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XTI 4000 20hz - 20khz watts?


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#1 difflvl

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Posted 23 October 2007 - 12:48 PM

I was wondering what are the wattage specs for the XTI 4000 at 20hz-20khz, instead of the 1khz rating. I looked all over the website and can't find it.

Thanks

#2 DGlass

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Posted 23 October 2007 - 02:57 PM

There are two standards that make it easier to compare amplifier output ratings the FTC and EIA ratings standards.
The FTC standard was established by the Federal Trade Commission and requires that a manufacturer’s stated power ratings must meet the advertised frequency range (usually 20 Hz to 20 kHz) at the rated THD (Total Harmonic Distortion) with both channels driven.
The EIA rating, established by The Electronic Industries Association, is the power output of a single channel driven at typically 1 kHz with 1% THD clipping. The EIA standard will typically be 10 to 20% higher than the FTC ratings.
We go one step further than the EIA ratings and drive both channels as we feel the fairest, most honest, and most revealing rating method is the obvious one: to specify power with all channels fully driven, as this is a more real world scenario. When fewer channels are being tested, the more power the ones that aren’t being used can deliver. This can artificially increase the apparent power output. By testing with both channels driven we are decreasing the standard 10-20% difference of one channel driven.  
What does a 10-20% power difference mean in reality? For the average person to hear a difference in loudness/level, you would need to double the power to the speakers. You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won’t hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.
To put it in a nut shell we basically provide a more conservative power spec of the EIA standard because we test with both channels driven during our tests not just one.
Since the differences between the two standards are really minimal, when you look at it, the more important questions should be things like amplifier features and reliability.


#3 difflvl

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Posted 24 October 2007 - 04:40 AM

View PostDGlass, on 23 October 2007 - 02:57 PM, said:

There are two standards that make it easier to compare amplifier output ratings the FTC and EIA ratings standards.
The FTC standard was established by the Federal Trade Commission and requires that a manufacturer's stated power ratings must meet the advertised frequency range (usually 20 Hz to 20 kHz) at the rated THD (Total Harmonic Distortion) with both channels driven.
The EIA rating, established by The Electronic Industries Association, is the power output of a single channel driven at typically 1 kHz with 1% THD clipping. The EIA standard will typically be 10 to 20% higher than the FTC ratings.
We go one step further than the EIA ratings and drive both channels as we feel the fairest, most honest, and most revealing rating method is the obvious one: to specify power with all channels fully driven, as this is a more real world scenario. When fewer channels are being tested, the more power the ones that aren't being used can deliver. This can artificially increase the apparent power output. By testing with both channels driven we are decreasing the standard 10-20% difference of one channel driven.  
What does a 10-20% power difference mean in reality? For the average person to hear a difference in loudness/level, you would need to double the power to the speakers. You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.
To put it in a nut shell we basically provide a more conservative power spec of the EIA standard because we test with both channels driven during our tests not just one.
Since the differences between the two standards are really minimal, when you look at it, the more important questions should be things like amplifier features and reliability.

Thanks for the explanation. Just out of curiosity what is the watt output  of the XTI 4000 with the FTC method?

Thanks

#4 snooty

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Posted 24 October 2007 - 08:38 AM

View Postdifflvl, on 24 October 2007 - 04:40 AM, said:

View PostDGlass, on 23 October 2007 - 02:57 PM, said:

There are two standards that make it easier to compare amplifier output ratings the FTC and EIA ratings standards.
The FTC standard was established by the Federal Trade Commission and requires that a manufacturer's stated power ratings must meet the advertised frequency range (usually 20 Hz to 20 kHz) at the rated THD (Total Harmonic Distortion) with both channels driven.
The EIA rating, established by The Electronic Industries Association, is the power output of a single channel driven at typically 1 kHz with 1% THD clipping. The EIA standard will typically be 10 to 20% higher than the FTC ratings.
We go one step further than the EIA ratings and drive both channels as we feel the fairest, most honest, and most revealing rating method is the obvious one: to specify power with all channels fully driven, as this is a more real world scenario. When fewer channels are being tested, the more power the ones that aren't being used can deliver. This can artificially increase the apparent power output. By testing with both channels driven we are decreasing the standard 10-20% difference of one channel driven.  
What does a 10-20% power difference mean in reality? For the average person to hear a difference in loudness/level, you would need to double the power to the speakers. You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.
To put it in a nut shell we basically provide a more conservative power spec of the EIA standard because we test with both channels driven during our tests not just one.
Since the differences between the two standards are really minimal, when you look at it, the more important questions should be things like amplifier features and reliability.

Thanks for the explanation. Just out of curiosity what is the watt output  of the XTI 4000 with the FTC method?

Thanks


I am also very keen to know this

#5 Blackdevil77

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Posted 24 October 2007 - 12:55 PM

Yeah id like to know this as well. I own the Xti 4000 and I think its great. Why are these specs only released on the I-techs? You said the EIA rating is typically 10-20% higher than the FTC rating. Lets say it's 15% higher. That means the rating of the Xti 4000 into 4 ohms would be 1020 watts per channel. I think it's safe to say the FTC rating of the Xti 4000 into 4 ohms is about 1000 watts per channel.

#6 difflvl

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Posted 25 October 2007 - 06:23 PM

The EIA rating IMO is useless. It doesn't tell me how much power my sub will get or anything else for that matter.

Are you guys not sharing the XTI4000 FTC figure because it is low? I know you have the figures so please share them.



#7 Blackdevil77

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Posted 25 October 2007 - 09:26 PM

View Postdifflvl, on 25 October 2007 - 06:23 PM, said:

Are you guys not sharing the XTI4000 FTC figure because it is low? I know you have the figures so please share them.

I don't think they are low. It's rare that the FTC ratings are shown. I've only seen them shown with really high end amps like the I-tech. I don't think all other amps out there that are under 2K are crap. Most companies I have seen don't show this spec.

#8 DGlass

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Posted 31 October 2007 - 01:03 PM

The FTC rating is mostly used by commercial audio products and occasionally you will see a Pro Audio Product listed with an FTC rating.
Crown does a more conservative testing of products using the EIA standard than the EIA standard requires. We test with all channels driven not just one. In this scenario if the power supply sags because of trying to push a lot of current to the load the output power will go down. This is something most manufactures do not what you know. That under full load their amps don't meet the specified output power
When you compare Crown amps to others you can be guaranteed that Crown amps will meet or exceed the specified output power per channel under a full load. :)

The 10 to 20% difference between FTC and EIA is not that much to begin with. To hear a difference in output level the output power would need to be doubled (raised by 3db). You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.

The FTC ratings were done on an the ITech amplifiers because it is our Top of the line amplifier and we wanted to. :wacko: :( :wacko:

#9 difflvl

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Posted 31 October 2007 - 11:33 PM

View PostDGlass, on 31 October 2007 - 01:03 PM, said:

The FTC rating is mostly used by commercial audio products and occasionally you will see a Pro Audio Product listed with an FTC rating.
Crown does a more conservative testing of products using the EIA standard than the EIA standard requires. We test with all channels driven not just one. In this scenario if the power supply sags because of trying to push a lot of current to the load the output power will go down. This is something most manufactures do not what you know. That under full load their amps don't meet the specified output power
When you compare Crown amps to others you can be guaranteed that Crown amps will meet or exceed the specified output power per channel under a full load. :)

The 10 to 20% difference between FTC and EIA is not that much to begin with. To hear a difference in output level the output power would need to be doubled (raised by 3db). You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.

The FTC ratings were done on an the ITech amplifiers because it is our Top of the line amplifier and we wanted to. :wacko: :( :wacko:

Thanks David,

I understand you guys test both channels simultaneously  and other people test only one. I know you guarantee your rated wattage but my question is what are the FTC numbers available for the XTI 4000?

