Low pass filter - TL072 - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 22nd January 2007, 01:03 PM   #1
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
Question Low pass filter - TL072

I need a low pass filter for my TDA7294 amplifier, found one and it looks very simple

LOW PASS FILTER

please tell me if you have a better schematic (but simple, not too complicated), or if you have a suggestion for the low pass filter above
  Reply With Quote
Old 22nd January 2007, 02:11 PM   #2
Dxvideo is offline Dxvideo  Turkey
diyAudio Member
 
Dxvideo's Avatar
 
Join Date: Nov 2003
Location: Turkey
Send a message via Yahoo to Dxvideo
That works on the same theory but simpler,
Attached Images
File Type: jpg sub xo.jpg (54.4 KB, 950 views)
  Reply With Quote
Old 22nd January 2007, 02:19 PM   #3
sek is offline sek  Germany
diyAudio Member
 
sek's Avatar
 
Join Date: May 2003
Location: Berlin
Depending on what you're aiming for, the website of SL can also never hurt.
  Reply With Quote
Old 22nd January 2007, 03:21 PM   #4
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
tnx

can I use TL072 ???
or if you have a better solution tell me

btw. I need to put this on a single power suply if it is possible? (+12V)
__________________
Nothing to see here...
  Reply With Quote
Old 22nd January 2007, 03:58 PM   #5
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
why do you want a low pass filter?
In my opinion it will remove some of your low bass information.

If you are planning to run with large amounts of equalisation to extend the low frequency response of a speaker, then a low pass will protect the speaker from excessive cone travel and the power amplifier from excessive output voltage.

If you are running the speaker near flat then I suggest you use a DC blocking capacitor on the input to your amplifier and set the RC time constant of this filter (-6db/octave- single pole) to about 80mS to 90 mS. That will let all the bass and sub-bass through and get the best out of the low frequency response in the speaker.

BTW
the circuit in post2 will not work with the late information supplied in post4! nor will the linked circuit in post1.
__________________
regards Andrew T.
  Reply With Quote
Old 22nd January 2007, 04:04 PM   #6
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
Quote:
Depending on what you're aiming for, the website of SL can also never hurt.
it's like this:
I need a 24dB/oct lowpass filter with changeable frequency (up to 200Hz)

and if it's possible a tested one
I don't like when to build something that probably won't work or if it hasn't been tested
__________________
Nothing to see here...
  Reply With Quote
Old 22nd January 2007, 05:22 PM   #7
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Ah!
a low pass to stop the bass getting to your speakers.
I'm afraid your link confused me.

A pair of 2pole Sallen & Key filters cascaded to give 24db/octave.
Do you want Linkwitz Reilly or Butterworth roll off characteristic or something else?

There's a Group Buy and a few spares may be available for a suitable filter (but it's not adjustable).
__________________
regards Andrew T.
  Reply With Quote
Old 22nd January 2007, 05:38 PM   #8
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
Quote:
If you are planning to run with large amounts of equalisation to extend the low frequency response of a speaker, then a low pass will protect the speaker from excessive cone travel and the power amplifier from excessive output voltage.
There is definetly huge amount of equalisation
I have a two-band tone control, bass control range is from -19 to +17dB (I love that little button )
So i need a low pass filter because the range of bass control is from 20Hz to 500Hz, and I don't want anything above 150Hz on my subwoofer.
__________________
Nothing to see here...
  Reply With Quote
Old 22nd January 2007, 05:38 PM   #9
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
Quote:
Ah! a low pass to stop the bass getting to your speakers. I'm afraid your link confused me.


low pass

This is a simple low pass filter with changeable frequency (30-150Hz).
I just want to know what do you think about this schematic (will it work, and would you make any changes to it ?)
__________________
Nothing to see here...
  Reply With Quote
Old 22nd January 2007, 05:50 PM   #10
ch33ta is offline ch33ta  Croatia
diyAudio Member
 
ch33ta's Avatar
 
Join Date: Jun 2006
Location: Croatia
Send a message via MSN to ch33ta Send a message via Yahoo to ch33ta
I must say I am kind of new at all this, so if you know some better filter please give me a link.

btw. tnx for answering on my newbie questions
__________________
Nothing to see here...
  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
GIC low pass filter? capslock Digital Source 19 4th May 2011 04:24 AM
need help with low pass filter prezden Multi-Way 11 12th January 2009 08:04 AM
low pass filter AudioAddicted Car Audio 17 2nd November 2006 06:44 AM
Low pass filter help ifrythings Subwoofers 1 24th February 2006 09:45 AM
Low pass filter Fin Digital Source 2 29th December 2003 02:27 AM


New To Site? Need Help?

All times are GMT. The time now is 12:12 PM.


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