Results 1 to 3 of 3

Thread: Some problems about the audio amplifier circuit

  1. #1
    Junior Member
    Join Date
    Dec 2016
    Location
    hongkong
    Posts
    9

    Some problems about the audio amplifier circuit

    Hello guys! I am trying to make an LM301 audio amplifier circuit.Just started with some audio amp and trying to wrap my head around it all. I was just curious if you could expand on a couple of things quickly. They are probably really basic so feel free direct me anywhere else. First how do you know what value capacitors you should be using? Why does the Capacitor filter the hig frequency rather then an actual High pass filter?

  2. #2
    Senior Member Doctor_Electron's Avatar
    Join Date
    May 2003
    Location
    California Central Coast, USA
    Posts
    317

    I would start with watching this tutorial on operational amps

    Quote Originally Posted by hyuna View Post
    Hello guys! I am trying to make an LM301 audio amplifier circuit.Just started with some audio amp and trying to wrap my head around it all. I was just curious if you could expand on a couple of things quickly. They are probably really basic so feel free direct me anywhere else. First how do you know what value capacitors you should be using? Why does the Capacitor filter the hig frequency rather then an actual High pass filter?
    Op amps aren't particularly hard to design with, but you need to start out by leaning the rudiments. This is a good starting point:
    https://www.youtube.com/watch?v=7FYHt5XviKc&t=34s
    "Why don't you Mine your own Bismuth, so you won't be mining mine?"

  3. #3
    Senior Member
    Join Date
    Apr 2003
    Location
    Australia
    Posts
    7,455
    Quote Originally Posted by hyuna View Post
    Hello guys! I am trying to make an LM301 audio amplifier circuit.Just started with some audio amp and trying to wrap my head around it all. I was just curious if you could expand on a couple of things quickly. They are probably really basic so feel free direct me anywhere else. First how do you know what value capacitors you should be using? Why does the Capacitor filter the hig frequency rather then an actual High pass filter?
    Not sure why you are trying to do this ?

    Have a look at Douglas Self’s website.

    If you go to the Texas instructions website there are some great told look.

    If your talking about the compensation capacitor go check the original data sheet. It depends on the open loop gain bandwidth product and the closed loop gain you want.

    With coupling capacitors aim for 470uF non polarised electrolytic.

    Generally speaker it’s difficult to improve on the static performance on a chip Opamp because they can trim parts to a much higher tolerance than a part off the shelf,

    I’m talking about dc conditions.

    However there are some fundamental downsides to monolithic opamps.

    The die materials and construction put constraints on the physical properties that govern current transfer from one part of the die to as another. Heating of the die is a big problem. The tiny internal resisters and transistors do not work as well as single parts. You will not find a class A Opamp on the planet. They are all class B with a smidgen of a milliamp of class A bias.

    They used complex distortion cancelling mechanisms which look good on paper with 0.00004 % THD.
    However, in an audio application they put a lot of class B commutation on the power supply rails.

    They tend not to perform subjectively as well as a simple discrete Opamp.

    If you want a good discrete Opamp go look at Sparko discrete opamps. They have some good reviews.

    Ian

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. JBL MPA 400 Amplifier problems
    By electronicguest in forum Lansing Product Technical Help
    Replies: 0
    Last Post: 11-01-2018, 01:03 PM
  2. Grounding audio circuit for RFI immunity...
    By user in forum General Audio Discussion
    Replies: 1
    Last Post: 11-28-2017, 08:07 AM
  3. Issues about the lm386 audio amplifier
    By millionreason in forum General Audio Discussion
    Replies: 2
    Last Post: 02-02-2017, 05:15 AM
  4. Amplifier Problems - Help!
    By Ducatista47 in forum Professional Amps
    Replies: 12
    Last Post: 06-09-2006, 12:52 PM
  5. More amplifier Problems
    By Ian Mackenzie in forum Professional Amps
    Replies: 15
    Last Post: 05-31-2006, 07:24 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •