Spice simulation - Page 10 - diyAudio
Go Back   Home > Forums > Design & Build > Software Tools

Software Tools SPICE, PCB CAD, speaker design and measurement software, calculators

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 17th May 2007, 12:18 AM   #91
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
Quote:
Originally posted by peufeu


Actually it isn't "mine" ; the idea to apply this to audio comes from Gérard Perrot of Lavardin.


Noted. Nonetheless, it's a very nifty concept.
I backed into a related idea with the Aleph-X. I suggested the idea of attaching the front end MOSFETs in that circuit to a block of metal--note: Not a heatsink, just a simple block of metal--to stabilize the temperature of the front end by addition of mass. The devices were operated well within their rated power dissipation, but the DC offset was sensitive to thermal drift. The block of metal was intended to act as a "thermal capacitor" that would minimize the drift.
A partial model is not particularly useful because it tends to lead to false confidence. Assuming that a complete model can be written, that would be a useful step forward.

Grey
  Reply With Quote
Old 17th May 2007, 12:49 AM   #92
PB2 is offline PB2  United States
diyAudio Member
 
PB2's Avatar
 
Join Date: Sep 2004
Location: North East
Blog Entries: 1
Quote:
Originally posted by Bob Cordell



Hi Pete,

These are all great points.

Were you an IC designer? I was also.

Bob

Hi Bob,

The short answer would be yes, but I don't really feel like one, more of a systems/design engineer. My emphasis in school was analog design, RF and microwave design, then got pushed into digital on the job, which lead to computer architecture and custom processors.

I did a lot of board level design, then started chip design in the 90s, mostly VHDL and to gates through synthesis. If people don't believe in simulation what will they think of synthesis?

How about you?

Pete B.
  Reply With Quote
Old 17th May 2007, 12:57 AM   #93
PB2 is offline PB2  United States
diyAudio Member
 
PB2's Avatar
 
Join Date: Sep 2004
Location: North East
Blog Entries: 1
Quote:
Originally posted by GRollins
There are too many quirky, weird things in audio.

Grey
Yes, I know, I certainly do know! LOL!
  Reply With Quote
Old 17th May 2007, 12:58 AM   #94
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Quote:
Originally posted by PB2
If people don't believe in simulation what will they think of synthesis?
I think just about everybody believes in simulation, but they also
need to recognize that the map is not the territory.

  Reply With Quote
Old 17th May 2007, 01:05 AM   #95
PB2 is offline PB2  United States
diyAudio Member
 
PB2's Avatar
 
Join Date: Sep 2004
Location: North East
Blog Entries: 1
Quote:
Originally posted by Nelson Pass


I think just about everybody believes in simulation, but they also
need to recognize that the map is not the territory.


Sorry, I should have said some people, but certainly some here offered a blanket dismissal of SPICE. And to be honest I don't want to get into it any further just offered my view.

Pete B.
  Reply With Quote
Old 17th May 2007, 01:24 AM   #96
andy_c is offline andy_c  United States
Banned
 
Join Date: Apr 2003
Sorry for being off-topic here, but I wanted to thank Glen, Pete, Rodolfo, Bonsai and peufeu for their encouragement and suggestions on the microcontroller front.

Regarding the topic, I'd like to mention one thing I like about SPICE.

It has no agenda. It may give wrong answers according to the GIGO principle, but it won't give a wrong answer due to purely political reasons .
  Reply With Quote
Old 17th May 2007, 02:22 AM   #97
diyAudio Member
 
Join Date: Mar 2007
I didn't really read this whole thread, but coming from a newbie who knows nothing about electronics, other then what I have read in the past 4 months, I can say this at least...


Simulation or not, chris makes the most sense. He put it accurately when he stated that u use tools of inaccuracy all the time.


Coming from a HIFI diy audience, the only real tool u own is the ear. With that said, tube guys will stand off in another corner telling u distortion of the right kind is better then none at all. Or at least thats how I understand the proverbial argument(don't kill the newb for his POV).

Anyway, there is a difference between those that design for pure listening enjoyment and there is those that design for worse case scenario's under any circumstance that comes to mind. Simulations will work for a good portion of those instances. But as stated, it has its limitations. Those that are not understood by the programmer and engineers designing todays technologies.

Now get back to work!


BTW, I can think of plenty of real world engineering disasters. Those of which that couldn't have been tested in the real world prior to building. At the same time plenty of simulated models have been built in the real world and work flawlessly.

It does prove the final point, nothing can compare to the final end product result. Try it before you buy it!!!!
  Reply With Quote
Old 17th May 2007, 02:43 AM   #98
diyAudio Member
 
Join Date: Feb 2001
Location: Columbia, SC
You know what I'd like to see?
I'd like to see some of the guys who do liquid-cooled CCD imaging devices for astronomy show up here. Or SETI. Or perhaps high-sensitivity naval sonar. Something along those lines. I imagine that they run into some of the same it-ain't-in-the-book stuff that we have to deal with. Their insights might be useful, indeed.
I've been in and around computers for over thirty years now and have not learned one single thing of use for audio. Nada. I've got a buddy who knows a fair amount amount about the ignition systems in cars. How much is applicable to audio? Zip, as far as I can tell. There's a place in town that builds motors. Cross pollination with audio? None. But maybe, just maybe, fellas who have to take an analog signal and amplify the ever-living (mumble) out of it--without adding noise, mind you--now, they might be able to tell us something interesting.
Yes, I water cool my amps. No, I'm not willing to go cryogenic on my phono stage just to lower the noise...
...wait a minute...
Just kidding. It'd be a pain in the butt.
Still, I'd like to pick their brains over a beer. Better yet, single malt Scotch or a good wine.

Grey

P.S.: Now I've gone and seriously annoyed myself. A cryogenic phono stage. Oh, bother. Now, I've got to go look up some equations as to temperature vs. noise. Just how cold would it have to be in order to do any good? (Cuz it's for sure it ain't in a simulator...)
Be the first on your block to have a truly quiet phono stage!
Hell, be the first in your nation.
Perhaps hemisphere.
Oh, double bother!
  Reply With Quote
Old 17th May 2007, 03:14 AM   #99
Tim__x is offline Tim__x  Canada
diyAudio Member
 
Join Date: Jun 2004
Location: Edmonton area, Alberta
[Devil's Advocate] Actually... LTspice let's you do noise analyses, and it does include temperature effects (static only). A .noise line and a .step TEMP line are all you need [/Devil's Advocate]

P.S. I have no idea if it's actually accurate, I use spice, but don't bother with .noise commands.
  Reply With Quote
Old 17th May 2007, 07:35 AM   #100
diyAudio Member
 
ashok's Avatar
 
Join Date: Jun 2002
Location: 3RS
Most phono preamps have 'hiss' levels significantly lower than the surface noise of the vinyl disc that is playing. At loud levels the hiss though slightly audible is immediately masked when the stylus hits the groove.
So do we really need a 'noiseless' phono preamp considering the difficulty in lowering the noise levels significantly using current components ? Ideally yes but practically........ ?
__________________
AM
  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
Need help with Spice simulation overmind Everything Else 4 23rd December 2002 04:58 PM


New To Site? Need Help?

All times are GMT. The time now is 01:20 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