View Full Version : When 'OFF' isn't really off.
Certainly with my pre which defaults to input 1 when unplugged but not when just switched off normally. Thus some part of it must remain powered up for the rest of the time. I wonder how much hardware still draws some current unless switched off at the mains? My power amp has a permanent trickle charge but at least this is explained in the handbook. :scratch:
A lot of gear is like that. My dac never even had an off button.
Just FYI, IEC60065 requires that the power consumption is documented both in standby and when fully operational.
Simon_LDT
25-02-2016, 13:46
But what about when not in standby, but turned off completely (but still plugged in to the mains)? My amps are always turned off after use (don't like leaving them in standby) but the mains is left on as per the manual. My pre has settings (dimmer, input select) that stay the same but soon as I turn off the mains, it reverts back to default. Which obviously means there is power still being used even when the amp is ''switched off''.
Standby is exactly what you describe. It doesnt mean being on but turned down.
IIRC such standy should be <1W.
Audio Advent
26-02-2016, 01:00
But what about when not in standby, but turned off completely (but still plugged in to the mains)? My amps are always turned off after use (don't like leaving them in standby) but the mains is left on as per the manual. My pre has settings (dimmer, input select) that stay the same but soon as I turn off the mains, it reverts back to default. Which obviously means there is power still being used even when the amp is ''switched off''.
How does it get turned off completely? By a physical rocker switch? What's the pre-amp (so we can look on the internet, even at it's insides perhaps)?
What's the time difference between you switching it off completely and unplugging it from the mains? If you unplug it from the mains for days and notice this happening but only "switch it off completely" for a couple of hours whilst you're still in the house, it could simply be that you're not "switching it off completely" for long enough for the selector memory power to drain fully and forget.. if you see what I mean.
Audio Advent
26-02-2016, 01:03
My pre amp (Pass Labs X2) doesn't even have a power switch - only turns off when you pull the IEC plug out the back! I leave everything on unless I go away. My smart metre for the electricity doesn't show any difference between turning it all off and playing music at normal levels but then I'm using 94% efficient class D amps and there's not much heat from them either.
Simon_LDT
26-02-2016, 01:26
How does it get turned off completely? By a physical rocker switch? What's the pre-amp (so we can look on the internet, even at it's insides perhaps)?
What's the time difference between you switching it off completely and unplugging it from the mains? If you unplug it from the mains for days and notice this happening but only "switch it off completely" for a couple of hours whilst you're still in the house, it could simply be that you're not "switching it off completely" for long enough for the selector memory power to drain fully and forget.. if you see what I mean.
It's an Arcam C31. It can be put into standby by pressing the button on the remote. That turns it off but leaves the on/off led orange (not off imo). I usually press the on/off switch which turns it off - however power is still getting to it as can hear the toroid humming when ear pressed against the unit.
I generally don't unplug it (or any other gear) but do turn them off as they all have on/off switches. Obviously I know they're not exactly 100% off but thought I'd pipe up in the thread as I think that's what the OP was talking about (and not talking about standby modes).
That's right, I wasn't talking about standby modes - just 'off' using the power button assuming off was off which it isn't.I'm not concerned about the power bills. Just assumed off was off. Maybe most equipment has ongoing trickle current.
Audio Advent
26-02-2016, 20:53
That's right, I wasn't talking about standby modes - just 'off' using the power button assuming off was off which it isn't.I'm not concerned about the power bills. Just assumed off was off. Maybe most equipment has ongoing trickle current.
Oh, you've got your (very nice looking) system in your sig! I didn't even look...
Audio Advent
26-02-2016, 21:07
The Arc doesn't have a power switch so is never off, only on standby.. So that's kind of your answer!
Anything without a proper physical switch to disconnect the mains will stay on. It's more common in high-end stuff but still only the minority doesn't even have a physical switch on the back.
The Darzteel looks like it has a momentary push button probably again doesn't switch off either (else it wouldn't be able to turn back on - at least the circuit reacting to the push button would need to be powered). Not sure what the "trickle charge could be though as I thought only their pre-amp had batteries.. could be just that it keeps idle currents available so that it always is at some optimum standby temp. I guess taking it's temp would be a way of telling.
My ncore amps (diy modules) can have standby modes via a push button switch but a real switch on the mains has been implemented instead.
Vampire Mode (never actually Off) Is imo Lame. Don't buy gear that does that.
Stable memories are cheap and easy to design in.
Silly Tight twit makers could easily fit some to preclude power off settings losses.
Not like there's a herd of Tubes involved that would need rebiasing when repeatedly power cycled.. is it?
I use a power bar to turn things on and off... even adds a wee bit of surge protection.. Unlikely, but Brochure babble being what it is.
Audio Advent
27-02-2016, 17:32
Vampire Mode (never actually Off) Is imo Lame. Don't buy gear that does that.
Stable memories are cheap and easy to design in.
Silly Tight twit makers could easily fit some to preclude power off settings losses.
Not like there's a herd of Tubes involved that would need rebiasing when repeatedly power cycled.. is it?
I use a power bar to turn things on and off... even adds a wee bit of surge protection.. Unlikely, but Brochure babble being what it is.
I have the idea that makers do it to ensure a stable sound signature - no warming up period, especially for valves. I think they don't want to take the risk of daft customers not understanding the nature of products they buy and therefore getting negative reviews.
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