Crown amplifiers vs. other amps in the audiophile world

[JerryLove]

And why do you think that's 2 volt? There is a reason for using higher voltages in pro audio... and it's not gain.

Primarily because of travel distance.

Electric dissipation to heat through a wire is a function of the voltage (among other factors). This is why powerlines are run at extremely high voltages.

In consumer gear: interconnect are generally quite short; and 1v gear is cheaper to built (There's also likely some historical "how it was already done" elements involved).

This is also why professional interconnects have interference rejection (via an inverted signal path in XLR) and consumer does not. While XLR is, simply put, better (as is 2v operation); it's also more expensive and unnecessary in most home applications.

Any idea why 2 volt, Jerry? It's really obvious.

Why do I bother answering if you are ignoring the answers?

Post hoc? Is that a real term?

http://lmgtfy.com/?q=post+hoc

 

[GrimSurfer]

[

Why do I bother answering if you are ignoring the answers?


http://lmgtfy.com/?q=post+hoc

You missed the commas. It doesn't make sense without them.

 

[JerryLove]

You missed the commas. It doesn't make sense without them.

I also missed the part where you answered any of my questions or addressed my critique of your claims.

 

[GrimSurfer]

I also missed the part where you answered any of my questions or addressed my critique of your claims.

 

[lovinthehd]

For load issues you could start with Audioholics:

https://www.audioholics.com/audio-amplifier/amplifier-classes

Here is a detailed review of the Crown XLS-1052 with measurements of power and noise:

https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-crown-xls-1502-amp.6062/

Buy whatever your want. These are not my cup of tea for usability (no triggers), ergonomics, and aesthetics.

- Rich

Well, it's a 1502 and it does have triggers, maybe not the usual consumer gear type, tho. Ergonomics/aesthetics are fine unless you like to stroke machined faceplates or need to constantly admire your purchases like some of the fancier consumer amps No happy endings, generally even from those amps priced such that someone should be included to provide such....

 

[Fateepat]

I'm late to the party on this and I have not read all the posts on this thread. I'll just bring up the fact that most "PA" amplifiers operate in the 0dB to +4 dB range, most hifi gear has outputs of -10dB or -7dB. I believe that your driving your outputs into clipping in order to drive the amp to full power......Thank you

 

[jinjuku]

I'm late to the party on this and I have not read all the posts on this thread. I'll just bring up the fact that most "PA" amplifiers operate in the 0dB to +4 dB range, most hifi gear has outputs of -10dB or -7dB. I believe that your driving your outputs into clipping in order to drive the amp to full power......Thank you

You can't swing a dead cat by the tail without hitting a DAC that has +4 XLR. Also the Gen 2 Crowns have true consumer level inputs. So if you have RCA that can go 1.5-2 volt you will have no problem with gain structure.

 

[PENG]

2) Signal to noise at full rated power is often deceiving. At 1 watt what is it?

Hello Rich, I don't remember if I responded to this question here, or at ACR before so I may be repeating..

Amir does not always specify the power output level on his chart and in this case he has not. So we can reasonably assume he measured it at rated output of 300 W into 8 ohms, or 5 W per his typical "dash" board setting.

If it was at rated output of 300 W, then SNR of 100 dB, then worse (just my assumption) case scenario based on the same input signal:

SNR is signal to noise ratio so if noise remain the same (again, worse case)then refer to 1 W by calculation:

SNR should drop to approx. 75 dB

If the measured 100 dB was based on his dash board power output level at 5 W, then refer to 1 W by calculation:

SNR should drop to about 86 dB

Formula used:
P2/P1 in dB = Log10(P2/P1), or if you prefer voltage:
V2/V1 in dB = 20*Log10(V2/V1), and you can calculate V2/V1 easily because V2/V1 = SQRT(P2/P1)

P2 is Power output level for the measurement
P1 is Power output level used as reference, so if 1 W is the reference:
P2/P1 = P2, that is, the output level used for the measurement, and
V2/V1 = Square root of P2

75 dB SNR may not be as bad as it looked as Amir did it using 22.5 kHz BW and did not mention what kind, if any, filter was used.

As Gene mentioned before (https://www.audioholics.com/audio-amplifier/basic-amplifier-measurement-techniques)

"We like to see an amplifier be able to deliver at least 80 dB @ 1 watt to ensure it has a low enough noise floor to not mask subtle details of music when listening at low power levels. "

Again, note that on ACR's chart, there was no mentioning of what kind of filter, or none, used.., unless I missed something.

