TIM generator - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

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
Thread Tools Search this Thread
Old 3rd May 2007, 11:08 PM   #1
diyAudio Member
darkfenriz's Avatar
Join Date: Jun 2004
Location: Warsaw
Default TIM generator

Hi all

I would like to know your opinions.
I want to build a simple circuit for presentation what actually TIM in classic Otala meaning is and how it really sounds like and preferably I'd do it on line level.
My choice will probably be ua741 working at high output, like 15Vp-p swing followed with a voltage divider.
What do you think? Any ideas how to sex it up so that it generates TIM anyone can hear?

best regards

P.S. How about 4558?
  Reply With Quote
Old 3rd May 2007, 11:28 PM   #2
lineup is offline lineup  Sweden
diyAudio Member
lineup's Avatar
Join Date: Dec 2005
Location: the north
transcendental interstage modulation ??
or what is it?

I am interested to hear also some TIM.
Don't know if anyone have heard it ....

I wonder how to create this ... hmmm
Another question is:
how high the level - before we can begin to notice TIM

As harmonic dist is probably possible to hear/notice at levels like 1-2%
and is said humans is more sensitive to TIM,
this means we could do with
a TIM-generator circuit capable to deliver at least 1% TIM distortion

I think PMA - Pavel Macura should know about this.
He has suggested some new Intermodulated signal for Audio Amplifier Testing

  Reply With Quote
Old 3rd May 2007, 11:42 PM   #3
diyAudio Member
darkfenriz's Avatar
Join Date: Jun 2004
Location: Warsaw
Transient InterModulation Distortion
  Reply With Quote
Old 4th May 2007, 05:18 PM   #4
diyAudio Member
darkfenriz's Avatar
Join Date: Jun 2004
Location: Warsaw
  Reply With Quote
Old 4th May 2007, 08:31 PM   #5
diyAudio Member
EchoWars's Avatar
Join Date: Dec 2002
Location: Left of the Dial
Maybe TIM is a figment of someone's imagination after all...?
  Reply With Quote
Old 5th May 2007, 12:27 AM   #6
diyAudio Member
Join Date: Mar 2007
Location: Canandaigua, NY USA
No idea how to do this, and as I understand TIM, if you limit the input signal bandwidth to the audio range, you'll never see it. I'm always amazed when people do square wave tests without considering the rise and fall times of the wave. A good square wave generator will put you way out into the RF with ease. Would one connect an RF generator to their amp? I have a very nice circuit that does nothing but set a specific slew rate- anything below that is untouched, anything above is slew limited, but that's not the same thing. On a similar note, I'd like to build an amplifier with adjustable IM distortion to see what it sounds like and how much is detectable. No idea how to do that either. It would also be useful to have an amplifier with adjustable THD, but with the distribution also adjustable, since the higher harmonics are supposed to be so audible. My guess is that all these things are best done with a DSP unless somebody here has some ideas in the analog domain.
  Reply With Quote
Old 5th May 2007, 12:41 AM   #7
diyAudio Member
john curl's Avatar
Join Date: Jul 2003
Location: berkeley ca
Large amounts of TIM soften the sound. This has been done to great extent and accuracy at a Finnish hospital. I would have first thought that it would sound harsh, BUT actually what happens is that IM byproducts are produced that grow like grass and eventually take over the original signal. You can easily see this on a spectrum analyzer measuring TIM with a sine-square test signal.
"Condemnation without Examination is Prejudice"
  Reply With Quote
Old 5th May 2007, 03:10 AM   #8
diyAudio Moderator Emeritus
lumanauw's Avatar
Join Date: Oct 2002
Location: Bandung
Send a message via Yahoo to lumanauw
The sound? PRR said like splattering treble everywhere.
3,000pFd could turn everything to mush, treble splattering all over the audio band.
Attached Images
File Type: gif 301-tim.gif (8.6 KB, 235 views)
  Reply With Quote
Old 5th May 2007, 08:47 PM   #9
OzMike is offline OzMike  Australia
diyAudio Member
Join Date: Apr 2007
I think TIM = transcendal Imaginary Mirage

If it takes such overcompensation to generate, it seems unlikely in anything with a reasonable slewing rate, one that's faster than the signal.

  Reply With Quote
Old 6th May 2007, 12:16 AM   #10
diyAudio Member
darkfenriz's Avatar
Join Date: Jun 2004
Location: Warsaw
Thanks David, that's exactly what I wanted.
TIM in classic Otala meaning
I meant that Daugherty, Otala, Curl and others observed and measured something that without doubt was a distortion not enough stessed before, I don't want to discus their reasoning and results and how real is it in modern designs.
  Reply With Quote


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
what is a Pulse Generator used for ?? redrabbit Equipment & Tools 1 13th June 2007 07:06 PM
looking for a signal generator Ahmad_tbp Solid State 21 8th September 2006 11:37 PM
DIY signal generator? Loial Parts 13 19th September 2005 10:36 AM
distorsion and generator tuben Equipment & Tools 0 2nd August 2004 06:53 AM

New To Site? Need Help?

All times are GMT. The time now is 04:11 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2