Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

A40 power use
A40 power use
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old Yesterday, 01:25 PM   #1
aagas is offline aagas
diyAudio Member
 
Join Date: Jul 2013
Default A40 power use

I have a pair A40 stereo amplifiers each bridged to run in mono. Each drive a single DIY speaker.

I have had these amps for decades and had to replace a few parts along the way.
They still sound WONDERFUL.

I have usually just left them turned on 24/7 365 days a year.

So two questions:
(1) Do I understand correctly this circuit would draw the same amount of electricity at rest as when actually playing music?

(2) How much electricity do these 55 lb amps actually use in a year?
Old definition of an audiophile: A guy whose stereo costs more than his car.

Just wondering if I've already spent my future grandchildren's college fund on these beloved amps?

My wife keeps asking me about the electric bill ;-)
  Reply With Quote
Old Yesterday, 01:54 PM   #2
Mark Johnson is online now Mark Johnson  United States
diyAudio Member
 
Mark Johnson's Avatar
 
Join Date: May 2011
Location: Silicon Valley
A40 power use
  Reply With Quote
Old Yesterday, 02:05 PM   #3
jameshillj is offline jameshillj  Australia
diyAudio Member
 
Join Date: Feb 2005
Location: Melbourne
From memory, I think my A40 (stereo) drew about 100W/channel (but it could have been more than this too) - so using the 2 amps, this would be about 400W/hr for both amps.

I remember being pleased that my F5, even biased to a high current, consumed less power and that's about 70w per channel.

And yes, they are class A amplifiers and draw this amount of power all the time - there isn't any real reason to not turn the amps off when not in use as they only take about 30 minutes to settle down from cold.

If your electricity prices are anything like ours here (about AUD $0.28/kwh), then leaving both amps on 24/7 will soon add up to about a grand per year, if my arithmetic is correct. Hopefully, your power cost is a lot more reasonable ....
  Reply With Quote
Old Yesterday, 03:12 PM   #4
aagas is offline aagas
diyAudio Member
 
Join Date: Jul 2013
@jameshillj

Thanks. Let me see if I've got this right...

The A40 output = 40W/channel, so you may have it spot on that they draw 100W/channel to produce that.

Draw per channel in KW ........................... 0.1
Number of channels ................................. 4.0
Power draw/hr in KW ............................... 0.4
Hours per year (24 x 365.25) ....... x 8766.0
------------------------------------------------------------
KW/Year ............................................ 3506.4
Cost/KWH ............................................ x 0.21 USD
------------------------------------------------------------
Power cost/yr TOTAL ........................ 736.34 USD

A lot, but not as much as I feared.
  Reply With Quote
Old Yesterday, 08:58 PM   #5
PRR is offline PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
The electric cost is enough to justify Mark's hint to buy a Kill-A-Watt.

This reports power use, and also KHW used over time (and with programming, dollars).

Aside from audio, you can check refrigerators, the rated power of LED lighting. I got a "refurbished" microwave oven and the power consumption was way higher than rated (it did cook real fast for 2 years but died this week.)
  Reply With Quote
Old Yesterday, 09:00 PM   #6
aagas is offline aagas
diyAudio Member
 
Join Date: Jul 2013
Mark / PRR -- Much appreciated.
  Reply With Quote

Reply


A40 power useHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What 3VA power transformer meets Energy Star / IEC 62301 sub-1W vampire power spec? Mark Johnson Power Supplies 24 12th March 2017 03:18 PM
Snail Power CA18 Professional Power Amplifier,Blown Fuse & Power Transistors shorted Peter Qiu Solid State 1 10th December 2016 01:01 PM
Advantages of Power Cords with braided Shield for high Power Solid State Power Amps tiefbassuebertr Solid State 57 27th July 2015 04:56 PM
Power Cord SOCKET for Power Amp Main Con. REWIREABLE-Ultimate Quality and Standart tiefbassuebertr Solid State 7 8th February 2011 05:34 PM
power output calculations, rated power and required power output metebalci Tubes / Valves 7 22nd February 2004 06:49 PM


New To Site? Need Help?

All times are GMT. The time now is 06:36 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki