Noisy Amp - Page 2 - 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 15th January 2009, 07:21 AM   #11
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Quote:
but this is not a short burst of sound, it sound more like an aircraft crashing! (not joking), and lasts about 5-6 seconds
Did it start doing this all of a sudden, or did this errata increase
gradually (over the months/years)??
OS
  Reply With Quote
Old 15th January 2009, 11:09 AM   #12
vento is offline vento  United Kingdom
diyAudio Member
 
Join Date: Oct 2008
Quote:
Originally posted by ostripper


Did it start doing this all of a sudden, or did this errata increase
gradually (over the months/years)??
OS
Hi ostripper,
Can’t answer that one as it had the fault when I bought it, and was unaware of the problem.

Had a look on the net for circuit diagram, and ‘Hen’s Teeth’ spring to mind.
  Reply With Quote
Old 15th January 2009, 11:20 PM   #13
diyAudio Member
 
nigelwright7557's Avatar
 
Join Date: Apr 2008
Location: Carlisle, England
Quote:
Originally posted by lineup
This is quite normal.
And nothing to be very afraid of.
At power off the big electrolytic capacitors take some short time to dis-charge.

A way to avoid this would be to use an output relay.
This relay should immidiately disconnect speakers when OFF switch pressed.
This is probably how most commercial amplifiers do it.

Along with a delay to connect speakers at POWER ON.
To let everything get charged, settled and stable, before connect the speakers.
This will avoid any 'pop' sounds at power on.

I use a microcontroller and a relay to do this.
The micro gives a 3 second delay to the relay on power up.
It also looks for looks for DC output (fault state) and disconnects the speakers if a fault state is found.
__________________
PCBCAD50 software. http://www.murtonpikesystems.co.uk
  Reply With Quote
Old 16th January 2009, 08:45 PM   #14
diyAudio Member
 
Nico Ras's Avatar
 
Join Date: Nov 2005
Location: East Coast of South Africa
Quote:
Originally posted by lineup


I is more serious than I first thought.
5-6 seconds ... hmmm
If you can provide more info, somebody may figure out what is the trouble.
At least we now know what amplifier: Music Fidelity E10
Hi Line-up, I was joking with my comment of course.


I came across a problem many years ago on a guitar amp which may or may not be similar, but what happened was that a little while after turning power off a whistling sound came from the speaker and died down as the capacitors discharged.

The problem lay in one rail discharging quicker than the other and the amplifier became unstable as it got to some threshold voltage.

The reason for the unequal discharge was that all pilot lights were connected only to one rail of the power supply.

Regards

Nico
  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
Noisy ADC 5th element Digital Line Level 6 30th August 2009 10:29 PM
Noisy NAD 705 squirrel69 Solid State 6 7th April 2006 01:37 AM
noisy noisy noisy noisy noisy tube dsavitsk Tubes / Valves 50 20th February 2006 04:07 PM
help on P1.7 (Noisy) pamaz Pass Labs 9 26th August 2004 02:21 PM
How can i use a noisy PSU ? Garbz Solid State 5 3rd January 2004 12:15 AM


New To Site? Need Help?

All times are GMT. The time now is 08:02 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