Almost everything electrical in my house boasts its A+Energy Star rating except for the audio systems. If I take a typical big-box system: the JVC NX-F7 offer an SPL of 76db. Simply changing the speakers would reduce the power consumption at any given listening level.
Energy prices have doubled in my country. Throwing gazillions of watts at tiny speakers doesn't seem to be the best way forward. It seems bizarre that, when cranked-up, my sub consumes more power than every light-bulb in the house.
Has anybody considered efficiency as a primary design concern?
Hopefully, I want to build something in the Spring.
Any ideas?
Energy prices have doubled in my country. Throwing gazillions of watts at tiny speakers doesn't seem to be the best way forward. It seems bizarre that, when cranked-up, my sub consumes more power than every light-bulb in the house.
Has anybody considered efficiency as a primary design concern?
Hopefully, I want to build something in the Spring.
Any ideas?
Hofmann's Iron Law irrevocably ties efficiency to box size and LF extension, so accepting a design that either has less bass or uses bigger speaker enclosures allows the designer to have higher efficiency.
The extreme of this is horn loaded systems which are often operated by amps with single digit power ratings.
The extreme of this is horn loaded systems which are often operated by amps with single digit power ratings.
Start with a Class D amp. That will use less power. That is probably the biggest opportunity to reduce energy consumption!
I built high efficiency speakers. I used pro audio/ PA speaker drivers. They will require large speaker cabinets! Actual efficiency of my system is ~92dB after adding pads to kill the noise. Beware of the noise!
High efficiency speakers will do more with less power, but my 107dB horns had a horrific hissing! The hissing is caused by the amp. (No arguments please! I KNOW it is the amp.) I added a 30ohm resistor in line to kill the noise. It is a bit extreme, but completely necessary!
Amps are noisy. I have Emotiva's XPA amp with H-bridge. It is quieter than a transformer based class A/B design, but it has a noise floor as all amps do.
If you want to build a high efficiency system, I would recommend starting with the amp. I did it the other way around and got a bit discouraged. Find the best Class D amp you can. Most have rated noise specs similar to a good A/B amp from what I have seen, but there are standouts. And it's still relatively new tech in the hifi world. Audioholics measured one with a ~120dB signal to noise ratio. I would start with something like that.
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Unless you listen to dubstep all day long at high volume, the actual power consumption is probably quite low. Music has a wide dynamic range; when an amp is near clipping on peaks, the average power is usually just a 1/10 of maximum, so under more normal listening conditions it'll be much lower. Maybe you have much more power than you really need; for years I ran the subs from amps capable of 100 to 400 wpc, but eventually realized that a 40 wpc amp on the subwoofers was enough for bass I could feel. Setting subwoofer levels correctly with test tones and SPL meter might have had something to do with that.
If you're concerned about power consumption, use a power meter to see what you're really using. Kill-A-Watt is what I have, but it looks like there isn't a UK/EU version. Here's something like it:
https://www.amazon.co.uk/Maxcio-Consumption-Monitoring-Overload-Analyzer/dp/B085M6GL2R/
Some smart sockets also do energy monitoring, plus you could use it to shut off your whole system and eliminate the vampire loads, and turn it on with voice commands:
https://www.amazon.co.uk/TP-Link-Monitoring-SmartThings-Wireless-KP115/dp/B08LZWBTR6/
For an efficient minimal system, start with a class-D amp module. My DAC uses more power than the Tripath TA2024 amp. It's an under-ten-dollar board mounted in a recycled modem case and powered from a thrift store Wii power brick.
If you want a higher quality board than no-name clones, there's Sure Electronics. The TA2024 amp board I got from them came complete with RCA and power cables and even binding posts.
https://www.ebay.com/str/surehifi
If you're concerned about power consumption, use a power meter to see what you're really using. Kill-A-Watt is what I have, but it looks like there isn't a UK/EU version. Here's something like it:
https://www.amazon.co.uk/Maxcio-Consumption-Monitoring-Overload-Analyzer/dp/B085M6GL2R/
Some smart sockets also do energy monitoring, plus you could use it to shut off your whole system and eliminate the vampire loads, and turn it on with voice commands:
https://www.amazon.co.uk/TP-Link-Monitoring-SmartThings-Wireless-KP115/dp/B08LZWBTR6/
For an efficient minimal system, start with a class-D amp module. My DAC uses more power than the Tripath TA2024 amp. It's an under-ten-dollar board mounted in a recycled modem case and powered from a thrift store Wii power brick.
If you want a higher quality board than no-name clones, there's Sure Electronics. The TA2024 amp board I got from them came complete with RCA and power cables and even binding posts.
https://www.ebay.com/str/surehifi
The consumption at normal levels should be less than 0.05 kW / hour, about 20 hours worth for a single 'unit' of power , for a complete system, amp, player / computer and all.
At the current price of 34 pence, you are spending 1.7 pence per hour on audio.
Not really worth the hassle of modifying a system, Class D has its advantages, but still, you will save a couple of quid a month at most.
The higher energy wastage occurs in heating losses, the USA has insisted on energy saving measures and insulation over the years, standards are increasingly strict.
You can read up about those, and lower your energy bills.
Start by changing over to LED lighting, and energy efficient parts in the HVAC, which in UK may not be as evolved as in the USA.
Double and triple glazed windows save a lot of energy, they can be expensive.
Insulation on the roof, at the level under the attic, that is also an area for improvement, wall insulation as well.
At the current price of 34 pence, you are spending 1.7 pence per hour on audio.
Not really worth the hassle of modifying a system, Class D has its advantages, but still, you will save a couple of quid a month at most.
The higher energy wastage occurs in heating losses, the USA has insisted on energy saving measures and insulation over the years, standards are increasingly strict.
You can read up about those, and lower your energy bills.
Start by changing over to LED lighting, and energy efficient parts in the HVAC, which in UK may not be as evolved as in the USA.
Double and triple glazed windows save a lot of energy, they can be expensive.
Insulation on the roof, at the level under the attic, that is also an area for improvement, wall insulation as well.
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Small tpa 2118 amp provides 20 wpc and will average less then 10w from line while being played loud.