Midrange tone control - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 8th August 2006, 11:41 AM   #1
sam14 is offline sam14  England
diyAudio Member
 
Join Date: Jul 2004
Location: Leicester
Default Midrange tone control

Hi, I would like to build a design based around the Pultec MEQ5 EQ but am not very electronically minded. I want to add some mid-cut at 1,2,3,4 Khz. Could someone tell me what the combo L & C values need to be at these freqs? Is it straightforward to calculate them? I have seen the MEQ5 schematic but couldn't figure it out! Doh! Thanks in advance
  Reply With Quote
Old 8th August 2006, 12:19 PM   #2
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Click the image to open in full size.

Hi,

you need to use or scale to the ~ 500R series resistor, the 270R
Q control and the inductor and capacitor values set by SW2.

This assumes your input can handle 600R loads.

/sreten.
  Reply With Quote
Old 8th August 2006, 10:44 PM   #3
sam14 is offline sam14  England
diyAudio Member
 
Join Date: Jul 2004
Location: Leicester
Thanks, Sreten. If I've worked it out correctly then, 1Khz is 108mH & 220nF; 2Khz is 34mH & 170nF; 3Khz is 34mH & 68nF and 4Khz is 34mH & 38nF? Also, is the transformer I/P essential or can I use 600R / 510R at the I/P of some unbalanced phono connectors? Thanks again.
  Reply With Quote
Old 9th August 2006, 11:33 AM   #4
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Download tina ti free circuit sim and check that it works.

(stick an op-amp in the corner unconnected to get it to work, then
use AC analysis to plot the frequency reponse, quick and easy)

600R is a fairly hefty load for an output - can the equipment
drive 600 ohm loads ?

/sreten.
  Reply With Quote
Old 9th August 2006, 01:42 PM   #5
sam14 is offline sam14  England
diyAudio Member
 
Join Date: Jul 2004
Location: Leicester
tina ti?
  Reply With Quote
Old 11th August 2006, 03:44 PM   #6
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
http://focus.ti.com/docs/toolsw/fold...t/tina-ti.html
  Reply With Quote
Old 11th August 2006, 08:42 PM   #7
sam14 is offline sam14  England
diyAudio Member
 
Join Date: Jul 2004
Location: Leicester
Thanks again, will give it a try
  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 for my GC aditaquil Chip Amps 5 6th January 2005 11:39 PM
TI's Tone control JhonDoe Chip Amps 26 13th July 2004 01:29 AM


New To Site? Need Help?

All times are GMT. The time now is 10:13 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