Debating whether to go Pre Amp/Power Amp...Need help...

[Tony G]

For the inputs, you need a special XLR Y-cable. One side needs to be wired normal and the other side (which goes to channel two) needs to be wired with reversed polarity. If you don't know how to do this, I'm sure you could find someone handy with a soldering iron to make one for you for a nominal fee. If your preamp only has quarter inch outputs, you will need something like an Whirlwind IMP impedance adapter to go on the single end of the cable.

The output just needs a Speakon wired for bridge-mono mode.

That sounds a little complicated.... I think I won't bridge anything for a while, and see if it works out for me.

Also, I am having a little trouble understanding the ohm situation of the stereo mode. It says it runs 600watts and 4ohms, stereo. Does that mean it is only running 300 per channel, or is it saying it is 600 per channel? Also, if I run my 4 ohm B410 Neo in one channel, and another 4 ohm cab in the other channel, does that bring it down to 2 ohms like on most amps, or are they independant of each other and it just runs at 4 ohms? I'm a little confused with all of this...

 

[Jack]

If it says 600W stereo, then each channel will do 600W.
600Wx2, if you like.

Each channel is independant, a 4ohm cab and one channel and another cab on the other channel will mean each side of the amp will give 600W and hence each cabinet will get 600W all to itself. You can run different loads on each channel, even no load on one of them.

 

[Tony G]

If it says 600W stereo, then each channel will do 600W.
600Wx2, if you like.

Each channel is independant, a 4ohm cab and one channel and another cab on the other channel will mean each side of the amp will give 600W and hence each cabinet will get 600W all to itself. You can run different loads on each channel, even no load on one of them.

Interesting. so I could run a 4 ohm load rated at 600w into one channel, and run an 8 ohm load from the other channel and have the same 600 watts, or different?

 

[McHack]

Anyways, I have gotten off topic. I went to my local music store and tested a BBE Bmax through a Crown XLS 402. It was the brightest, cleanest signal I have yet experienced. Is this the way I should go? Is a pre/power setup better than a head?

Please help me decide.

I play a Crown XLS 402, bridged thru an Ashdown RPM-1 (thx again Tom!), which feeds 2 Aggie GS112's. My 402 is rated 260 @ 8ohms per side, bridged-mono, 800w @ 8, 1140 @ 4ohms. That's what I'm running into my two GS112's. I havent needed to crank it, so I'm still feeling that out.

BUT, This past weekend, I was able to A/B'ing my rig, to an Eden 410 + a Navigator, being powered by an Eden Power Amp. We had 'em both run flat.

What I came away with is, the Ashdown/Aggie combination CAN get bright, but you're gonna have to EQ it in. The Aggie/Ashdown combination, sounded full & round & deep, while retaining some nice clarity. The Navigator/410 sounded clear clear clear to me w/ some great punch, I can see why folks love 'em. Also, on my GS112's,, one of them is of the NT variety, & I keep the tweeter on the standard GS, almost off.

But, I digress. I picked up my XLS 402 off Ebay for some insanely cheap price, approx $120. THAT's what set me in motion, to a pre/power rig. My reasoning was, I could afford to bite off smaller pieces, where as dumping a load of cash for a whole HEAD,,, might be tougher to sell to MrsHack.

Am I happy? Yes! I have a powerful, great sounding rig, thats portable & fits in my RX7.

 

[Lowtonejoe]

Interesting. so I could run a 4 ohm load rated at 600w into one channel, and run an 8 ohm load from the other channel and have the same 600 watts, or different?

Do you have the two space or the three space xls?



Joe.

 

[McHack]

That sounds a little complicated.... I think I won't bridge anything for a while, and see if it works out for me.

Also, I am having a little trouble understanding the ohm situation of the stereo mode. It says it runs 600watts and 4ohms, stereo. Does that mean it is only running 300 per channel, or is it saying it is 600 per channel? Also, if I run my 4 ohm B410 Neo in one channel, and another 4 ohm cab in the other channel, does that bring it down to 2 ohms like on most amps, or are they independant of each other and it just runs at 4 ohms? I'm a little confused with all of this...

Having read a little further, I can reply to this.

When, I bought the XLS402, I thought I was going to be powering a 4ohm GS410. Who knows, at some point, I still maybe... Had the cables made & everything, but then found I just cant fit a 6u rack AND a GS410 into my RX7....

So, I started looking for something portable,, hence the GS112's. Thier power rating is substantially lower than that of a GS410, so I was a little scared to bridge the amp & daisy chain the 2 112's.

I had researched power amps & was sold on a QSC PLX series. They have external dip switches which make configuring your amp EZ! The Crown XLS series, are a no frills Class B amp. You're limited as to what type of connectors you can use. Dont get me wrong, they're a steal. No switches, or anything. You have to bridge it, by using cross-wired cables to force the amp to bridge itself.

It works just great. Its just not as clear cut, that you're actually bridged or not. No light, no switch... I had Butch from Bayou Cables make mine, but any capable electrician should be able to hook you up.

Oh, another thing... it only weighs like 25lbs... 1140w @ 4ohms bridged!!! That's not too shabby!

