Power Consumption an Idiot's Guide to HI FI

[Trevor Whittle]

Dear Clever People

 

What does it cost, in dollars,  to run a pre amp, 300w power amp, running at very low background music volume (jazz/classical - not "doof""doof"  which  guess consumes more power) per hour?

 

And,I forgot,   a tuner for classic FM,PBS and ABC Jazz.

 

TIA (thanks in advance

 

" Man who has just received electricity bill"

 

<Image for illustrative purposes only, and may not reflect reality of poster.

 

 

 

 

 

 

[Guest thathifiguy]

Can't imagine it would cost much, unless that 300 watt power amp is pure Class A

 

I would generalise that most "normal" listening would be between 1 - 10 watts output unless you like rock concert levels.

[andyr]

44 minutes ago, helotoby said:

 

Dear Clever People

 

What does it cost, in dollars,  to run a pre amp, 300w power amp, running at very low background music volume (jazz/classical - not "doof""doof"  which  guess consumes more power) per hour?

 

And I forgot, a tuner for classic FM, PBS and ABC Jazz.

 

 

Let's start with the power amp - which, presumably, is 300w per channel.  IE. at max output (just before clipping) it outputs 300w in each channel - so 600w in total.

 

Given you said it runs at very low background music volume (jazz/classical - not "doof""doof"), as Tarkan pointed out ... it's probably outputting only 5w per channel - so 10w in total.

 

Assuming it's a Class AB amp, I would think - at worst - it would be consuming 20w from the mains socket.

 

I'd add another 20w each for the preamp & tuner - which means your system is consuming the same amount of power that a 60w (incandescent!) lightbulb does.

 

Multiply by your electricity supplier's KWHr price - and divide by 1000 - and you have your hourly cost.

 

SFA, I would suggest!    (Much less than your fridge!)

 

Andy

Edited February 29, 2020 by andyr

[JukKluk2]

1 hour ago, andyr said:

 

Let's start with the power amp - which, presumably, is 300w per channel.  IE. at max output (just before clipping) it outputs 300w in each channel - so 600w in total.

 

Given you said it runs at very low background music volume (jazz/classical - not "doof""doof"), as Tarkan pointed out ... it's probably outputting only 5w per channel - so 10w in total.

 

Assuming it's a Class AB amp, I would think - at worst - it would be consuming 20w from the mains socket.

 

I'd add another 20w each for the preamp & tuner - which means your system is consuming the same amount of power that a 60w (incandescent!) lightbulb does.

 

Multiply by your electricity supplier's KWHr price - and divide by 1000 - and you have your hourly cost.

 

SFA, I would suggest!    (Much less than your fridge!)

 

Andy

Do you mind if I show this to my wife? 

[betty boop]

max consumption is usually stamped on back...yep its max and can and will likely happen...speaker and load dependant  doesnt mean be sucking that power 24/7 so hopefully not pushing the power bill... might need to grab some solar as i did ...atleast takes care of day time power the amps suck...  

[andyr]

56 minutes ago, JukKluk2 said:

Do you mind if I show this to my wife? 

 

As long as she's not a postgraduate physicist or mathematician!    (Who might be able to find holes in my exposition.  )

 

Andy

 

[Ittaku]

It depends entirely on your equipment. As Andy has said, if they're class A amps it could be wildly different than say class D amplification which is exceptionally efficient. My equipment, for example, uses 1kW at idle and even when played at its loudest it uses almost no more power because of its design. However if I switch to my efficient equipment, it uses 50W maximum and about 10W at idle.

[JukKluk2]

10 minutes ago, andyr said:

 

As long as she's not a postgraduate physicist or mathematician!    (Who might be able to find holes in my exposition.  )

 

Andy

 

Aren't they all when the need arises?

[Ittaku]

12 minutes ago, JukKluk2 said:

Aren't they all when the need arises?

My wife's an engineer with a maths major.

[agentorange2]

3 hours ago, helotoby said:

Dear Clever People

 

What does it cost, in dollars,  to run a pre amp, 300w power amp, running at very low background music volume (jazz/classical - not "doof""doof"  which  guess consumes more power) per hour?

 

And,I forgot,   a tuner for classic FM,PBS and ABC Jazz.

 

TIA (thanks in advance

 

" Man who has just received electricity bill"

 

 

The hydro crop would be using more power than your gear , maybe time to go solar.

[betty boop]

simple thing to remember is Law of Conservation of Energy, that states that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another...

 

so if sucking down the watts ...you are only going to get them from one source ... the power socket...but yes depending on the amp you could be burning off most of the power in form of heat...eg with class A amps... not to say Class D cant be innefiient too.. have come across plenty which run pretty hot dissipating and wasting evergy as heat...

 

class A amps can be 25% efficient upto 50%...class AB a theoretical 78.5% efficient depending on amount of class A bias could be closer to 60%-75%. Class D while theoretical 100% is more like 90% or so...

[andyr]

2 hours ago, JukKluk2 said:

Aren't they all when the need arises?

 

2 hours ago, agentorange2 said:

The hydro crop would be using more power than your gear , maybe time to go solar.

 

Both gold!! 

 

Andy

 

[MattyW]

Really depends on the gear as others have said. 

 

My system tends to be on whenever I'm home so about 6pm to 12pm weekdays and 8am to 12pm weekends. My tube preamp and 6WPC power amp are class A, and the 100WPC power amp on the woofers is class AB. My last power bill was only $180 and we've used the air conditioning this summer.

 

Part of that is the design. The Linear Tube Audio MicroZOTL 3 I use as a preamp  uses very little power as it's not a traditional tube design whereas the Wavebourn Edelweiss-3 is only 6WPC and really doesn't push the tubes hard at all.

 

This can be seen in that the system makes no meaningful impact on room temperature. This was by design this time around. High efficiency speakers and low wattage amps seems the best compromise to achieve great sound in the hot and humid Brisbane environment.

[rantan]

........

Edited February 29, 2020 by rantan

[Steffen]

You can buy a power meter for 30-odd bucks or so, it’ll give you instantaneous and cumulative readings. My guess is that it would  take your Hi-Fi system about a year of energy consumption to reach the cost of the power meter. 

Edited February 29, 2020 by Steffen

[muon*]

14 minutes ago, MattyW said:

Really depends on the gear as others have said. 

 

My system tends to be on whenever I'm home so about 6pm to 12pm weekdays and 8am to 12pm weekends. My tube preamp and 6WPC power amp are class A, and the 100WPC power amp on the woofers is class AB. My last power bill was only $180 and we've used the air conditioning this summer.

 

Part of that is the design. The Linear Tube Audio MicroZOTL 3 I use as a preamp  uses very little power as it's not a traditional tube design whereas the Wavebourn Edelweiss-3 is only 6WPC and really doesn't push the tubes hard at all.

 

This can be seen in that the system makes no meaningful impact on room temperature. This was by design this time around. High efficiency speakers and low wattage amps seems the best compromise to achieve great sound in the hot and humid Brisbane environment.

Damn! ours was $500 and we don't use air con.

[rantan]

8 hours ago, helotoby said:

What does it cost, in dollars,  to run a pre amp, 300w power amp, running at very low background music volume (jazz/classical - not "doof""doof"  which  guess consumes more power) per hour?

2/3 of fcuk all. Why are you concerned?

[MattyW]

24 minutes ago, muon* said:

Damn! ours was $500 and we don't use air con.

This system uses way less power than the darTZeel NHB108B copy based system did, or the 45WPC Oldchen K3 which was class AB..... Course we only use aircon in the day and we've solar. 

 

we've LED lights everywhere though rather than use multiple ceiling downlights we tend to rely on lamps with 3-5W LED bulbs instead.  Fridge bulbs in the bedroom lamps.....

Edited February 29, 2020 by MattyW

[muon*]

1 minute ago, MattyW said:

This system uses way less power than the darTZeel NHB108B copy based system did, or the 45WPC Oldchen K3 which was class AB..... Course we only use aircon in the day and we've solar. 

Ah, the solar explains things.

 

I think when I took a reading of my system with my 20w Triode strapped AB PP amp, Sansui SR-838 and 6SL7 Ear circuit phono stage it used around 160 watts during play.

[Hazzzy]

6 hours ago, agentorange2 said:

The hydro crop would be using more power than your gear

But would pay the bills for you....So I have heard.

Highly not recommended as your house may burn and your insurance will be useless...So I have heard.

My technical take is my old meter spins faster in class A and slows down a bit in AB.

Edited February 29, 2020 by Hazzzy

[Addicted to music]

https://www.ebay.com.au/itm/AU-Plug-Power-Energy-Consumption-Watt-Meter-Electricity-Usage-Monitor-Equipment/362740900053?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D20160908110712%26meid%3D3e73fd6546c443f889e83123989a3736%26pid%3D100677%26rk%3D2%26rkt%3D30%26mehot%3Dnone%26sd%3D153523967671%26itm%3D362740900053%26pmt%3D1%26noa%3D0%26pg%3D2386202%26algv%3DSimplAMLv5PairwiseWeb&_trksid=p2386202.c100677.m4598

 

 

Knock yourself out.....

Edited March 1, 2020 by Addicted to music

[andyr]

1 hour ago, rantan said:

2/3 of fcuk all. Why are you concerned?

 

Maybe because he's heard on "social media" that "it's good to be green"!

 

Andy

 

[Fetfan]

They are green and green.

Edited February 29, 2020 by Fetfan

[Addicted to music]

14 hours ago, Fetfan said:

They are green and green.

Green is when you grow grass from rain water and put PV panels on your roof.....

 

I think he’s more worried about running costs 

 

[Mat-with-one-t]

On 29/02/2020 at 8:08 PM, MattyW said:

This system uses way less power than the darTZeel NHB108B copy based system did, or the 45WPC Oldchen K3 which was class AB..... Course we only use aircon in the day and we've solar. 

 

we've LED lights everywhere though rather than use multiple ceiling downlights we tend to rely on lamps with 3-5W LED bulbs instead.  Fridge bulbs in the bedroom lamps.....

Careful mate.  Fridge bulbs in the bedroom can lead to frigidity.....