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A Crown STI is for sale on craigslist for 350. It is 800 watts a channel at 4ohms. I would be using it to power 2 sealed SI18's anyone have any experience with this amp? It is supposedly new in box never used. Sounds like a good deal since they are 679 plus tax on amazon.

I have heard pro amps don't necessarily excel at low frequencies, below 20hz. Any advice by someone with pro amp experience would be appreciated.

I was planning on trying to use an old Bob carver 300 amp first just to see how it does, it is rated 600 at 4ohms 2 channels, but if this is better I need to act soon if not already too late.

Thanks,
 

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Some pro audio amps have a built in Hpass around 10hz. Some lower. BUT Most do just fine at 20hz. Almost all Crowns have a Hpass around 10hz. Some of their higher end amps have a Hpass around 5hz.

So for the Xti you will be just fine using this as a subwoofer amp.
 

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Thanks, I am going to make an offer on it. I am sure I can sell it for close to what I pay if it doesnt work out for some reason.
 

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Are the fans on the Behringer EP fairly quiet? That look's like a good deal if they aren't too noisy.
To the OP, are you referring to the Xti 2000? I have never used one but the XLi series fans aren't noisy. Mine is barely audible within 2 feet of the amp after running it hard. Can't comment though on the under 20 hz performance of it.
I'd say that's a pretty good deal for a never used Crown.
 

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It is the XTI2000, the older model not the new one on the website. The ad is still up but no answer yet, gotta love craigslist!

I have been looking at the XLI series too, but no hurry since the subs arent built yet. I am hoping to start this weekend.

I will probably have to get a miniDSP also. I never thought I would become one of those crazy DIY sub guys I used to read about but...seems like it has come to pass.

Then there is the inuke, so many choices and considerations to make.

Which XLS do you have?
 

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I was planning on trying to use an old Bob carver 300 amp first just to see how it does, it is rated 600 at 4ohms 2 channels, but if this is better I need to act soon if not already too late.
What's the exact model number of your Carver amp?

Keep in mind that with any 20+ year old amp, unless it has been completely refurbished, it's not going to perform to its original specs.

From what little I've seen, whether an amp is pro or not has nothing to do with its frequency response. It's also pointless to go by manufacturer's specs, as almost everybody says "20-20k", but the low cutoff and slope are rarely mentioned. I suspect it may be a moving target, as it may depend on the actual value of electrolytic caps in the signal path that typically have a wide tolerance.

Sealed subs can require *lots* of power to make high output at the lowest frequencies...
 

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It is the Series II 300-2. According to the manual it is bridgeable at 4 ohms. I used it to power a pair of Axiom M80's. It was loud and clear for those speakers. I will try it just to see what it will do.
 

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Thanks for the info, but now I'm *really* confused!

It is the Series II 300-2. According to the manual it is bridgeable at 4 ohms.
Do you mean a Phase Linear 300 Series Two, or a Sunfire 300x2 series II? Neither of those are series bridgeable without an adaptor/modification. There's a Carver PM-300, but that's not rated for a 4R load when series bridged, and even then I doubt you'd safely get more than 400W.

A pic would be invaluable here...

BTW the PL300-Two (a home amp) is rated to no more than -1dB at 11Hz, but has subsonic protection to shut down if you try to drive her at 10Hz or below. The PM-300 (a pro amp) has maybe -3dB to 4Hz, and is also protected below that. The Sunfire has separate "lab direct" inputs if you want DC coupling and are feeling brave...
 

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Are the fans on the Behringer EP fairly quiet? That look's like a good deal if they aren't too noisy.
I can't speak about the EPX fan noise but if it is anything like my EP-4000 then they would be pretty quiet.
 

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Thanks for the info, but now I'm *really* confused!



Do you mean a Phase Linear 300 Series Two, or a Sunfire 300x2 series II? Neither of those are series bridgeable without an adaptor/modification. There's a Carver PM-300, but that's not rated for a 4R load when series bridged, and even then I doubt you'd safely get more than 400W.

A pic would be invaluable here...

BTW the PL300-Two (a home amp) is rated to no more than -1dB at 11Hz, but has subsonic protection to shut down if you try to drive her at 10Hz or below. The PM-300 (a pro amp) has maybe -3dB to 4Hz, and is also protected below that. The Sunfire has separate "lab direct" inputs if you want DC coupling and are feeling brave...
I looked at the manual for it today and it is not bridgeable at 4 OHM. The carver amps are somewhat hard to determine the model. I think it is the Sunfire Series II 300-2 according to user manual i looked up on the sunfire site. Looks like it anyway.
 

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Thanks, Ron!

The Sunfire 300x2 is a nice amp, pretty much the definition of "load invariant". I'm sure she'll do great at sub duty. Even though she's not set up for series bridging, you can "strap" the "current" outputs together for parallel bridging (procedure is in the owner's manual). That won't get you more power, but it'll make sure you don't "run out of steam". BTW, if she's a Series II, I believe she's actually 325x2(650x2 into 4R).

If you still have your heart set on a Crown, I'll trade you a new XTI2000 for your old Sunfire any day! :)
 
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