My experiance with a Crown XLS power amp

[PENG]

As a matter of fact, you should not hear a difference between Class A and Class AB if both amplifiers operate within their rated output limits. Only people who claim to hear a difference might have "golden ears" and are unable to prove it with double blind tests.

It would be interesting to do a DBT study on golden ears ability to score consistently higher than 50/50 using DUTs make up of say 3 class AB amps, 2 upper mid range AVRs and 1 XPA-1 (X2) based on 0.5W average output level and 64W peak and then find out if they can rank, say 10 DUT roughly in the same order.

My speakers of choice for such test would be a pair Revel, or KEF Reference series speakers with sensitivity about 88 dB @2.83V/1M and the participants will sit 10-13 ft from the speakers in quiet acoustically treated room. For preamp, I would use one of the well measured (by ASR) desktop DAC that has good volume control.

I don't think it is hard to do such a study if a few AH members (such as RichB and Boomzilla) would volunteer to organize one. I would volunteer HD and you to be the observers during the DBT sessions and ADTG to contribute the amps and AVRs (since he's a dealer).

 

[Boomzilla]

What I'd like to do is compare a Crown "pro" amp without DSP to one of their models WITH DSP. I'm pretty sure I could hear the diff, but won't know until I get some of the amps. Assuming that costs are to be minimized, the XLS-1002 seems the logical choice for the "with" candidate. What would be the equivalent Crown amp "without?"

 

[audiophool7878]

I've owned and listened critically to the original Crown XLS series amplifiers, from the XLS-1000 to the 2500. Yes, they put out a lot of power. No, they definitely were NOT ready for home audio prime-time. They had a glassy-sounding upper midrange & treble, and the lacked the delicacy of most of the amps that were intended for good home audio. Yes, the original XLS series WAS better than the amps in an AVR, but that isn't saying much. In short, I thought Andrew Robinson was deaf, on Crown's advertising staff, or else just plain nuts.

Now the series 2 XLS amps are supposed to be much better, from what I've read. As I'd expect from any "modern" class-D amp, the glassiness is reduced, and the strengths of the original XLS line (rabid-dog bass and enough power to challenge Thor) are still there. Are "true hi-fi" amps still better sounding? I think that some are, but the XLS series 2 has narrowed the gap. Compared to any AVR on the market, the Crowns still kick booty, but if you're willing to spend more money, you can do audibly better than the XLS line.

So it depends on what you want. If you have a pair of speakers that need the Crown's power to sing (I'm thinking of Magneplanars here or maybe some of the low-sensitivity British brands), then the XLS-2 line is going to be competitive with anything in its price range. But the VAST majority of "cone in box" speakers these days are designed to be close to or above 90 dB sensitivity (1W/1M) and can easily be driven by less powerful amps than the Crowns. Can you find equivalently priced amps that sound better (although with less watts)? I think you can.

But it's your money and your choice. My "advice" and a buck will get you a cup of McCoffee. Just for fun, I was gifted recently with an old amplifier from a movie theater. It was a "pro" brand from a company called "Ashly." It sports all class-A voltage gain stages and a MOSFET output. Weighs 60 lbs. but it kicks for home audio. Its only flaw is its cooling fan that is always on and sounds like a taxiing jet on the runway. Despite its age, I think it sounds better than the Crowns but that's just to my ears and in my room.

Boomzilla

Hey Boom. Im seriously considering getting a 2502 to power my Polk LSi9 speakers. They are notoriously power hungry, 4 ohm speakers. Do you think they might be the kind of speaker that would benefit from said gobs if power?

 

[Verdinut]

Hey Boom. Im seriously considering getting a 2502 to power my Polk LSi9 speakers. They are notoriously power hungry, 4 ohm speakers. Do you think they might be the kind of speaker that would benefit from said gobs if power?

No, you don't need a 775 watt/ch amplifier to drive your Polks. The XLS1002 has more than enough power to blow them up. If you get the XLS1002, be easy on the volume on them because you could damage them if you put too much power into them. As per their specs, the LSi9s are designed to work with amplifiers with a power rating of 20 to 200 watt maximum. And 200 watts is about the maximum power it will sustain for a peak lasting a fraction of a second. What preamplifier or AVR would you use to drive a Crown? For that purpose, an AVR would need to have pre-outs.

