Power Amp Bridging

slinky005

slinky005

Power User
I just got one of these:
http://www.crownaudio.com/en-US/products/xls-1500

I'm trying to get more power out of it by bridging it.
I know next to nothing about these amps and how they work
Can anyone tell me if using the Speakon outs make it "bridgeable"?

I've followed the manual , and the LCD screen is saying what it should but I hear no difference in volume.
 
I am not sure if you are aware but you need to rewire one end of your speaker cable. (the one that attaches to the power amp)

Keep in mind there are different speak-on connectors, 2 pole, 4 pole. You will need just (1) 4 pole connector.

Like this: NL4FX

http://www.neutrik.com/en/speakon/spx-series/

If you got your cable from Guitar Center or whatever, chances are pretty good you have 2 pole connectors.


In the Manual:

“b. If using a Speakon® connector, connect the positive terminal of the speaker to 1+ and the negative terminal to 2+. Plug the connector into the Channel 1 output only.”

So basically- Take the NL4FX apart you will see 4 pole’s marked 1+, 1-, 2+, 2-. Take your speaker cable remove one end attach one wire to terminal 1+ and 2+ of the NL4fx connector. You’re done, no soldering involved. The 4 pole (in this case NL4FX) goes to channel 1 of your power amp. The other end to your cabinet. Don’t forget to make sure the power amp is in “bridging mode”


On the off chance you already have 4 pole connectors on your cable, you just need to rewire to one side.

Take apart one side to see what you have.


John
 
No that adapter won’t cut it.

I also re-read your post and am a little unclear, do you already have a speak-on to speak-on cable?

If so and you want to run bridged mono, in the speak-on environment, yeah you going to have to redo one of the ends, with the 4 pole end NL4FX. However! There is still another choice.


I am going to assume for now that your speaker cable is speak-on and also assume your speaker cab is speak-on/ ¼ mono.

On the speaker cable you could replace one end with a Banana plug and use the binding post on the power amp if you are not comfortable changing the speak-on connections.


I guess the breakdown would be this.

Speak-on to speak-on (at least one side 4 pole)

Even if you got a cable 4 pole both sides you would still have to crack it open to reconfigure one side.
Also! It would now be a special purpose cable to run “bridged mono” and that would be its only function.


The next two can be bought off the shelf:

Banana jack to speak-on (assuming your cab has a speak-on connector)
Or ---
Banana jack to ¼ mono (assuming your cab has a ¼ jack)
No re-wiring involved and would not be considered a “special purpose” cable, so you could re-use with anything else.
Right now I am experimenting with a Carvin power amp running it “bridged mono” for a cable I am going Banana jack to speak-on.

BTW, no matter which cable program the poweramp for "Bridged mono"
And yes you will here a volume difference.

John
 
It appears to me as though you must use the two red binding post outs to bridge that amp and NOT the speakon outs. This is common with several other amps I've seen as well. If you look at the photo of the speaker outs it shows which of the red posts is + and which is - in bridge mode (channel 1 red is + channel 2 red is -). In other words remove the speakon connector from the end of the cable you're attaching to the amp and either use banana jacks, bare wire, or attach flat blade connectors to that end of the cable.
 
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It would be far better if you use the Speakon connection as described in post #2 by 6L6C or on page 4 of the owner's manual. The connector is easy to make up and It's a way easier connection to deal with when setting up and tearing down not to mention the fact that it won't come out once it's installed correctly.
 
t0aj15 said:
It appears to me as though you must use the two red binding post outs to bridge that amp and NOT the speakon outs.
Click to expand...
With most power amps using speak-on you would be correct. But this one is designed to bridge channels using speak-on from the channel 1 connection. The channel one connection has a 4 pole configuration just for this purpose. Pretty neat really!
It comes down to whatever floats your boat. Me personally I prefer speak-on to speak-on, good connection but it lock's like (Sixstring) pointed out.
 
I am understanding more now.
My Speakon connectors are two pole and I need 4 pole.
I need to go from the Speakon to my Marshall cab (1/4")
My adapter is a Speakon / 1/4" inch in one.
http://www.neutrik.com/en/accessories/circular-adapters/na4ljx
I understand that it will be mono.
So back to the store to exchange for a 4 pole.
Looked on youtube and since there's no soldering involved (I suck at it) I have no apprehension about doing the proper wiring.
Thx guys, really appreciate it.
 
If you are going to a Marshall cab with 1/4 jack, don't even bother with speak-on.
Go Banana jack to 1/4 phone, off the shelf cable no rewiring needed.
Of coarse don't forget to program the power amp for Bridged Mono.

John
BTW that is a shit-load of power to be sending that cab, especially in Bridged Mono
Be VERY careful with the volume
 
6L6C said:
If you are going to a Marshall cab with 1/4 jack, don't even bother with speak-on.
Go Banana jack to 1/4 phone, off the shelf cable no rewiring needed.
Of coarse don't forget to program the power amp for Bridged Mono.

John
BTW that is a shit-load of power to be sending that cab, especially in Bridged Mono
Be VERY careful with the volume
Click to expand...
Well right now in non-bridged mode I'm at half volume with the Axe on full and I can tell there won't be enough headroom at full. The whole reason for my post is that I'm not getting enough volume. I'm comparing to my JVM 100watt (power amp only, Axe into serial loop) and the Crown is not as loud.
Is there something I have to do other than set the menu to bridged if using the banana jack?
 
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So I exchanged my Speakon for a bannana jack.
Did the trick.
Volume is nowhere near "dangerous" even at half way, but now I have the headroom I need (i think).
Not sure if there is an impedance mis-match or that's exactly how loud it should be.
Thanks to this forum I solved my problem really quickly.
Cheers to all who responded.
 
You may find that the pots on the amp are not fully linear so the majority of volume will come from around 2 o'clock onwards on the volume. Be careful in Bridged though if you do adjust and test it out.
 
Lightningboy said:
You may find that the pots on the amp are not fully linear so the majority of volume will come from around 2 o'clock onwards on the volume. Be careful in Bridged though if you do adjust and test it out.
Click to expand...
Cool. Look forward to seeing smoke come out of the cab!
 
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