Rti A9 and Crown 1500

bluetrumpet01

I just recently got a pair of A9's and have been playing around with how to power them. I don't have a sub at the moment and wanted to see how well the A9s could handle the bass. I bought a Crown XLS1500 to power the pair and while it sound good, I knew they could do better. I played around with biamping one speaker and running the LFE out to Ch1 and the Sub1 out to Ch2. Now it sounds glorious, but I'm worried about sending 2x300 wpc to the A9. I'm not sure if the crown ratings are RMS or peak and I haven't seen anywhere what the peak handling of the A9 is, I just know they're 50-500 rms. Am I risking blowing the speaker?

EndersShadow

The way you've described it is confusing to me. Can you shoot some pics of your cable wiring and post them? That should help us make sure you haven't wired the speaker in a way that may blow it.

But your basic question is can the A9's handle 300 watts and the answer is YES. IIRC their rating goes up to 500 watts (though you can use more).

I know someone who bridged a Emotiva XPA-2, which makes it a 1000 watt monoblock basically, on his A9's and then cranked it and they were fine (though he didnt do it for long, as he mighta fried his drivers).

You have a better chance of blowing the speaker by using a underpowered amp (and then clipping it) than an overpowered amp.

Additionally the RMS value and its actual usage are different. Your amp isnt always putting out 300 watts RMS to the A9's unless its asked for.

I have a 375x5 amp for my LSi setup. At idle its using less than 30 watts, not the full 375x5. And even at my loudest I have yet to hear it run out of gas.

bluetrumpet01

It'll be a few hours before I can post a photo so hopefully here is a slightly clearer description. The XLS puts out 300w @ 8ohm per channel. I removed the jumpers between the posts of the A9

Receiver L preout -> Crown XLS1500 Channel 1 -> Top posts of A9


Receiver Sub1 preout -> Crown XLS1500 Channel 2 -> Bottom posts of A9

EndersShadow

No pics needed. I understand what your doing and you shouldn't do it that way.

The bottom binding post of the A9's is not a "subwoofer" its a "woofer" meaning its not meant to handle the LFE stuff. Its goal is to handle the low(er) frequencies that go to the Left or Right channel. The LFE is meant for a subwoofer ONLY, unless the speaker manufacture designates you can hook it up like that (Definitive Technology does this but I think thats it).

If you were to want to use both channels of that amp for your A9's should hook it up like this:

Run the L pre-out into a Y splitter that connects to both inputs on the Crown. Ensure the jumper is removed and run 2 sets of wires to the top and bottom of the speaker.

Its almost the same as bridging the amp and using one input and one speaker wire from the amp to the speaker with jumpers (using the same wire as the speaker wire) between the top and bottom binding posts.

bluetrumpet01

I get more power bridging the amp and just reinstalling the jumpers, no? The XLS1500 says Dual 300w@8ohm or Bridged 1,050w@8ohm (which I wouldn't do out of fear of blowing it).

The speakers handle the bass really well which is why I figured I could use them as a substitute for a good subwoofer. I'm just worried about blowing something.

EndersShadow

bluetrumpet01 wrote: »

I figured I could use them as a substitute for a good subwoofer. I'm just worried about blowing something.

Yeah, the way you do ^that, is by setting the speakers to FULL RANGE in your AVR and subwoofer to No. Then they get all the bass a subwoofer would as well.

So if thats your goal and you happen to have 2 amps at your disposal, I would use the y splitter method with each amp driving its own speaker. But the MOST important thing is to set them to FULL RANGE on your receiver. Your center should still be crossed over around 80hz and probably even your surrounds......

bluetrumpet01

I'll give that a try. Thanks Ender

Polkie2009

Good luck captain, I still think you'd be better off running a separate subwoofer for the LFE.

Inspector 24

What Polkie said.

I've powered A9's with twin Parasound HCA-3500's, that's 700wpc and I'd bet more current than the Crown can deliver. Just don't try and see how loud they can go before blowing up and you'll likely be fine.

When you're ready for a better amp, check the classifieds. There's a 3500 for sale.

bluetrumpet01

Running them full range still doesn't sound as good as sending the subwoofer output to them, but I'm just going to get a subwoofer.

EndersShadow

A dedicated sub is a better bet for sure.

Polkie2009

How many cu. ft. room are you working with there captain? What kind of budget do you have for a sub?

bluetrumpet01

the room is about 250 sqft with 12' ceilings. i'm looking at getting the psw125 to match the cherry

Polkie2009

I can totally understand you wanting to coordinate the sub to the cherry of the A9's. I've never run one of those PSW125 subs so I don't know how they would sound in a 3000 cu. ft. room, maybe others can chime in .

F1nut

The DSW Pro 660wi will be much better in all aspects.

OldSchoolPolk

Also check out the SVS and HSU options at that price point.

If you can wait a month or two the Elac units (designed by Andrew Jones) will be coming out and they have features that the other guys will be implementing eventually.

bluetrumpet01

Thanks guys

bluetrumpet01

btw oldschool, now you have me wanting one of those new elacs that don't exist yet :-P