I'm sorry if this isn't the best subforum, but I honestly didn't know where was better.
In general, we leave our speaker setups on but turn the sources off (computer, tvs, etc) at the end of the day. For example, my main living room setup is an nvidia shield feeding a minidsp going to two tpa3118 lepais (until I can afford much better amps) to my WAWs.
My wife asked me how much electricity gets used when the amps are on but nothing coming from source and I was ashamed to have no idea. Could perhaps those with more relevant degrees help a biologist out? Thanks ahead!
In general, we leave our speaker setups on but turn the sources off (computer, tvs, etc) at the end of the day. For example, my main living room setup is an nvidia shield feeding a minidsp going to two tpa3118 lepais (until I can afford much better amps) to my WAWs.
My wife asked me how much electricity gets used when the amps are on but nothing coming from source and I was ashamed to have no idea. Could perhaps those with more relevant degrees help a biologist out? Thanks ahead!
10% ish of rated power.
Keep in mind things with a remote control like TV also consume power when off. Depending on the remote control design on gizmos they might consume the same current on or off! The power consumed drops because when off the voltage is out of phase with the current so the power drops.
That is because many remote controls switch the power after the power transformer. Same with virtually all gizmos that use wall wart power supplies.
Keep in mind things with a remote control like TV also consume power when off. Depending on the remote control design on gizmos they might consume the same current on or off! The power consumed drops because when off the voltage is out of phase with the current so the power drops.
That is because many remote controls switch the power after the power transformer. Same with virtually all gizmos that use wall wart power supplies.
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Nowadays, the power consumption, in watts (W), of a device when on standby is stated by the manufacturer.
Electrical energy consumption is measured in kilowatt hours (kWh).
One kilowatt hour is known as one unit of electrical energy, and it is the number of units you consume that you have to pay for.
So, add up all your standby watts, estimate the time for which they are being utilised and calculate your electricity units using this equation:
units = watts/1000 x hours
Electrical energy consumption is measured in kilowatt hours (kWh).
One kilowatt hour is known as one unit of electrical energy, and it is the number of units you consume that you have to pay for.
So, add up all your standby watts, estimate the time for which they are being utilised and calculate your electricity units using this equation:
units = watts/1000 x hours
Oh cool, I thought it'd be more than that!
So, is that a rule of thumb or is that an intrinsic property of class d amplification? And is it dependent at all on where you leave the volume?
I guess that also would answer the question of source. If your source is low and you have to turn the volume high on the amp, does that use the same electricity than if your source is high and you have the volume low on the amp?
So, is that a rule of thumb or is that an intrinsic property of class d amplification? And is it dependent at all on where you leave the volume?
I guess that also would answer the question of source. If your source is low and you have to turn the volume high on the amp, does that use the same electricity than if your source is high and you have the volume low on the amp?
If you buy a Killawatt meter you can test all your electronics for power consumption. Some libraries have them and will let you check one out...otherwise you can buy one for about $20. Most items you just plug into it for a minute, but refrigeradors need to be left plugged in over night due to usage affecting results.
Funny you should ask…
In a past life I designed off-grid solar electric systems for a living. Always told people a Kill-A-Watt meter is the most useful gadget an off grid’r could have, and I believe every household should have one too. They are great for answering your question and also tracking down those parasitic loads that we don’t even think about.
Myself, I’ve recently retired and in the process of outfitting a travel trailer for a year on the road. I want to take a modest but good sounding speaker system with me. Upon finishing my ACA I plugged it in and while it did sound good the second thing I noticed was “man this thing gets hot!” My trusty Kill-A-Watt showed me that it was pulling just 10watts less than my tube amp, a trivial matter when plugged into the wall but disconcerting when living off solar and batteries where every watt is precious.
That revelation started me on the path to Class D amps and RPi based systems, both of which can be powered directly from my onboard 12V battery.
In a past life I designed off-grid solar electric systems for a living. Always told people a Kill-A-Watt meter is the most useful gadget an off grid’r could have, and I believe every household should have one too. They are great for answering your question and also tracking down those parasitic loads that we don’t even think about.
Myself, I’ve recently retired and in the process of outfitting a travel trailer for a year on the road. I want to take a modest but good sounding speaker system with me. Upon finishing my ACA I plugged it in and while it did sound good the second thing I noticed was “man this thing gets hot!” My trusty Kill-A-Watt showed me that it was pulling just 10watts less than my tube amp, a trivial matter when plugged into the wall but disconcerting when living off solar and batteries where every watt is precious.
That revelation started me on the path to Class D amps and RPi based systems, both of which can be powered directly from my onboard 12V battery.
Look for systems or integrated circuit amps that are designed to be used in battery powered devices. They are designed to have super low idle or standby current, and will often go into a very low power standby mode when not in use.
A lot of class D ICs fit that description, including the TPA3118. Its datasheet says it draws 32 mA from a 24V supply at idle. That would be 0.77W. You're likely powering it from 19V. Current at 19V drops to 27 mA, giving 0.51W.
Each of your TPA3118 draws about half a watt with no signal.
(I was on the design team for the TPA3116, and designed some of its circuits, notably the ramp generator and the dead-time controller for the output stage.)
A lot of class D ICs fit that description, including the TPA3118. Its datasheet says it draws 32 mA from a 24V supply at idle. That would be 0.77W. You're likely powering it from 19V. Current at 19V drops to 27 mA, giving 0.51W.
Each of your TPA3118 draws about half a watt with no signal.
(I was on the design team for the TPA3116, and designed some of its circuits, notably the ramp generator and the dead-time controller for the output stage.)
I know I stated in my last post that each amp only draws half a watt, but here's really no reason to leave your speaker systems on. They are switching systems, and unlike AB amplifiers, you are not waiting on the bias to settle. Start-up time is about 100 milli-seconds.
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