The Crown XLS DriveCore Thread

[littlejohn]

Hi Guys,
Does anyone know if the XLS series is capable of accepting multiple mains voltage.
ie 110-240 50/60Hz

Or is this fixed for a particular region?

TIA

Cheers
John


EDIT: found the answer are few posts up. (no!) thanks guys

 

[littlejohn]

OK.. Genuine question this time.. tried searching but didn't find anything..
Has anyone compared the XLS1500 or above with a CT series ie. CT8150 0r CT4150
Any thoughts or opinions re: SQ vs headroom?


TIA

 

[panteragstk]

With then being the same technology I don't see why they would sound any different. I've never had any issues with sound quality or anything with my XLS1500. Fantastic amp.

 

[littlejohn]

I'm curious as the spec sheet shows the Comtech Drivecore CT series has better S/N and lower THD etc..

 

[jinjuku]

I'm curious as the spec sheet shows the Comtech Drivecore CT series has better S/N and lower THD etc..

They are also a more expensive amp and lower output. They are most likely chip only amps. The XLS DriveCores have a separate output section.

 

[panteragstk]

They are also a more expensive amp and lower output. They are most likely chip only amps. The XLS DriveCores have a separate output section.

I just wonder how audible the difference would really be?

 

[littlejohn]

They are also a more expensive amp and lower output. They are most likely chip only amps. The XLS DriveCores have a separate output section.

Sort of depends how you look at it. $/Channel, it's not all that much different. But if you're looking at $/watt, then yes. The other metric in the equation would also be quality watts be quantity watts.

I just wonder how audible the difference would really be?

I was able to do A/B comparisons between the CT8150 vs XTI2 6002 vs iTech 9000HD.
For reference my AVR was a Pioneer AX10i, so for testing I ran preout from my pioneer to the crowns driving B&W CM2s


My findings at the time were.

iTech 9000HD - best sounding
* No audible hiss at all, even with ear right up against the grill in front of each driver.
* Imaging was better. Sound stage was larger more three dimensional
* Bottom end was deep and very tight.
* Mids and highs were very "clean" without any harshness

Overall I got a real sense on "WOW", similar to what I had got from demoing a pair of 805 Diamonds driven by Krell monoblocks.
At the time I was very close to upgrading my CM2s to some 805 Diamonds, but this amp (test) put a stop on it and made to do more research.


XTi2 6002 equal second with CT8150
* XTi2 6002 had an audible hiss from about 15cm away
* CT8150 was completely silent like the iTech
* Soundstage was similar between the XTi & CT
* When cranked up loud, the CT "appeared to run out of puff". I didn't do any scientific measurements, but at around -15 to about -10 on the dial, the CT's SQ started to drop a little, where as the XTi was like the iTech, it seemed to have power in reserves to keep going yo what felt like well beyond what I was game to do with the CM2s
The behaviour was a lot like what the AX10i does at about -18 to about -16. ie the SQ is "clean" and then at a certain point certain notes become acoustically offensive.

All of the crowns were heads and shoulders above my AX10i in every respect. Going back to my AX10i felt like going from lossless to lossy music. It probably wasn't quite as bad as that but very close.
Since then I've purchased a Yamaha CX-A5000 & Kef XQ30 + XQ50c (the Kefs were at a price I couldn't turn down, plus they gave more discount off the Yammy). I was quite keen on buying the CT8150, but then came across several reviews and threads on the XLS series. And it's sort of put a pause on things.
I'm a little reluctant to ask for a loan of an XLS and CT as I feel like I've run out of favours in the bank. Hence why I'm on here

 

[FozzieT]

I have the Crown XLS 1500 in my system and love it. It replaced an Emotiva UPA-200. Both cost around $350, but the Crown has twice the power and just seems to bring more of a "lifelike" quality to the music. No fan noise, extremely quiet noise floor, huge dynamic range. It made a huge difference - this is definitely the best my system has sounded.

 

[uncola]

Wow fozziet that's interesting. I guess class A/B isn't as much of a sound advantage as I thought. How are the highs of the crown vs the emotiva? That's usually where people say class d isn't as good

 

[sequential.gear]

Hello everyone!

After bumping into this thread when I was looking around the internet for pa amplifiers that were suitable for home use, I went ahead and bought a XLS 1500 drivecore, to pair with a Pro-ject Prebox, and got me the Art cleanbox pro for level matching as well.

I was really excited about all the hype, and to tell the truth... something´s not right... I´m still getting to low of a volume, as if there was no headroom nor dynamics, and I really don´t know what I´m doing wrong. I also get an unreasonable amount of hiss, with the dials at 11 o´clock on the amp. I really have to crank up the prebox, and it lacks strength, not a lot of bass, and high frequency sounds veiled and weird with artifacts, bi-dimensional, much worse than my Nad C316bee! The Art cleanbox has it´s volume set at mid level, and before connecting it to the amp and pre, it promised much, at least in the bass department! It still sounded really low and sounded strained when pushed (preamp clipping?) though...

My speakers are diy and are low sensitivity, but never had any problems with the Nad.

Has anybody got a setup close enough to mine? What am I doing wrong? Is it the Pro-ject prebox´s fault? Or the Art cleanbox pro?

I´m a bit disappointed and sad, it was a pretty big economic effort for me to spend all this money instead of going for another cheap boutique amp...

Thanks in advance guys, sorry for the poor english...

 

[AcuDefTechGuy]

People have used their Crown XLS amps with Revel Salon2 and B&W 800D2. If it's good enough for them, I am sure it's good enough.

 

[sequential.gear]

I am fully aware it is good enough for those loudspeakers, that´s why I bought it.
My question regarded something I must be doing wrong with the levels maybe, or something wrong with the preamp not being adequate.

 

[MidnightSensi2]

Where are your gain knobs at? Are you plugging unbalanced outputs into balanced or anything funky?

Sometimes the output of pre-amps are listed in the specs if you dig, and the input sensitivity is listed in the amplifier specs. The input sensitivity is a function of amplifier gain . You will want to match it with the output level of whatever is before the amp in the audio chain. This is called gain staging, the idea is maximized total system gain. Basically, clipping everything in the chain at the same point. If you clip the pre-amp before the amp, then you lost headroom. If you clip the amp before the pre-amp, then you lost headroom. If that point never comes close to being met, then someone could get by without having gain staged properly and not know it (or have it matter for practical purposes).

 

[jinjuku]

Hello everyone!

After bumping into this thread when I was looking around the internet for pa amplifiers that were suitable for home use, I went ahead and bought a XLS 1500 drivecore, to pair with a Pro-ject Prebox, and got me the Art cleanbox pro for level matching as well.

I was really excited about all the hype, and to tell the truth... something´s not right... I´m still getting to low of a volume, as if there was no headroom nor dynamics, and I really don´t know what I´m doing wrong. I also get an unreasonable amount of hiss, with the dials at 11 o´clock on the amp. I really have to crank up the prebox, and it lacks strength, not a lot of bass, and high frequency sounds veiled and weird with artifacts, bi-dimensional, much worse than my Nad C316bee! The Art cleanbox has it´s volume set at mid level, and before connecting it to the amp and pre, it promised much, at least in the bass department! It still sounded really low and sounded strained when pushed (preamp clipping?) though...

My speakers are diy and are low sensitivity, but never had any problems with the Nad.

Has anybody got a setup close enough to mine? What am I doing wrong? Is it the Pro-ject prebox´s fault? Or the Art cleanbox pro?

I´m a bit disappointed and sad, it was a pretty big economic effort for me to spend all this money instead of going for another cheap boutique amp...

Thanks in advance guys, sorry for the poor english...

By-pass your Pre-box, by-pass the Art CleanBox Pro. Go source into Crown directly.

 

[sequential.gear]

I´m plugging unbalanced into the Art cleanbox, and then balanced into the amplifier. The knobs in the converter, only one of them changes level on both channels, the other one doesn´t do anything. This one is set halfway. The amplifier input gain is set halfway as well. As is, I have to wind up the preamp to get sufficient level, but without headroom. Regardless of any adjustment on the converter, the amplifier´s noise floor is too high, and only gets acceptable when I lower input gains to 9 o´clock.
Before inserting the Art cleanbox, just the preamp and the amplifier, there was decent suggestion of bass and good HF detail, even though there wasn´t any headroom.


Here are the technical specifications of the preamp:

Pro-Ject Pre Box

Frequency response 20Hz - 20kHz (+ - 0,2 dB)
Noise floor -100dB (A weighted)
THD 0,001%
Gain 8,5dB
Pre out 1 pair RCA/Phono sockets
Output voltage typically 1V at 1kHz
Line-level inputs 2 pairs RCA/Phono sockets
Input impedance 20kohms
Trigger (Trigger Pre) 12V DC switching voltage
Trigger out 2-pole 2,5mm co-axial jack
Outboard power supply 16V/500mA AC, suitable for your country's mains supply
Power consumption 16V/200mA AC
Replacement battery remote control 2 x AAA / 1,5V
Dimensions (W x H x D) 103 x 38 x 141mm
Weight without power supply 630g

Is this a mismatch? Is the Art cleanbox the culprit being defective?

 

[sequential.gear]

I did, it´s better, but still lacks headroom...

Thanks guys for all the replies so far!

 

[sequential.gear]

I´ve red somewhere that when dealing with these kind of amplifiers, we should set the gain to max in orther to obtain the best results. It was in a test of a Thomann the T-amp pa amplifier...

 

[jinjuku]

1V is a problem since it will take 1.4v to drive the Crown to it's full potential. Now the issue may lay in the Art Clean Box. I own one and it does work.

I would go source to Clean Box to amp as a next step. Keeping the pre out of the loop for the time being.

What is your source?

 

[ahblaza]

I would suggest that as well, 1 volt is to low to drive the crown to full or max output. Again what is your source? I would also try raising the gain on the Crown as well with the source direct input to Crown if possible.
Cheers Jeff

 

[MidnightSensi2]

Gain the Crown is /fixed/. The knobs are input attentuators. So, can put those at max if the preamp doesn't have enough voltage. The preamp will clip before the amplifier in all cases (since its output voltage is below the requirement to drive the crown to where it would clip).