quick solid state amp question - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 28th October 2008, 12:06 AM   #1
gain is offline gain  United States
diyAudio Member
 
gain's Avatar
 
Join Date: Apr 2008
Default quick solid state amp question

form a component durability standpoint (especially OPS transistors), when not listing to music, is it better to:

- leave your amp in hot standby (power on no signal applied but idling)
- power it off

i always thought that it was the thermal cycles (heat up then cool down) that wore out components, so i have always left my amps on continuously. but i was talking to a stereo guy i met recently and he advised to always turn amp off because its the heat itself that kills, not the cycling between hot and cold.

which is right?
  Reply With Quote
Old 28th October 2008, 12:14 AM   #2
diyAudio Member
 
Join Date: Mar 2002
If your amp runs (idles) at a comfortable, slight, warmness then leaving it on is better. If it runs real warm or hot (you can get a whiff of warm parts) then turn it off. Amps (like lightbulbs) do tend to blow at turnon so if in doubt, leave it on.
  Reply With Quote
Old 28th October 2008, 01:30 AM   #3
gain is offline gain  United States
diyAudio Member
 
gain's Avatar
 
Join Date: Apr 2008
hey thanks for the reply. yeah it idles pretty cool when i touch the heatsinks when nothing's been playing for a while i barely feel warmth. just enough to let me know its on. in fact, i use the 3 second rule on all of my amps ... if i can't keep my fingers comfortably on the component for 3 seconds without pain, its too hot.

some may say thats overly conservative but i like my stuff to run cool enough to touch.
  Reply With Quote
Old 28th October 2008, 05:10 PM   #4
diyAudio Member
 
Nico Ras's Avatar
 
Join Date: Nov 2005
Location: East Coast of South Africa
Quote:
Originally posted by hitsware
If your amp runs (idles) at a comfortable, slight, warmness then leaving it on is better. If it runs real warm or hot (you can get a whiff of warm parts) then turn it off. Amps (like lightbulbs) do tend to blow at turnon so if in doubt, leave it on.

I agree with you that leaving an amp on it is always ready to play. My trusty 50 watt class A is hot to touch but has never been turned off in eight years. I guess it will fail one day.

Nico
  Reply With Quote
Old 29th October 2008, 05:13 AM   #5
diyAudio Member
 
Jan Dupont's Avatar
 
Join Date: Apr 2003
Location: Copenhagen, Denmark
Send a message via MSN to Jan Dupont
There is a term called "Working hours lifetime" for all components.

It may be better to leave your amp on for a short time (few hours) if you know that you will be listening again very soon, however if the design is made right, the transistors won't suffer from switching the amp On/Off when not listening.

Much worse is it for the electrolytic caps (PSU caps etc.)! These have normally only a working lifetime of 2000 hours, so by leaving your amp On all the time quickly eats up the caps lifetime.
__________________
Free Schematic and Service Manual downloads www.audio-circuit.dk, Company: www.dupont-audio.com, Joint venture: www.DupontMantra.com
  Reply With Quote
Old 29th October 2008, 11:04 AM   #6
PMA is offline PMA  Europe
diyAudio Member
 
PMA's Avatar
 
Join Date: Apr 2002
Location: Prague
Jan, 2000 hours is at maximum operating temperature, i.e. +85C or +105C, according to type used. At some 40-50C, the cap life time is much much longer.
  Reply With Quote
Old 29th October 2008, 01:48 PM   #7
CBS240 is offline CBS240  United States
diyAudio Member
 
CBS240's Avatar
 
Join Date: Aug 2005
Location: K-town
What about metal fatigue, would it be an issue particularly the bonding wires that connect the pins to the die? Hot/cold/hot/cold ect will take a toll on the wire bond strength, just like the filament in a light bulb. Incandescence bulbs tend to last longer if they are left on continuously compared to intermittent use. I saw a program once about an old firehouse light bulb that has been on for like 75 years. Nobody dares turn it off because the filament may break from temperature change and age and no one wants to be the one responsible for its death. They just don't make 'em like they use to anymore.
__________________
All the trouble I've ever been in started out as fun......
  Reply With Quote
Old 29th October 2008, 02:02 PM   #8
diyAudio Member
 
Jan Dupont's Avatar
 
Join Date: Apr 2003
Location: Copenhagen, Denmark
Send a message via MSN to Jan Dupont
Pavel
You are absolutely right
I was not really awake when I replied to this thread
__________________
Free Schematic and Service Manual downloads www.audio-circuit.dk, Company: www.dupont-audio.com, Joint venture: www.DupontMantra.com
  Reply With Quote
Old 29th October 2008, 02:31 PM   #9
h_a is offline h_a  Europe
diyAudio Member
 
h_a's Avatar
 
Join Date: Sep 2006
Location: Graz, Austria
It depends a bit on the amp.

ClassB-amp: no thermal cycling to speak of when switching on/off; only thermal cycling is caused by listening to music. Leaving it on all the time will hurt your power supply caps (as ACD already wrote).

(By the way there's the old rule for temperature: every 10C temperature increase cut lifetime of the part in half. So a 85C cap with 2000 hours lifetime translate into 32000 hours at 45C - in about 4 years permanent on the caps are outside their specified lifetime.)

ClassA-amp: thermal cycling due to Class A; however there's not much benefit again for leaving it on as the caps have to endure high ripple current and higher ambient temperature. Both reduce lifetime.

In short: switch it off at least for the night.

Have fun, Hannes
  Reply With Quote
Old 29th October 2008, 05:40 PM   #10
AMV8 is offline AMV8  United Kingdom
diyAudio Member
 
Join Date: Jan 2005
Location: near london
Hi

I guess I go along with ha and ACD.

In practice I have found that the longest use I have had from a piece of equipment was from a Sony professional tv. That lasted 20 years. If you assume 2 hours per day that gives 600 hours per year ( time off for hols ) or 12,000 hours.

I have also assumed that electrolytic caps dry out slowly over the years and this is exascerbated by keeping them warm. ( find thaty electrolytics last a long time if stored in a sealed plastic bag.)

I switch equipment off at nights.

Don
  Reply With Quote

Reply


Hide 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solid state Class-A question neazoi Solid State 7 29th March 2009 10:43 PM
question ad146 solid state amp arhi45 Solid State 0 29th May 2008 06:42 PM
The Solid State Wiki - Your solid state reference guide Jason Solid State 0 25th June 2002 05:26 PM


New To Site? Need Help?

All times are GMT. The time now is 12:00 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2