you do everyday, since two SRX718 are enough low end for your application.

To address your problem: Why don't you use a 4wire cable for the subs too? Channel A of your sub amp will be on 1+/1- of the NL4 speakon, channel B will be on 2+/2-. All you have to do is to plug this 4wire cable in the first SRX718, put another short 4wire cable between the two SRX718 and set the switch below the speakon connectors on sub 1 to 1+/- and the switch on sub 2 to 2+/-. Every subwoofer no connects to his own channel of your amplifier and you have to run only one 4wire cable to the subs.

Another tip: If you'd like to simplify your setup, get rid of the XLS2000 and the DriveRack+ and get another Xti6002. Now use one Xti6002 per SRX715 (ch A for the 15 and ch B for HF or the other way around) and use the internal DSP (I guess there are fitting setups available). A further advantage to this would be that you could drive both SRX715 biamped mono from one amp without reconfiguring anything if one of the Xtis dies.
Title: Re: Best way to configure XTI6002
Post by: Debbie Dunkley on April 22, 2014, 10:26:54 PM
So you already have 4wire cabling to your SRX715. That's good. If you like to biamp the 715s, keep it that way. There are numerous advantages in biamping. Many of them will work out well if you bring the 715s to high power, which I guess isn't something you do everyday, since two SRX718 are enough low end for your application.

To address your problem: Why don't you use a 4wire cable for the subs too? Channel A of your sub amp will be on 1+/1- of the NL4 speakon, channel B will be on 2+/2-. All you have to do is to plug this 4wire cable in the first SRX718, put another short 4wire cable between the two SRX718 and set the switch below the speakon connectors on sub 1 to 1+/- and the switch on sub 2 to 2+/-. Every subwoofer no connects to his own channel of your amplifier and you have to run only one 4wire cable to the subs.

Another tip: If you'd like to simplify your setup, get rid of the XLS2000 and the DriveRack+ and get another Xti6002. Now use one Xti6002 per SRX715 (ch A for the 15 and ch B for HF or the other way around) and use the internal DSP (I guess there are fitting setups available). A further advantage to this would be that you could drive both SRX715 biamped mono from one amp without reconfiguring anything if one of the Xtis dies.

Oh yeah duh !!! That makes complete sense using the switches to select the different connections for the subs only - even though they are typically used to send signal through and up into the mids. Well that is a great idea and easily doable !!
Purchasing another XTI6002 even if I were to sell my XLS and DRPA would be a bit of a stretch for me right now though and I am on restriction spending PA money for the time being. My GAS had gotten out of control and my husband insisted we start paying the mortgage instead !!! he he