Mosfet Headphone Amp - diyAudio
Go Back   Home > Forums > Amplifiers > Headphone Systems

Headphone Systems Everything to do with Headphones

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 3rd March 2011, 08:05 PM   #1
diyAudio Member
 
apexaudio's Avatar
 
Join Date: Feb 2010
Location: Serbia
Default Mosfet Headphone Amp

Headphone Amplifier for 32 ohm or more with TO92 mosfets, 100uF can be shorted if there is no DC offset on output (drains).
Attached Images
File Type: jpg APEX Headphone Amp.jpg (109.8 KB, 1847 views)

Last edited by apexaudio; 3rd March 2011 at 08:25 PM.
  Reply With Quote
Old 7th March 2011, 11:21 PM   #2
diyAudio Member
 
apexaudio's Avatar
 
Join Date: Feb 2010
Location: Serbia
DIP4 mosfets IRFD014 and IRFD9014 can be use intead BS170 and BS250
  Reply With Quote
Old 21st March 2011, 03:19 PM   #3
diyAudio Member
 
Join Date: Jan 2010
Good looking Apex, you have any PCB designs for this Maybe, thanks for sharing I'm building a Preamp these days and this would work as the HP amp on it, I already built ur A Class PSU its Brilliant Ill post pictures on that thread
  Reply With Quote
Old 22nd March 2011, 10:08 PM   #4
diyAudio Member
 
apexaudio's Avatar
 
Join Date: Feb 2010
Location: Serbia
Quote:
Originally Posted by zeraphine View Post
Good looking Apex, you have any PCB designs for this Maybe, thanks for sharing I'm building a Preamp these days and this would work as the HP amp on it, I already built ur A Class PSU its Brilliant Ill post pictures on that thread
I must design new pcb, old pcb is mono.
Regards
  Reply With Quote
Old 25th July 2011, 03:43 PM   #5
diyAudio Member
 
Join Date: Mar 2011
Can i use another mosfets, like IRF510 and 9510? Or another power mosfet?
  Reply With Quote
Old 25th July 2011, 03:53 PM   #6
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
lots of devices can be used, including "power" mosfests, but you should try to keep the Q size somewhat porportional to the circuit requirements to avoid excess parasitic C

4 A rated Q for 100 mA is already a little overboard
  Reply With Quote
Old 31st January 2012, 03:57 PM   #7
diyAudio Member
 
apexaudio's Avatar
 
Join Date: Feb 2010
Location: Serbia
Quote:
Originally Posted by jcx View Post
lots of devices can be used, including "power" mosfests, but you should try to keep the Q size somewhat porportional to the circuit requirements to avoid excess parasitic C

4 A rated Q for 100 mA is already a little overboard
BJTs also can be use instead MOSFETs

Last edited by apexaudio; 31st January 2012 at 04:04 PM.
  Reply With Quote
Old 31st January 2012, 08:54 PM   #8
diyAudio Member
 
Join Date: Nov 2004
Location: Germany
Looking at the schematic, it uses the old trick of driving the buffer stage via the opamp supplies. Isn't that considered somewhat problematic when it comes to stability?
  Reply With Quote
Old 14th February 2012, 05:09 AM   #9
routhun is offline routhun  United States
diyAudio Member
 
Join Date: Mar 2005
Location: Sunnyvale
Not only the stability, I have a question about the distortion. The basic principle of this topology is the current drawn by opAmp is proportional to the input signal, and the resistors in series of the opAmp power supply generate proportional bias for the output devices which drives the load.

By my question is, how accurate is the power drawn by the opAmp proportional to the input signal? If it is not accurate, then output drive is not proportional to input signal means heavy distortion?

Thanks,
Routhun
__________________
routhun
  Reply With Quote
Old 15th February 2012, 03:28 PM   #10
diyAudio Member
 
Join Date: Nov 2004
Location: Germany
It all is within the feedback loop, so that shouldn't be too dramatic.

The opamp must be able to tolerate 1k2 of series resistance on the supplies though, which I guess means stability will depend heavily on the type used (ye olde TL07x isn't terribly critical AFAIK). A little too many ifs and buts for my taste, but YMMV.
  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
Fault with MOSFET based headphone amp zebra100 Headphone Systems 8 7th October 2008 03:29 PM
Regulated PSU for MOSFET headphone amp zebra100 Headphone Systems 9 25th September 2008 05:59 PM
12 Volt MOSFET SE Class A Hi-Fi HeadPhone Amp lineup Headphone Systems 3 18th July 2008 01:49 AM
darlington/mosfet in emittor follower / headphone amp svokke Headphone Systems 11 8th June 2005 06:19 PM


New To Site? Need Help?

All times are GMT. The time now is 08:48 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