Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Different approach using litz wire for tonearm wiring
Different approach using litz wire for tonearm wiring
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 7th June 2019, 11:24 AM   #31
Mark Tillotson is offline Mark Tillotson
diyAudio Member
 
Join Date: May 2018
Location: Cambridge UK
I understand perfectly - this is what a simplifying assumption is all about, making things easy and simple, which you seem hell-bent to avoid. If I was sending a signal over kilometres of twisted pair I would have to worry about this, and also about the attenuation (which is part and parcel of the breakdown of the lossless approximation at low frequencies and long lines)

If you are sending signals a few metres only, you can assume all terminated transmission lines have constant Z0 from DC to the cutoff frequency, and are lossless at low frequency, and this is assumed widely and relied on in many many disciplines. Losses increase at higher frequencies due to skin effect and imperfect dielectrics, but with minimal disruption to Z0.

You are coming at this from the direction of telecomms perspective, which is different from all the short signal distribution applications.

The breakdown of the lossless assumption happens when the power losses become significant, and at this point the line is no longer a transmission line in the normally accepted sense anyway, as it is dominated by resistance, not wave propagation. For typical audio cables this would happen at lengths of 100's of metres, which is never seen.
  Reply With Quote
Old 7th June 2019, 11:47 AM   #32
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Originally Posted by Mark Tillotson
If you are sending signals a few metres only, you can assume all terminated transmission lines have constant Z0 from DC to the cutoff frequency, and are lossless at low frequency, and this is assumed widely and relied on in many many disciplines.
I can't speak for what many discipline may or may not assume. However, you continue to mix up two quite different phenomena: the irrelevance of a short line, and the correct termination of a significant line. I am not trying to avoid simplicity, but I am trying to avoid oversimplification. There are lots of engineers who actually believe that the characteristic impedance of a cable is sqrt(L/C) at all frequencies; using a simplified approximation where it is not valid is something they sometimes do. You seem to be encouraging this sort of confusion, however clear things may be to you.

So can we agree:
1. the characteristic impedance of some twisted wire is not 100 ohms at audio frequency
2. this does not matter if the wire is short
  Reply With Quote

Reply


Different approach using litz wire for tonearm wiringHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
litz wire senthilkumar Car Audio 4 16th August 2018 02:13 PM
Litz Wire for audio applications (18AWG, New England Wire Type 2) Chook81 Vendor's Bazaar 2 24th January 2012 08:32 PM
litz inductor wire for speaker wire. fazman Everything Else 126 20th June 2011 02:48 PM
LITZ wire gearheaddruid Swap Meet 0 11th January 2005 05:07 AM
Litz Wire - Where to buy? ClassD Parts 0 5th April 2004 06:37 AM


New To Site? Need Help?

All times are GMT. The time now is 03:31 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki