Power consumption rating for AVRs/Amps

P

PENG

Audioholic Slumlord
First of all, power consumption is simply the power consumed by the unit. Given that there appear to be no universal standards on this rating for AVRs and there are different amp classifications such as A, AB, A/AB, D, G H etc.; all having different typical efficiencies, one cannot easily relate power consumption figures to the amplifier outputs accurately. I just want to share my own observations from reading manuals and specs over the years as to why one should be careful in trying to draw conclusions from power consumption figures provided at the back of the units, spec sheets, or manuals.

Amps and AVRs manufacturers don't seem to have the same standard to follow in rating their so call power consumption figures. Below are some examples.

Denon& Marantz


  • Typically provide a figure they simply refer to as 'Power consumption', in the manuals, spec sheets or at the back of their units.
  • In some models (the older ones), the unit they used for power consumption could be VA (apparent power) or A (current in amperes), while in other modes (the newer ones), they seem to have standardized on W.
Yamaha

  • Provides both 'Power consumption' and 'Maximum power consumption' in their manuals but just 'Power consumption' at the back of the units.
Onkyo

  • Provides A (current in amperes) , for North American models and W for the European models.


Since Yamaha recently seems to have standardized on providing both power consumption and maximum power consumption, let's take a look of their new model.

RX-A3040

Power consumption as stated in the manual

Canada model: 400W
Korea model: 390W
Other model: 490W (that apparently includes the USA model).
Maximum power consumption: 1210W (Asia and General models)
Power consumption as shown at the back of the unit: 490W (USA model)

So we can see that there don't seem to be a standard that these manufacturers are using. I like the fact that Yamaha provides two figures though.


Now let's take a look of the Onkyo flag ship model as well.

Since Onkyo provides both A and W, we can do the math for their TX-NR5010 model as follow.

I(Current)=12.4A, V(Voltage) =120Volts (manual page 122)

Power consumption in W (Real power) = 1160W (manual page 122)

Calculations

Power consumption in VA (Apparent power) =VI = 120X12.4 = 1488VA

Power factor = Real power/Apparent power = 1160/1488 = 0.78

From what I can see, it is not possible to compare the power consumption figures among different AVRs, let alone trying to deduce their audio power output from those figures.

The only reasonable assumptions I dare make are:

1) Maximum power consumption figures provided by some manufacturers such as Yamaha and HK are not continuous ratings but could probably be reached during peaks in normal use without endangering the unit, though the power supply will most likely be overloaded at those consumption levels.

2) Power consumption is probably defined by the manufacturers based on their own perception of normal use, or they based it on certain existing standards or rules that have not been adopted universally. If that is the case (I am not sure), those figures could mean different things among different manufacturers.

3) Base on the Denon and Onkyo specs, I would consider a power factor or 0.8 a safe assumption if anyone want to convert from VA or A to W, by applying either one of the formula below.

W (watts) = VA X 0.8, if power consumption is given in VA.

W (watts) = 120 (North American voltage) X A X 0.8, if power consumption is given in A (current/amperes).
 
Last edited by a moderator:
M

markw

Audioholic Overlord
Obviously, watts are different depending on what country you're in. :rolleyes:
 
slipperybidness

slipperybidness

Audioholic Warlord
You make a few good points.

My opinion would be that apparent power would be the best spec to go by. Now, if they would just get it somewhat standardized across the board.

Perhaps including this in 3rd part measurements would be of use.
 
P

PENG

Audioholic Slumlord
Obviously, watts are different depending on what country you're in. :rolleyes:
Obviously, but it could also be due totally or partially to different rules that they have to follow in different countries. Who knows..
 
P

PENG

Audioholic Slumlord
You make a few good points.

My opinion would be that apparent power would be the best spec to go by. Now, if they would just get it somewhat standardized across the board.

Perhaps including this in 3rd part measurements would be of use.
I totally agree, I wish Denon had sticked to A, or VA. For a lot of people though, they are more familiar with watts and may have no idea what VA is.
 
