Hafler 9130/Pro1200 circuit differences? - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 26th May 2008, 03:46 AM   #1
reiver is offline reiver  United States
diyAudio Member
Join Date: May 2008
Location: CT
Default Hafler 9130/Pro1200 circuit differences?

A question for fellow Hafler owners.

I'm modifying my Hafler 9130 amplifier, and have been comparing the schematics between it and the Pro1200. They both appear to be identical except (except for one resistor, R21) and the separate circuit that looks like the power supply to drive the front end.

I'm no expert on circuit design, can anyone suggest the difference between these two circuits, I assume the 9130 version is simply a "better" design and the Pro1200 version simplified to lower costs?


see attached
Attached Images
File Type: gif comparison.gif (70.5 KB, 118 views)
  Reply With Quote
Old 26th May 2008, 04:29 PM   #2
reiver is offline reiver  United States
diyAudio Member
Join Date: May 2008
Location: CT
Default re:

I figured it out.

The "left" side of the circuit is the thermal circuit which shuts down the amp when overheating. The new "right" side is the soft on/off circuit which came out on the 9130, but not on the Pro1200.
  Reply With Quote


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
WTB Hafler SE-120 or PRO 1200 or 9130 Circuit Board Dick West Swap Meet 5 7th February 2011 10:13 PM
Help with Hafler Pro1200 sl 15 Solid State 1 20th April 2009 05:01 PM
Hafler Pro1200 MOSFET subs IFixAudio Parts 1 5th April 2009 04:35 PM
2SK1056 MOSFET for Hafler PRO1200 IFixAudio Solid State 0 27th March 2009 04:14 AM

New To Site? Need Help?

All times are GMT. The time now is 04:26 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2