heat sinks for resistors - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 9th November 2007, 04:51 PM   #1
diyAudio Member
 
Moondog55's Avatar
 
Join Date: Jun 2007
Location: Norlane; Geelong: Victoria: Australia
Default heat sinks for resistors

having seen the "Mission" post and having also taken apart quite a few older cross-overs when making repairs and salvaging parts from older boxes I have a query.
Would it be an advantage to mount the cross-over resistors on individual heat-sinks??
I have just picked up some industrial shelving support from a junk pile, ot is perforated and by cutting small lengths of it and using silicone as the glue i could attach the ceramic resistors in such a way as to cool said resistor more effectively.
Is there any real advantage??
__________________
QUOTE" The more I know, the more I know, I know (insert maniacal laugh >here<) NOTHING"
  Reply With Quote
Old 9th November 2007, 05:27 PM   #2
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
These types of resistors are designed not to need a heatsink - the body can dissipate the rated power. The problem arises simply because of a combination of any or all of:

- too much voltage applied (exceed power rating), abuse from clipping etc
- inadequate airflow given to implementation
- underspec power rating to save a few pennies
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 9th November 2007, 10:09 PM   #3
diyAudio Member
 
Moondog55's Avatar
 
Join Date: Jun 2007
Location: Norlane; Geelong: Victoria: Australia
It is just that I have seen so many instances where the resistor has burnt the substrate the have been attached to, either foam as in the case of my IMF's or the cheap fibre of some of the printed circuit boards.
I know in amplifier applications ceramic resistors are always mounted proud of the base/ circuit board to allow airflow but in all the crossover applications I have seen they are glued hard against the board.
It seemed like a no cost possible benefit
__________________
QUOTE" The more I know, the more I know, I know (insert maniacal laugh >here<) NOTHING"
  Reply With Quote
Old 10th November 2007, 12:13 AM   #4
diyAudio Member
 
sdclc126's Avatar
 
Join Date: Jan 2005
Location: San Diego, CA
You can just suspend the resistors in free air above the board - just solder them in with short leads and the wire itself will hold them up. No need to rig up anything underneath it, unless you just want to glue in a small piece of metal or other heat resistant material for looks and/or extra stability.
__________________
Soft Dome
  Reply With Quote
Old 11th November 2007, 04:35 AM   #5
D OB G is offline D OB G  Australia
diyAudio Member
 
Join Date: May 2007
I was under the impression that the resistance changes with significant change in temperature, and that the signal undergoes distortion above a particular temperature for that component.
i.e. that a ceramic reisistor shouldn't get noticably hot?
Metal Oxide resistors (high cost, but good sound) can be heat sinked to handle 100 plus watts (i.e not get noticably hot under normal use), or mutiple higher valued ceramic resitors can be paralleled as necessary.

David
__________________
D OB G
  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
FS: Heat sinks gengis Swap Meet 8 17th March 2006 02:27 AM
Heat Sinks serengetiplains Parts 3 3rd January 2006 07:41 AM
where do you get your heat sinks ? percy Chip Amps 12 16th August 2005 08:00 PM
heat sinks D3 Pass Labs 9 29th December 2003 08:19 AM


New To Site? Need Help?

All times are GMT. The time now is 08:28 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