I want to know how much power the XTI 4000 is sending to my subs (30-150hz range) hence the reason I ask for the 20hz-20khz. I bought 3 of these amps and would like to know what its putting out. I don't mean any disrespect here but it seems you posted the ratings for the ITech because they are virtually the same as the EIA ratings. I find it hard to believe the engineers at crown have not tested the XTI 4000 wattage across the full frequency range. I don't think its too much to ask for as an owner of this amp to get the 20hz-20khz power rating. If you want me to keep quiet about it I will just PM me. My suspicion is the FTC rating must be a lot lower and that is the reason you guys don't want to publish it.

difflvl

#10 snooty

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Posted 01 November 2007 - 05:08 PM

View Postdifflvl, on 31 October 2007 - 11:33 PM, said:

View PostDGlass, on 31 October 2007 - 01:03 PM, said:

The FTC rating is mostly used by commercial audio products and occasionally you will see a Pro Audio Product listed with an FTC rating.
Crown does a more conservative testing of products using the EIA standard than the EIA standard requires. We test with all channels driven not just one. In this scenario if the power supply sags because of trying to push a lot of current to the load the output power will go down. This is something most manufactures do not what you know. That under full load their amps don't meet the specified output power
When you compare Crown amps to others you can be guaranteed that Crown amps will meet or exceed the specified output power per channel under a full load. :)

The 10 to 20% difference between FTC and EIA is not that much to begin with. To hear a difference in output level the output power would need to be doubled (raised by 3db). You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.

The FTC ratings were done on an the ITech amplifiers because it is our Top of the line amplifier and we wanted to. :wacko: :( :wacko:

Thanks David,

I understand you guys test both channels simultaneously  and other people test only one. I know you guarantee your rated wattage but my question is what are the FTC numbers available for the XTI 4000?

I want to know how much power the XTI 4000 is sending to my subs (30-150hz range) hence the reason I ask for the 20hz-20khz. I bought 3 of these amps and would like to know what its putting out. I don't mean any disrespect here but it seems you posted the ratings for the ITech because they are virtually the same as the EIA ratings. I find it hard to believe the engineers at crown have not tested the XTI 4000 wattage across the full frequency range. I don't think its too much to ask for as an owner of this amp to get the 20hz-20khz power rating. If you want me to keep quiet about it I will just PM me. My suspicion is the FTC rating must be a lot lower and that is the reason you guys don't want to publish it.

difflvl

Yes we would all like to know, When deciding to purchase multiples of these amps as I am for 8 mixes of active monitors, I'd appreciate the piece of mind (at the least), considering all other cheaper options I have  had a look at display the FTC, quest, phonic etc (admit idly without inbuilt DSPs) ...  dont tell me crown arnt up to the same testing as these brands? . Its like 'this is our top speed on the straight, but we wont tell you the horsepower nor torque'

#11 difflvl

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Posted 01 November 2007 - 07:55 PM

If crown is refusing to give me ratings for a product that I bought from them and giving me a run around, then that is the last time I buy a crown amp. I'll be sure to let everyone know about this BS runaround you guys are giving me and how you guys do not want to give out the real power of the amp that you guys sell, just the "useless" 1khz figure. I have been a crown loyal until now, this really *beep*es me off.

1khz is BS marketing gimicks that companies that make weak amps use to up their wattage. Its very similar to gas mileage on a car, everyone knows the EPA ratings are with a granny driving and not normal driving. Same thing here, they use this BS 1khz to be able to publish higher wattage numbers. Who cares what the wattage is in at a single point out of the whole frequency spectrum.

Thanks for showing me what kind of company you guys really are!

#12 Blackdevil77

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Posted 02 November 2007 - 06:08 AM

Do you like the amp? Does it have enough power for whatever your using it for?

#13 Elliot Thompson

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Posted 02 November 2007 - 11:08 AM

View Postdifflvl, on 01 November 2007 - 07:55 PM, said:

If crown is refusing to give me ratings for a product that I bought from them and giving me a run around, then that is the last time I buy a crown amp. I'll be sure to let everyone know about this BS runaround you guys are giving me and how you guys do not want to give out the real power of the amp that you guys sell, just the "useless" 1khz figure. I have been a crown loyal until now, this really *beep*es me off.

1khz is BS marketing gimicks that companies that make weak amps use to up their wattage. Its very similar to gas mileage on a car, everyone knows the EPA ratings are with a granny driving and not normal driving. Same thing here, they use this BS 1khz to be able to publish higher wattage numbers. Who cares what the wattage is in at a single point out of the whole frequency spectrum.

Thanks for showing me what kind of company you guys really are!

I strongly suggest you stop and take a breather.

First. Lets look at the FTC ratings. It is measured from 20 - 20,000 KHz. Unless you are using a full range cabinet the FTC ratings doesn't hold any weight for frequencies ranging from 30 - 150 Hertz. Reasons being you are delivering a limited frequency bandwidth, which the FTC ratings (20 - 20 KHz) cannot answer. So, you are back at square one.

David Glass answered your question right here;

View PostDGlass, on 31 October 2007 - 01:03 PM, said:

The 10 to 20% difference between FTC and EIA is not that much to begin with. To hear a difference in output level the output power would need to be doubled (raised by 3db). You can hear the difference between 200 watts and 400 watts, a 3 dB increase or doubling of power, but you won't hear a difference between 200 watts and 240 watts as small difference in output power are not discernable to the human ear.

FTC ratings were also aimed towards home audio and, Crown is not obligated to use them because they left the home audio market 30+ years ago.

What matters is performance. And Crown has always been notorious for their low-end performance for decades.

Now if you still want to know the answer, you'll need to deduct the 1 KHz wattage at the given impedance by 10-20% to achieve the FTC rating of 20 - 20,000 KHz. Then, deduct the FTC frequency response to your sub frequencies (Wherever your starting and cutoff point is) at the given impedance to find the answer.

Other than gloating on having a few insignificant watts over your competitor you are not gaining anything.

Best Regards,

#14 DGlass

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Posted 02 November 2007 - 11:48 AM

View Postdifflvl, on 01 November 2007 - 07:55 PM, said:

If crown is refusing to give me ratings for a product that I bought from them and giving me a run around, then that is the last time I buy a crown amp. I'll be sure to let everyone know about this BS runaround you guys are giving me and how you guys do not want to give out the real power of the amp that you guys sell, just the "useless" 1khz figure. I have been a crown loyal until now, this really *beep*es me off.

1khz is BS marketing gimicks that companies that make weak amps use to up their wattage. Its very similar to gas mileage on a car, everyone knows the EPA ratings are with a granny driving and not normal driving. Same thing here, they use this BS 1khz to be able to publish higher wattage numbers. Who cares what the wattage is in at a single point out of the whole frequency spectrum.

Thanks for showing me what kind of company you guys really are!

Easy there Ray.
I have requested the 20-20 Khz numbers for you from our engineering department. When they are able to get to the request they will get me the info and I will get it to you.
See what type of company we are.

#15 difflvl

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Posted 02 November 2007 - 07:37 PM

View PostDGlass, on 02 November 2007 - 11:48 AM, said:

View Postdifflvl, on 01 November 2007 - 07:55 PM, said:

If crown is refusing to give me ratings for a product that I bought from them and giving me a run around, then that is the last time I buy a crown amp. I'll be sure to let everyone know about this BS runaround you guys are giving me and how you guys do not want to give out the real power of the amp that you guys sell, just the "useless" 1khz figure. I have been a crown loyal until now, this really *beep*es me off.

1khz is BS marketing gimicks that companies that make weak amps use to up their wattage. Its very similar to gas mileage on a car, everyone knows the EPA ratings are with a granny driving and not normal driving. Same thing here, they use this BS 1khz to be able to publish higher wattage numbers. Who cares what the wattage is in at a single point out of the whole frequency spectrum.

Thanks for showing me what kind of company you guys really are!

Easy there Ray.
I have requested the 20-20 Khz numbers for you from our engineering department. When they are able to get to the request they will get me the info and I will get it to you.
See what type of company we are.

Thank you