It would be great if everyone clearly state the conditions of their measurements but unfortunately that seems like a very tall order.

Review and Measurements of Crown XLS 1502 Amp

This is a review and detailed measurements of the Crown XLS 1502 "PA" Power Amplifier. It is on a kind loan from a member who bought it new and drop shipped it to me. It retails for USD $349 including free Prime shipping from Amazon. At that price, it seems like an incredible value. I have...

www.audiosciencereview.com

 

[RichB]

Hello Rich, I don't remember if I responded to this question here, or at ACR before so I may be repeating..

Amir does not always specify the power output level on his chart and in this case he has not. So we can reasonably assume he measured it at rated output of 300 W into 8 ohms, or 5 W per his typical "dash" board setting.

If it was at rated output of 300 W, then SNR of 100 dB, then worse (just my assumption) case scenario based on the same input signal:

SNR is signal to noise ratio so if noise remain the same (again, worse case)then refer to 1 W by calculation:

SNR should drop to approx. 75 dB

If the measured 100 dB was based on his dash board power output level at 5 W, then refer to 1 W by calculation:

SNR should drop to about 86 dB

Formula used:
P2/P1 in dB = Log10(P2/P1), or if you prefer voltage:
V2/V1 in dB = 20*Log10(V2/V1), and you can calculate V2/V1 easily because V2/V1 = SQRT(P2/P1)

P2 is Power output level for the measurement
P1 is Power output level used as reference, so if 1 W is the reference:
P2/P1 = P2, that is, the output level used for the measurement, and
V2/V1 = Square root of P2

75 dB SNR may not be as bad as it looked as Amir did it using 22.5 kHz BW and did not mention what kind, if any, filter was used.

As Gene mentioned before (https://www.audioholics.com/audio-amplifier/basic-amplifier-measurement-techniques)

"We like to see an amplifier be able to deliver at least 80 dB @ 1 watt to ensure it has a low enough noise floor to not mask subtle details of music when listening at low power levels. "

Again, note that on ACR's chart, there was no mentioning of what kind of filter, or none, used.., unless I missed something.

It would be great if everyone clearly state the conditions of their measurements but unfortunately that seems like a very tall order.

Review and Measurements of Crown XLS 1502 Amp

This is a review and detailed measurements of the Crown XLS 1502 "PA" Power Amplifier. It is on a kind loan from a member who bought it new and drop shipped it to me. It retails for USD $349 including free Prime shipping from Amazon. At that price, it seems like an incredible value. I have...

www.audiosciencereview.com

View attachment 32797

Hi @PENG,



Eye-balling this measurement (8 Ohms is about the same), distortion is about .03 or -70dB down, which is close to your estimate.

If you have a 90 dB efficient speaker, then that is 20 dB of distortion.
Audibility extends below the noise floor of the room. My room at quietest moments is about 40 dB but this noise is not high frequency. It's anecdotal but, you can hear a pin drop. What is the dB of that sound, clearly below the noise floor.

The Audioholics recommendation of THD+N of 80dB is 0.01% at 1 watt. The Crown is not bad.
The issue remains that this is a test signal but driving a resistive load and real loads and signals could be much worse depending on the design.

It a very different amp and a 9x price but this is an interesting set of measurements of the AHB2 by JonMarsh:

Benchmarking the Benchmark... AHB2 Amplifier - HTGuide Forum

You know, sometimes you know right away good things are happening. In this case, there is no mystery... I've seen the other reviews... I've seen John Atkinson's measurements on Stereophile... The Benchmark AHB2 is a nicely proportioned little amp that seeing just a picture of the front may not...

www.htguide.com

It's possible with with more careful approach to lead dress and the test setup, I could have gotten better numbers than this, but let's leave that for the future for now.

One of the things one ought to do to appreciate this amp is compare what it's THD+N figures look like at 100mW compared to may other "high end" amps out there- here, we're coming in at 0.003%, and I've seen many amps for 10X the money coming in at 0.02 to 0.07% at 100mW. For a speaker that's 90 dB efficient, 100mW is a conversational playback level.

By 1W we're down to 0.001% THD+N, and 20W we've reached 0.0003%! Yes, three zeros in front of that 3!

Most of the time, I listen to music at conversational levels for the first watt import to me.

- Rich

 

[PENG]

Hi @PENG,

View attachment 32815

Eye-balling this measurement (8 Ohms is about the same), distortion is about .03 or -70dB down, which is close to your estimate.

If you have a 90 dB efficient speaker, then that is 20 dB of distortion.
Audibility extends below the noise floor of the room. My room at quietest moments is about 40 dB but this noise is not high frequency. It's anecdotal but, you can hear a pin drop. What is the dB of that sound, clearly below the noise floor.

The Audioholics recommendation of THD+N of 80dB is 0.01% at 1 watt. The Crown is not bad.
The issue remains that this is a test signal but driving a resistive load and real loads and signals could be much worse depending on the design.

It a very different amp and a 9x price but this is an interesting set of measurements of the AHB2 by JonMarsh:

Benchmarking the Benchmark... AHB2 Amplifier - HTGuide Forum

You know, sometimes you know right away good things are happening. In this case, there is no mystery... I've seen the other reviews... I've seen John Atkinson's measurements on Stereophile... The Benchmark AHB2 is a nicely proportioned little amp that seeing just a picture of the front may not...

www.htguide.com

Most of the time, I listen to music at conversational levels for the first watt import to me.

- Rich

I don't know about class D amps, for typical class AB amps, the talks of real load vs resistor test load are generally over exaggerated. I don't think I am the only one who find 70-75 dB average is quite loud so less than 0.5 WPC is enough for 89 dB/2.83V/m and 4 ohm nominal speakers sitting 12 ft from a single speaker. So even to cover the rare 20 dB peaks, a real 100 WPC amp or at the most 200 WPC should have no issue in terms of real speaker load and test resistor load.

Phase angle related issues also tended to be too much exaggerated as it really is mainly a thermal issue, that high phase angle means more "watts" dissipated in the output devices so beefy heat sinks and/or adequate use of fans should solve that in most cases (there are always exceptions..). Again, I don't know enough about the Crown amp/class D amp though so I'll take your word for it.

By the way, my earlier post was only about different SNR at difference output level (the point you raised), not THD+N/SINAD..

 

[RichB]

I don't know about class D amps, for typical class AB amps, the talks of real load vs resistor test load are generally over exaggerated. I don't think I am the only one who find 70-75 dB average is quite loud so less than 0.5 WPC is enough for 89 dB/2.83V/m and 4 ohm nominal speakers sitting 12 ft from a single speaker. So even to cover the rare 20 dB peaks, a real 100 WPC amp or at the most 200 WPC should have no issue in terms of real speaker load and test resistor load.

Phase angle related issues also tended to be too much exaggerated as it really is mainly a thermal issue, that high phase angle means more "watts" dissipated in the output devices so beefy heat sinks and/or adequate use of fans should solve that in most cases (there are always exceptions..). Again, I don't know enough about the Crown amp/class D amp though so I'll take your word for it.

By the way, my earlier post was only about different SNR at difference output level (the point you raised), not THD+N/SINAD..

I completely agree with the power these real-world power requirement sentiments.

I know you have compared well made amplifiers to good quality AVRs and found little or no audible difference. Given the low levels, any differences (if present) would not be a function of power but of linearity into load (not commonly considered distortion). Amplifiers also differ in their protection systems which affect performance.

Some updated topology class a/b and class-d amps measure considerably better that classic A/B topologies.

- Rich

 

[AcuDefTechGuy]

My current view on Pro amps:

1. Good sound quality - at least as good as any built-in plate amps for active subs and active speakers. I've used the Class-D amps (Crown XLS and Yamaha PX3). They sounded great.

2. Can be more economical.

3. I think the Yamaha PX3 is the best looking pro amp, but they are all much uglier than most audiophile amps, not including anything from Emotiva since I think Emotiva products are cheap looking blue cheese.

4. Low pride of ownership. Most people don't "brag" about owning pro amps. And this is a big reason I don't have any Yamaha PX3 amps, which would be great for all my passive subs.

 

[everettT]

My current view on Pro amps:

1. Good sound quality - at least as good as any built-in plate amps for active subs and active speakers. I've used the Class-D amps (Crown XLS and Yamaha PX3). They sounded great.

2. Can be more economical.

3. I think the Yamaha PX3 is the best looking pro amp, but they are all much uglier than most audiophile amps, not including anything from Emotiva since I think Emotiva products are cheap looking blue cheese.

4. Low pride of ownership. Most people don't "brag" about owning pro amps. And this is a big reason I don't have any Yamaha PX3 amps, which would be great for all my passive subs.

I brag . I really prefer them when possible and light weight rackable is a plus for me.

 

[AcuDefTechGuy]

I brag

Really? What do you tell your friends and family?

"I totally love my pro amps. They look much better than Emotiva amps that costs a lot more, don't sound any better, and don't have any kind of repair service after warranty"?

 

[everettT]

Really? What do you tell your friends and family?

"I totally love my pro amps. They look much better than Emotiva amps that costs a lot more, don't sound any better, and don't have any kind of repair service after warranty"?

They know me from my esoteric days, so I tell them that if they want more bang for their buck, go for it.

 

[Shanman]

Emotiva- Cheap blue cheese.....bwaaaahaaaahaa

With the Crowns, I do wish there was a single slot "box" available to make it more stack friendly and get rid of the visible rack ear look...

 

[AcuDefTechGuy]

They know me from my esoteric days, so I tell them that if they want more bang for their buck, go for it.

Definitely bang for your buck.

I would have loved it if they had put the Yamaha PX3 pro amps inside the Yamaha MX-A5000/5200 11Ch amps.

 

[Verdinut]

I would have loved it if they had put the Yamaha PX3 pro amps inside the Yamaha MX-A5000/5200 11Ch amps.

I think that Yamaha did well by not installing PX3 amps inside their MX-A5000/5200 11ch amps. Those pro amps have quite inferior specs than any of their audiophile power amps.
IMO, the Crown XLS 1502 and the Yamaha PX3 are adequate as Class D subwoofer amplifiers but their high THD figures with either no published frequency range or limited to the frequency of 1 kHz only don't inspire much trust as to their overall performance as high fidelity amplifiers.
Crown's intermodulation distortion figure of <0.3% is not acceptable for hi-fi or studio playback. Yamaha doesn't even publish their IM figures in their specs. Shame on Yamaha!
Crown XLS 1502: THD: <0.5% no frequency specified and power output not specified ! That's a totally unacceptable spec which doesn't qualify it as a true modern high-fidelity product.
Yamaha PX-3: THD: 0.1% (1kHZ, 10W), 0.3% (1kHz, Half power) Those are totally unacceptable specs as well.

On the other hand, QSC Audio are not afraid to publish more detailed specs on their Class AB amps:

Live Audio Series Model RMX 1450a: THD: FTC Rating 20 Hz-20 kHz = 0.1% @ 260W (8 Ohms) - IM Distortion (SMPTE): <0.01%

Digital Cinema Series DCA 1622: THD: FTC Rating 20 Hz-20 kHz = 0.03% @ 300W ( 8 Ohms -both ch driven) -IM Distortion (SMPTE): <0.01%

 

[lovinthehd]

I think that Yamaha did well by not installing PX3 amps inside their MX-A5000/5200 11ch amps. Those pro amps have quite inferior specs than any of their audiophile power amps.
IMO, the Crown XLS 1502 and the Yamaha PX3 are adequate as Class D subwoofer amplifiers but their high THD figures with either no published frequency range or limited to the frequency of 1 kHz only don't inspire much trust as to their overall performance as high fidelity amplifiers.
Crown's intermodulation distortion figure of <0.3% is not acceptable for hi-fi or studio playback. Yamaha doesn't even publish their IM figures in their specs. Shame on Yamaha!
Crown XLS 1502: THD: <0.5% no frequency specified and power output not specified ! That's a totally unacceptable spec which doesn't qualify it as a true modern high-fidelity product.
Yamaha PX-3: THD: 0.1% (1kHZ, 10W), 0.3% (1kHz, Half power) Those are totally unacceptable specs as well.

On the other hand, the QSC Audio are not afraid to publish more detailed specs on their Class AB amps:

Live Audio Series Model RMX 1450a: THD: FTC Rating 20 Hz-20 kHz = 0.1% @ 260W (8 Ohms) - IM Distortion (SMPTE): <0.01%

Digital Cinema Series DCA 1622: THD: FTC Rating 20 Hz-20 kHz = 0.03% @ 300W ( 8 Ohms -both ch driven) -IM Distortion (SMPTE): <0.01%

You might want to review the measurements in this review https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-crown-xls-1502-amp.6062/

 

[Verdinut]

You might want to review the measurements in this review https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-crown-xls-1502-amp.6062/

Have you read Amir's conclusions?

Conclusions
It is hard to fathom that a properly engineered and produced mainstream brand amplifier with so much power can be sold for so little money. This is a robust but bargain amplifier designed for heavy punishment in live sound. Can it be used for hi-fi use? Sure but it will severely limit both the resolution and potentially bandwidth of upstream sources. Its best use would be as a subwoofer amplifier. If you need an all in one unit, Hypex NC400/NC500 designs are so far my choice among amplifiers tested.