 

[Tony G]

Do you have the two space or the three space xls?



Joe.

I have the XLS 602 which is 2 rack spaces

 

[Tony G]

Cool...Thanks for the help McHack!

 

[Lowtonejoe]

I have the XLS 602 which is 2 rack spaces

FWIW you can use any typical (+1,+2 to +1,-1) 'Bridged Mono' cable to bridge your speakon output.

Also you can make and adapter to go from stereo speakon to stereo 1/4" if you prefer 1/4" connectivity.



Joe.

 

[Tony G]

FWIW you can use any typical (+1,+2 to +1,-1) 'Bridged Mono' cable to bridge your speakon output.

Also you can make and adapter to go from stereo speakon to stereo 1/4" if you prefer 1/4" connectivity.



Joe.

Cool, thanks. I prefer Speakons, so I will probably have Bayou cables make them up for me.

 

[Lowtonejoe]

Cool, thanks. I prefer Speakons, so I will probably have Bayou cables make them up for me.

Cool.

I just recently bought some cord wraps from Butch.

My order was put into the mail the same day I placed it!

Are you thinking of going bridged mono or having him make up a stereo splitter for you?

Or both?



Joe.

 

[McHack]

Are you thinking of going bridged mono or having him make up a stereo splitter for you?

I was able to find the necessary connectors at GC to power my XLS in stereo. I started w/ a 1/4" plug -> XLR converter... Then, I found an XLR splitter. Hooked 'em together & its F'in majik!

The only reason I bridged, is because I only take one cab to practice. That means I'm only pushing 1 channel, w/ 260w at 8ohms. Its loud enough, but I had to push hard enough that it used up any head room the amp had left.

 

[Tony G]

Cool.

I just recently bought some cord wraps from Butch.

My order was put into the mail the same day I placed it!

Are you thinking of going bridged mono or having him make up a stereo splitter for you?

Or both?



Joe.

Jeez...I don't know. My first thought was to go Bridged mono, but what does the stereo splitter do again?

 

[Lowtonejoe]

I was able to find the necessary connectors at GC to power my XLS in stereo. I started w/ a 1/4" plug -> XLR converter... Then, I found an XLR splitter. Hooked 'em together & its F'in majik!

The only reason I bridged, is because I only take one cab to practice. That means I'm only pushing 1 channel, w/ 260w at 8ohms. Its loud enough, but I had to push hard enough that it used up any head room the amp had left.

Cool man.

That is a great solution.

But I'm talking about the outputs. The XLR's are inputs.



Joe.

 

[McHack]

Cool man.

That is a great solution.

But I'm talking about the outputs. The XLR's are inputs.



Joe.

GAH... I really need to read things thoroughly.

I had Butch make me a cross-wired speakon -> speakon, cable to use for bridged output, when I ordered my bridge wired Y-splitter. Then, for adding a 2nd cab, I just went 1/4" out of lead cab -> speakon to 2nd cab.

 

[Lowtonejoe]

Jeez...I don't know. My first thought was to go Bridged mono, but what does the stereo splitter do again?

It lets you, if you want to, run both your left and right channels down to 2 ohms.

If you want to hook up a 4 ohm cab on one side and an 8 ohm cab on the other you can do that too. Or any combination thereof down to 2 ohms.

BUT...you get more power into 4 ohms bridged mono (one 4 ohm or two 8 ohm cabs) than you will running dual mono.

Since you will be running the same preamp signal into both channels you get what is called 'dual mono' instead of stereo.



Joe.

 

[Lowtonejoe]

GAH... I really need to read things thoroughly.

...snip...

I hear you man. I've done the same thing too many times!



Joe.

 

[Tony G]

It lets you, if you want to, run both your left and right channels down to 2 ohms.

If you want to hook up a 4 ohm cab on one side and an 8 ohm cab on the other you can do that too. Or any combination thereof down to 2 ohms.

BUT...you get more power into 4 ohms bridged mono (one 4 ohm or two 8 ohm cabs) than you will running dual mono.

Since you will be running the same preamp signal into both channels you get what is called 'dual mono' instead of stereo.



Joe.

So.... Do I need a xlr y-splitter from the output of the pre to the input of the power, and a cross wired speakon to run it bridged mono? Or do I just plug the pre into the first channel and used the cross wired speakon from bridged mono? I'm so confused....Please set me straight on this...

 

[McHack]

So.... Do I need a xlr y-splitter from the output of the pre to the input of the power, and a cross wired speakon to run it bridged mono? Or do I just plug the pre into the first channel and used the cross wired speakon from bridged mono? I'm so confused....Please set me straight on this...

I wasnt sure of this... So, I called Butch, & told him what I had, & what I wanted to do... He said, "Oh yea, I'm REALLY familar w/ the Crown XLS amps. I use one!"

He told me, what I needed.

 

[Tony G]

I wasnt sure of this... So, I called Butch, & told him what I had, & what I wanted to do... He said, "Oh yea, I'm REALLY familar w/ the Crown XLS amps. I use one!"

He told me, what I needed.

Ok, cool.. I will just give Butch a call then and have him help me out. Thanks!