P

PENG

Audioholic Slumlord
Sorry guys I have to keep editing my post because things got weird when you do it in MS Word and then do the copy and paste thing.
 
slipperybidness

slipperybidness

Audioholic Warlord
Obviously, but it could also be due totally or partially to different rules that they have to follow in different countries. Who knows..
Well, how about for the good ole US of A we convert those Watt numbers into good old-fashioned Horsepower Ratings?

i.e. My Pio elite puts out 0.2 HP! or 200 mHP. Bazinga:cool:
 
P

PENG

Audioholic Slumlord
Well, how about for the good ole US of A we convert those Watt numbers into good old-fashioned Horsepower Ratings?

i.e. My Pio elite puts out 0.2 HP! or 200 mHP. Bazinga:cool:
Great point, most NA are much more familiar with HP than watts for sure. Besides, flag ship D&M and Onkyo units do get pass the fractional horse power range so they have not much to be ashamed of.
 
M

markw

Audioholic Overlord
Obviously, but it could also be due totally or partially to different rules that they have to follow in different countries. Who knows..
Obviously, this site could use a "sarcasim" icon. :cool:
 
M Code

M Code

Audioholic General
First of all, power consumption is simply the power consumed by the unit. Given that there appear to be no universal standards on this rating for AVRs and there are different amp classifications such as A, AB, A/AB, D, G H etc.; all having different typical efficiencies, one cannot easily relate power consumption figures to the amplifier outputs accurately. I just want to share my own observations from reading manuals and specs over the years as to why one should be careful in trying to draw conclusions from power consumption figures provided at the back of the units, spec sheets, or manuals.

Amps and AVRs manufacturers don't seem to have the same standard to follow in rating their so call power consumption figures. Below are some examples.

Denon& Marantz


  • Typically provide a figure they simply refer to as 'Power consumption', in the manuals, spec sheets or at the back of their units.
  • In some models (the older ones), the unit they used for power consumption could be VA (apparent power) or A (current in amperes), while in other modes (the newer ones), they seem to have standardized on W.
Yamaha

  • Provides both 'Power consumption' and 'Maximum power consumption' in their manuals but just 'Power consumption' at the back of the units.
Onkyo

  • Provides A (current in amperes) , for North American models and W for the European models.


Since Yamaha recently seems to have standardized on providing both power consumption and maximum power consumption, let's take a look of their new model.

RX-A3040

Power consumption as stated in the manual

Canada model: 400W
Korea model: 390W
Other model: 490W (that apparently includes the USA model).
Maximum power consumption: 1210W (Asia and General models)
Power consumption as shown at the back of the unit: 490W (USA model)

So we can see that there don't seem to be a standard that these manufacturers are using. I like the fact that Yamaha provides two figures though.


Now let's take a look of the Onkyo flag ship model as well.

Since Onkyo provides both A and W, we can do the math for their TX-NR5010 model as follow.

I(Current)=12.4A, V(Voltage) =120Volts (manual page 122)

Power consumption in W (Real power) = 1160W (manual page 122)

Calculations

Power consumption in VA (Apparent power) =VI = 120X12.4 = 1488VA

Power factor = Real power/Apparent power = 1160/1488 = 0.78

From what I can see, it is not possible to compare the power consumption figures among different AVRs, let alone trying to deduce their audio power output from those figures.

The only reasonable assumptions I dare make are:

1) Maximum power consumption figures provided by some manufacturers such as Yamaha and HK are not continuous ratings but could probably be reached during peaks in normal use without endangering the unit, though the power supply will most likely be overloaded at those consumption levels.

2) Power consumption is probably defined by the manufacturers based on their own perception of normal use, or they based it on certain existing standards or rules that have not been adopted universally. If that is the case (I am not sure), those figures could mean different things among different manufacturers.

3) Base on the Denon and Onkyo specs, I would consider a power factor or 0.8 a safe assumption if anyone want to convert from VA or A to W, by applying either one of the formula below.

W (watts) = VA X 0.8, if power consumption is given in VA.

W (watts) = 120 (North American voltage) X A X 0.8, if power consumption is given in A (current/amperes).
Here is a good article written by Gene explaining some of the basics..
Additionally in my experience, UL uses the manufacturer's published specs for power and impedance as a basic reference point..

http://www.audioholics.com/audio-amplifier/impedance-selector-switch-1/what-is-ul-csa-actually-testing
Just my $0.02... ;)
 
Last edited by a moderator:

Latest posts

newsletter

  • RBHsound.com
  • BlueJeansCable.com
  • SVS Sound Subwoofers
  • Experience the Martin Logan Montis
Top