Pioneer VSX-LX305 power usage issues

[ban25]

Isn't volume scale adjusted after calibration? On my LX305 switching depends on signal level too.

Relative scale, yes.

 

[MbphotoX]

Agreed, that's the way it should have been designed, "latched" would not make sense unless it was triggered by a fault event such as thermal overload and that's probably what was experienced during the test. Still, the OP has not posted more info about how he obtained that chart, such as, was it from some sort of the so called kill-a-watt meter, or a better meter that actually measure power consumption in terms of average, peak, etc.., and the load condition, was it just idling with different volume settings or actally playing music? Sorry if answer to my question about the measurements have been given by the op, I have only quickly browsed through the post once from beginning to end, so might have missed something.

don't think OP specified exactly what measurement device he's using.

I don't think it matters too much, though.
The device clearly shows that the Receiver switches (relay clicking) to a lower voltage rail after 25 minutes of low power draw. (I can confirm the switching, but not with measurements of my own)
OP has shown that the power drawn by the system gets roughly cut in half.
And they also stated that the power draw goes back up when the volume is turned up to -15dB (because the receiver switches back to the higher voltage rail)

No "power cycling" is needed here.

 

[peng]

don't think OP specified exactly what measurement device he's using.

I don't think it matters too much, though.
The device clearly shows that the Receiver switches (relay clicking) to a lower voltage rail after 25 minutes of low power draw. (I can confirm the switching, but not with measurements of my own)
OP has shown that the power drawn by the system gets roughly cut in half.
And they also stated that the power draw goes back up when the volume is turned up to -15dB (because the receiver switches back to the higher voltage rail)

No "power cycling" is needed here.

Thanks, I just want to know under what conditions his metering (whatever device) was measuring, and regardless, the fact that the "power" was so constant, it would have to be either a) averaged over a long period, i.e. many seconds and/or b) playing contents that are highly compressed, without much dynamic fluctuations.

 

[ban25]

Thanks, I just want to know under what conditions his metering (whatever device) was measuring, and regardless, the fact that the "power" was so constant, it would have to be either a) averaged over a long period, i.e. many seconds and/or b) playing contents that are highly compressed, without much dynamic fluctuations.

Presumably measured from the wall, where the change in amplifier draw from dynamic content is going to be minimal relative to the HDMI section, etc.

 

[popej]

Playing at -40 adds maybe 2-3W to idle power draw. Hardly visible at the scale of the graph. And sure, at this level, supply capacitors average it over time.

 

[peng]

Guys, I am in agreement, but those graphs shows something very different that seems inexplicabe but obviously there are reasons.

 

[ban25]

Guys, I am in agreement, but those graphs shows something very different that seems inexplicabe but obviously there are reasons.

It's just bad data. The OP has provided no timeline of his procedure -- when he was changing volume, changing input sources, how did he measure the result, etc. It's completely worthless data.

 

[popej]

What is inexplicable? All looks quite normal for me.

 

[peng]

What is inexplicable? All looks quite normal for me.

You just have to take another look of the OP's post and you can see clearly about the "what...."

As you said yourself, and I agreed with you: "Playing at -40 adds maybe 2-3W to idle power draw. Hardly visible at the scale of the graph."

So, if the OP measured it at around 39 W average even at the lowered rail voltage, I would have to guess that's, as another poster mentioned iirc, the power drawn by the overheads such as the video section, because 39 W would be a lot of power for average, as peak would then be anywhere from around 100 to 400W and I doubt the OP was listening at such loud level when he was playing around.

The other thing is, AVR manufacturers don't usually published the power consumption figures for the preamp/processor section, but we can get hints from their AV preamp processors such as Onkyo/Integra, Marantz, yamaha's that show consumption figures were typically around 30 (no signal) -100 W, but likely not as low as below 39 W. Switching power rail are typically done to the rail for the power amp section so it shouldn't drop to levels as low as 39 W when the power amps are used in 5.1 or 2.1 that the OP said he was listening to.

I think there is enough "why" in my question. Again, I know there are reasons, just not sure what they are, and while I could guess, I really don't want to guess. I still hope the OP will come back and provide more details of how he did those measurements, the conditions under which measurements were taken, and the devices used for the measurements. I don't expect him doing it, nor is he obligated to, I just can't help being curious on knowing the "why", that's all.

According to the OP:

Power usage goes down 50%. And that 25 minutes mark is consistent. Every time. No matter if when watching movies in 5.1 or listening music in 2.1 configuration.

 

[peng]

It's just bad data. The OP has provided no timeline of his procedure -- when he was changing volume, changing input sources, how did he measure the result, etc. It's completely worthless data.

To be fair, though, those data are only "bad" for people who are perhaps being too curious.

 

[Ken Tajalli]

Pioneer, uses what it calls "Direct Energy" concept on this amp.
It switches power usage, according to power output at the speaker terminals.
Google Pioneer "direct energy"

 

[popej]

9 amps * 2*26V supply * 50mA idle current = 23.4W idle power draw for amp section. Then the rest is about 10W.
Changing to 2*62V supply adds another 32.4W idle power.
IMO all looks reasonable. I measured my LX305 with simple plug-in socket power meter and got similar values.

My old Yamaha, which was 7.1, used about 22W idle, while on most efficient settings. I believe Yamaha had nearly class B amps.

 

[Drunkinho]

It doesn't latch into the low output mode.. as far as we know, when you crank up the volume, it will switch back to high output mode.

(I really need one of those fancy measurement thingies that OP has..)

Search for: smart socket power monitoring. Something like this:

 

[Drunkinho]

Thanks, I just want to know under what conditions his metering (whatever device) was measuring, and regardless, the fact that the "power" was so constant, it would have to be either a) averaged over a long period, i.e. many seconds and/or b) playing contents that are highly compressed, without much dynamic fluctuations.

Smart socket with power monitoring via phone app. It was basically live power consumption monitoring.

 

[Drunkinho]

Thanks, I just want to know under what conditions his metering (whatever device) was measuring, and regardless, the fact that the "power" was so constant, it would have to be either a) averaged over a long period, i.e. many seconds and/or b) playing contents that are highly compressed, without much dynamic fluctuations.

Smart socket with power monitoring via phone app. It was basically live power consumption monitoring.

It's just bad data. The OP has provided no timeline of his procedure -- when he was changing volume, changing input sources, how did he measure the result, etc. It's completely worthless data.

Worthless data? Nope. Everything is described exactly as I was testing it. Which part you don't understand?

"After 25 minutes when watching movies there is that sound exactly as it is when you are powering on the AVR. I don't know how to call it.
I was wondering what it is and if it had any impact on the AVR performance. No sound dynamic, volume changes "visible" after this "click".
I've bought power monitoring socket and connected AVR through it. Guess what is happening after those 25 minutes and that "click" sound? I've marked time of this "click" sound with red circles on the screenshot from the power monitoring app.
Power usage goes down 50%. And that 25 minutes mark is consistant. Every time. No matter if when watching movies in 5.1 or listening music in 2.1 configuration."

If you want to pick on something it could be that "50%" but this is cherry picking. You should get the point.
To be more clear on the behaviour:
1 - Power on
2 - Power Off and Power on again
3 - Power consumption goes down - listening to the music in a 2.1 configuration at around -40dB
4 - Increasing volume to -15dB - power consupmtion goes up

 

[popej]

After 25 minutes when watching movies there is that sound exactly as it is when you are powering on the AVR. I don't know how to call it.

This is sound of relay switching.

 

[Drunkinho]

I know it now (not now but since some time :>>). I was just explaining my tests etc.

 

[Drunkinho]

Just one more question if you don't mind repeating (if you did provided the info before), is the number on the Y axis %? and what's that 75 W referred to, 100%? is it something you input into the app or the app select that automatically?

No. It is not % on Y axis. Y axis = W. Peak measured W was 75 (or maybe 99 that is why it shows 99 but I do not remember ). I do not have the data on the app anymore but I can check it later today.

 

[Drunkinho]

If it is actually measured power, it is not possible for it to be so consistent regardless what you were listening to.

Why?

 

[popej]

Yes, relays are really loud in LX305.

the displayed "power" is probably/likely not actually measured "power" but voltage and then the app might just calculate power based on a fixed resistance, likely 8 ohms

The measurement is power drawn from mains socket. Voltage is constant 120V (or 230V) and there is no way to include 8 Ohm for any calculation