TI's Tone control - 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 3rd July 2004, 03:53 AM   #1
JhonDoe is offline JhonDoe  Philippines
diyAudio Member
 
Join Date: Jan 2004
Location: ac
Angry TI's Tone control

hi!

I would like to build the conplete tone control from aplication bulletin of TI (http://focus.ti.com/lit/an/sboa082/sboa082.pdf) for my computer and need some help for getting the values of the pot(the Bass and Treable). What will be the best values for this pot's?

I will connect this tone control in my GC(inverted vertion) the application show's for non-inverted do I need R11(1meg) and R12(22k)?

my plan is to remove the balance pot and the two limitting res. just a volume pot. do u tink 50k will be sufficient for this?

one more thing. the schematics shows in page 1 figure 1 the 2 resistors R6 are 11k whch have the same value but in page 2 figure3 R6 have a different value 11k and 22k. which is correct for the figure?



  Reply With Quote
Old 3rd July 2004, 06:43 AM   #2
JhonDoe is offline JhonDoe  Philippines
diyAudio Member
 
Join Date: Jan 2004
Location: ac
anyone pls help me in my ignorance in mathematical figures!!????
  Reply With Quote
Old 3rd July 2004, 03:53 PM   #3
diyAudio Moderator
 
JojoD818's Avatar
 
Join Date: Mar 2003
Location: searching...
Hi,

I have built that one and based on the app note, I used a 100K linear pot. It sound is worth building, but be smart in choosing your opamps. Read their corresponding datasheets for further references.

HTH,
JojoD
  Reply With Quote
Old 3rd July 2004, 03:55 PM   #4
diyAudio Moderator
 
JojoD818's Avatar
 
Join Date: Mar 2003
Location: searching...
I forgot, I used both 11K.
  Reply With Quote
Old 3rd July 2004, 07:12 PM   #5
diyAudio Member
 
metal's Avatar
 
Join Date: Jan 2004
Hi

You can use OPA134/2134. or OPA227/2227, OPA228/2228.
As they are intended for audio use.

Kind Day
  Reply With Quote
Old 4th July 2004, 03:09 AM   #6
BC is offline BC  United States
diyAudio Member
 
Join Date: Jan 2004
Location: Milwaukee,Wisconsin-USA
I contacted TI a few months ago about that app. information. If you study the schematic there are errors. If you read the information, there are errors. TI told me that the author no longer works for BB/TI. Your Math isn't necessarily bad. Sorry for negative information.
__________________
Everything is relative to something. A key to communication is agreeing on a reference point.
  Reply With Quote
Old 4th July 2004, 09:31 PM   #7
diyAudio Member
 
metal's Avatar
 
Join Date: Jan 2004
You can download OPA227 Datasheet, you will find another tone control circuit
  Reply With Quote
Old 4th July 2004, 10:09 PM   #8
Svante is offline Svante  Sweden
diyAudio Member
 
Svante's Avatar
 
Join Date: Feb 2004
Location: Stockholm
Interesting to note in that schematic is that if you turn the volume up to max, and the balance max sideways, one input gets shorted. For other volumes, the L-R balance will shift with the volume pot position, unless it is centered.
__________________
Simulate loudspeakers: Basta!
Simulate the baffle step: The Edge
  Reply With Quote
Old 5th July 2004, 01:12 AM   #9
JhonDoe is offline JhonDoe  Philippines
diyAudio Member
 
Join Date: Jan 2004
Location: ac
thanks guys!...

Quote:
Originally posted by JojoD818
Hi,

I have built that one and based on the app note, I used a 100K linear pot. It sound is worth building, but be smart in choosing your opamps. Read their corresponding datasheets for further references.

HTH,
JojoD
did u mean 100k for both(treble and bass)?


Quote:
Originally posted by BC
I contacted TI a few months ago about that app. information. If you study the schematic there are errors. If you read the information, there are errors. TI told me that the author no longer works for BB/TI. Your Math isn't necessarily bad. Sorry for negative information.
I thought it was me who have not undestand the figures in that app.


I got another question guys.. in power amp stage I'm running the chip in inverted topology, the app. shows the power amp in non inverted, can i remove the two input res before and after the input cap???
  Reply With Quote
Old 5th July 2004, 09:41 AM   #10
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
hi,

you may want to try dual 250k linear taper for the bass, and 50k for the treble, also linear taper....

you can not remove the resistor after the input cap to the opa549 amp. it is meant to bias the input on the op amp...the 1meg is high enough and is better to leave it as is....
__________________
the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
  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
Tone control pre-amp digi01 Chip Amps 16 13th June 2011 07:18 AM
i need preamp schematics w/o tone control or volume control hernanstafe Parts 7 30th January 2008 03:12 AM
Tone Control One Knob Need Help prorms Solid State 15 3rd September 2007 03:46 PM
Tone Control for my GC aditaquil Chip Amps 5 6th January 2005 11:39 PM


New To Site? Need Help?

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