I don't know what is the size of your listening room neither the distance is your listening position from the speakers. It's possible that your Polks cannot handle the power you would like to drive them with and you might have to replace them. It's also possible that the SPL you like to play your system at could damage your hearing. I suggest that you verify the power you need at the following link:

Peak SPL Calculator

 

[audiophool7878]

No, you don't need a 775 watt/ch amplifier to drive your Polks. Theb XLS 1000 has more than enough power to blow them. If you get the XLS1000, be easy on the volume on them because you could damage them if you put too much power into them. As per their specs, the LSi9s are designed to work with amplifiers with a power rating of 20 to 200 watt maximum. And 200 watts is about the maximum power it will sustain for a peak lasting a fraction of a second. What preamplifier or AVR would you use to drive a Crown? For that purpose, an AVR would need to have pre-outs.

I don't know what is the size of your listening room neither the distance is your listening position from the speakers. It's possible that your Polks cannot handle the power you would like to drive them with and you might have to replace them. It's also possible that the SPL you like to play your system at could damage your hearing. I suggest that you verify the power you need at the following link:

Peak SPL Calculator

Thanks for your reply. Well my road has been a long and bumpy one. Most recently I just bought (and then returned 2x pb2000s) Gave em a ride for the 45 day trial and decided they were not for me. I anticipated being more interested in movies but I quickly realized that musicality was hugely important to me and the pb2000 pair just wasnt scratching my itch for punchy midbass and articulation. It is entirely possible that i just hadnt gone far enough down the rabbit hole (mini dsp, etc) to get them tuned just right but I just had a feeling that I should return them before time was up, especially with holiday sales just around the corner.

Anyhow, to answer your question, I have a Denon 5308ci that I have been using to power my 5 speaker lsi system for the past 2 months. The Denon is very powerful and capable but I used to have an outlaw 7500 powering this system and the Denon just cant reliably get the volume to where I need it to be and I don't want to risk harming the speakers or the receiver. I am currently on a budget of $1500 and if possible I would like to get something to power at minimum the front L and R for music and also get a subwoofer. So at the moment i am trying to decide between 3 outlaw 2220 monoblocks for the flc for about $1,100 shipped and perhaps save a bit more for a subwoofer, or get a crowne of some variety and have enough left over to get a pretty decent sub now. I guess the crowne is an amazon product so its fairly safe to try and I can return it quite easily if needed. My room size is not critical at the moment because I am going to be moving in a few months and the space I will have going forward is unknown but most likely I wont be in anything bigger than a medium sized room as prescribed by bass a holics.

Your thoughts?

 

[lovinthehd]

The 1502(s) would be more than enough (and has slightly better spec than the 1002). I've got a 2502 hooked up right now only because I bought it for a future diy sub project and thought I'd put it to use in the meantime, plus it was the first gen 2 XLS I'd used (have four XLS1500s). If you don't get silly with the volume you probably wouldn't blow up your speakers. Three of the 2220s if the package deal is going is pretty attractive too but if you don't mind the aesthetics the XLS are great values IMO.

That said, hard to imagine a 5308 not being sufficient for those speakers, let alone the only slightly more powerful 7500 (that's like a 1-2 dB advantage at best for the 7500).

 

[PENG]

Hey Boom. Im seriously considering getting a 2502 to power my Polk LSi9 speakers. They are notoriously power hungry, 4 ohm speakers. Do you think they might be the kind of speaker that would benefit from said gobs if power?

Only if you actually use the extra "power". Have you worked out the power need using an online calculator yet based on 4 ohms nominal, 88 dB/2.83V/1m and your distance from speakers?

The LSi9 is not that hungry and it does not have a large stomach either. Phase angle is benign according to the S&V review so they rated it "average difficulty to drive.."

Even if (unlikely) the calculator shows you need more than 200 W, you have to be careful as the speaker's power handling seems to be up to 200 W, but obviously it can handle much more for short duration.

Polk LSi9 surround speaker system Measurements | Sound & Vision (soundandvision.com)
LSi9

RECOMMENDED AMPLIFICATION: 20-200 watts/channel
EFFICIENCY (1M,1W): 88dB
IMPEDANCE: Nominal 4 Ohms

 

[jinjuku]

I've owned and listened critically to the original Crown XLS series amplifiers, from the XLS-1000 to the 2500. Yes, they put out a lot of power. No, they definitely were NOT ready for home audio prime-time. They had a glassy-sounding upper midrange & treble, and the lacked the delicacy of most of the amps that were intended for good home audio. Yes, the original XLS series WAS better than the amps in an AVR, but that isn't saying much. In short, I thought Andrew Robinson was deaf, on Crown's advertising staff, or else just plain nuts.

I've directly compared the XLS 1502 to both my Parasound HCA and Adcom GFA across multiple speakers from floor standers to bookshelf. The Crown is simply transparent and get's out of the way. The Adcom was grainy in comparison and the Parasound had tweeter hiss.

So I don't think it's civil to call someone deaf that, as far as I know, has the ability to come to an informed opinion based on his content, that hears differently than you and has PREFERENCE other than yours.

You can now get ICE and NCore based amps that are in spitting distance in regards to price that you can purchase a Crown amp for. So that may be something else to consider.

 

[audiophool7878]

The 1502(s) would be more than enough (and has slightly better spec than the 1002). I've got a 2502 hooked up right now only because I bought it for a future diy sub project and thought I'd put it to use in the meantime, plus it was the first gen 2 XLS I'd used (have four XLS1500s). If you don't get silly with the volume you probably wouldn't blow up your speakers. Three of the 2220s if the package deal is going is pretty attractive too but if you don't mind the aesthetics the XLS are great values IMO.

That said, hard to imagine a 5308 not being sufficient for those speakers, let alone the only slightly more powerful 7500 (that's like a 1-2 dB advantage at best for the 7500).

Ive used it all for a couple of months now and always felt like I needed to turn the volume into the single digits range which scares me as the denon is not rated for 4ohm operation. I dunno. Perhaps I should just sell the lsi's and get some 8ohm speakers and spend the rest on subs

 

[mazersteven]

Ive used it all for a couple of months now and always felt like I needed to turn the volume into the single digits range which scares me as the denon is not rated for 4ohm operation.

Audioholics review of that receiver states that it was stable with 4 ohm loads maybe the review was wrong

 

[audiophool7878]

Audioholics review of that receiver states that it was stable with 4 ohm loads maybe the review was wrong

Ive read that review and every other review of that receiver as many times as anyone else. Nowhere in the review are the words "this receiver is 4ohm stable" written Furthermore, based on that fact I am uncomfortable turning up the volume beyond -15 because I cannot affort to replace the Denon and or my speakers if something goes wrong.

 

[lovinthehd]

Ive used it all for a couple of months now and always felt like I needed to turn the volume into the single digits range which scares me as the denon is not rated for 4ohm operation. I dunno. Perhaps I should just sell the lsi's and get some 8ohm speakers and spend the rest on subs

It'll do just fine at 4 ohms.

 

[audiophool7878]

It'll do just fine at 4 ohms.

But what about turning it up louder? to -8 for instance. What about crossing them over at 60 hz instead of the 80hz that I have been working with? What about running 5 of them at -8 during loud passages of Transformers? This is what Im worried about. These speakers dip below 3ohm at certain frequencies below 400 hz

 

[audiophool7878]

It'll do just fine at 4 ohms.

I know you have been a long time member of this forum and that you make contributions quite often, but if you've never owned Polk LSis and tried to power them loudly with a Denon 5308, would it not be wise to take a step back from making such sweeping declarations? I mean that question honestly and respectfully.

 

[mazersteven]

But what about turning it up louder? to -8 for instance. What about crossing them over at 60 hz instead of the 80hz that I have been working with? What about running 5 of them at -8 during loud passages of Transformers? This is what Im worried about. These speakers dip below 3ohm at certain frequencies below 400 hz

I've run a 7.1 LSi9 system crossed at 60hz with a Denon 4806. No Issues

 

[audiophool7878]

I've run a 7.1 LSi9 system crossed at 60hz with a Denon 4806. No Issues

Were you comfortable pushing the volume into the the single digits range and playing it that way for the duration of a movie? Say between -10 to -5 db on the dial?

 

[mazersteven]

Were you comfortable pushing the volume into the the single digits range and playing it that way for the duration of a movie? Say between -10 to -5 db on the dial?

Absolutely!!!

 

[lovinthehd]

But what about turning it up louder? to -8 for instance. What about crossing them over at 60 hz instead of the 80hz that I have been working with? What about running 5 of them at -8 during loud passages of Transformers? This is what Im worried about. These speakers dip below 3ohm at certain frequencies below 400 hz

I know you have been a long time member of this forum and that you make contributions quite often, but if you've never owned Polk LSis and tried to power them loudly with a Denon 5308, would it not be wise to take a step back from making such sweeping declarations? I mean that question honestly and respectfully.

Okay, let's back up and see what your particulars are....what distance from the speakers are you? Have you used an spl calculator to estimate your needs? Polk often comes with an exaggerated reputation for amp needs....the Polk forums are full of such. Keep in mind the surrounds won't generally have the same demands of the mains either.

If worried, just approach that level in small increments, but why would you want to lower crossover to 60 with those, tho? Looking here I'd probably raise it rather than lower it https://www.soundandvision.com/content/polk-lsi9-surround-speaker-system-measurements