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

The Lounge A place to talk about almost anything but politics and religion.

John Curl's Blowtorch preamplifier part II
John Curl's Blowtorch preamplifier part II
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
Closed Thread
 
Thread Tools Search this Thread
Old 7th June 2012, 09:37 PM   #23791
jneutron is offline jneutron  United States
diyAudio Member
 
jneutron's Avatar
 
Join Date: Jan 2004
Location: away
Quote:
Originally Posted by john curl View Post
In any case, virtually everything that I tried to remove these harmonics from appearing with these specific 'bad' cables has failed, so far, except perhaps by the approach made by Audio Precision which has a number of changes, as well as a number of similarities.
There is a big hint there in the fact that AP doesn't have the problem.

Quote:
Originally Posted by john curl View Post
Now, let's say JN is correct in presuming it is a very low level ground loop that appears to have a 'dead zone' that causes all the harmonic distortion.
THIS is precisely where you have gone off the track.

I have never said that a ground loop appears to have a dead zone..where did you come up with that???

I have stated from day 1, your setup has a ground loop that diverts the harmonics either to the input section, or away from the input section, based on the break frequency of the ground loop.

Read IEEE-STD-1050. That would be a good start for you.

Your equipment is reacting to the integrity of the ground. There are red flags all over your results which show that.

Quote:
Originally Posted by john curl View Post
That might work to remove the distortion products, but what about a NORMAL audio playback system? Would not each and every piece of audio equipment, even made to a professional level, have this problem appear with these specific 'bad' wires or perhaps another set of wires?
You continue to make the flawed assertion that the wire is generating the distortion. It is not. It is a bad setup. The setup is causing the distortion. Edit: And, at the pro level, whitlock is making progress in general, but has yet to address the overall EMC issue..

As to your question regarding a normal audio system? Simple, design the equipment such that it is not sensitive to ground loop currents across the audio bandwidth.

I provided the schematic for that test.

Quote:
Originally Posted by john curl View Post
What if the AP is MISSING SOMETHING that is REAL in the 'real world', and is only seen as an artifact in the 'measurement world'?
What if pigs can fly?? Fix your test setup. You have basic flaws in it.

Quote:
Originally Posted by john curl View Post
Until I have specific evidence that there is something so wrong with my test equipment that it is next to useless, I will continue to use it.
You are welcome to do as you wish, as long as you don't try to re-write physics with unsupported theories..your tests are of value despite your incorrect conclusions.

Quote:
Originally Posted by john curl View Post
Those who criticize me, should get an AP or and ST or an HP339, and get some REAL experience with the measurement process, before speculating what is wrong with my approach.
THAT HAS BEEN DONE, John. You ignored the results.

j

ps..who has been criticizing you? On this thread?

Last edited by jneutron; 7th June 2012 at 09:44 PM.
 
Old 7th June 2012, 10:06 PM   #23792
simon7000 is offline simon7000  United States
diyAudio Member
 
Join Date: Nov 2008
Location: Oakmont PA
John (N)

In my playing around I have found in two cases (A very small percentage!) where there appears to be diode action at very low levels on a mechanical contact.

Now knowing how Galena lead crystals were prized in their day for making AM receivers, it was not a great surprise that such action could occur on some random contact.

So I think there actually may be a real explanation for some UFO sightings!

ES

P.S. I use battery power supplies for all the low level stuff!
 
Old 7th June 2012, 10:34 PM   #23793
Wavebourn is offline Wavebourn  United States
Designer & Technologist
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by bcarso View Post
I used Teflon over bus wire extensively, primarily because there is very little meltback when soldering (and if there is any one had best reduce the soldering temperature and have some good fume hood going, as there's a higher vapor pressure than you want of toxic stuff). One of my supporters in the department joked that I was the only person he knew who made his own wire.
I have to admit, this is the same reason why I prefer teflon insulated wires. However people who design by SIMMing do not know this secret and think that my equipment sounds so nice partially because of some magic properties of wires, while they are simply convinient for prototyping using soldering iron.
__________________
Nothing in the universe is perfect. The ideal things are the ones that are most optimal. Optimization criteria, what matters. When I hear "No Compromise Design", I want to take a sledgehammer and test how impact-proof it is.
 
Old 7th June 2012, 11:08 PM   #23794
jcx is offline jcx  United States
diyAudio Member
 
Join Date: Feb 2003
Location: ..
other people unkowing of stranded silver coated copper teflon wire special problems have their soldered connection fall off at awkward moments
 
Old 7th June 2012, 11:16 PM   #23795
bcarso is offline bcarso  United States
diyAudio Member RIP
 
Join Date: May 2005
Location: Canoga Park, California
Quote:
Originally Posted by jcx View Post
other people unkowing of stranded silver coated copper teflon wire special problems have their soldered connection fall off at awkward moments
Yes, the late Bob Pease had this experience in his early days with Philbrick I recall.
 
Old 7th June 2012, 11:20 PM   #23796
Wavebourn is offline Wavebourn  United States
Designer & Technologist
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by jcx View Post
other people unkowing of stranded silver coated copper teflon wire special problems have their soldered connection fall off at awkward moments
People who knew about this problem before soldering (soaking in resin between wires making their bunch fragile) protected ends of wires by stiff tubing on top of teflon insulation.
__________________
Nothing in the universe is perfect. The ideal things are the ones that are most optimal. Optimization criteria, what matters. When I hear "No Compromise Design", I want to take a sledgehammer and test how impact-proof it is.
 
Old 8th June 2012, 12:05 AM   #23797
vacuphile is offline vacuphile  Netherlands
diyAudio Member
 
vacuphile's Avatar
 
Join Date: Apr 2011
Location: Seaside
Quote:
Originally Posted by Wavebourn View Post
People who knew about this problem before soldering (soaking in resin between wires making their bunch fragile) protected ends of wires by stiff tubing on top of teflon insulation.
Teflon runs like Silly Putty under pressure. So how would that work. Also, molten solder and silver at the right temperature REALLY love each other. It will suck through the capillairies between the wires anyways.

I think the problem might be more with the teflon coax silver on copper on steel wire. Steel can withstand repetitive bending much worse than copper.

vac
__________________
Last in distortion-free reflection.
 
Old 8th June 2012, 12:35 AM   #23798
Wavebourn is offline Wavebourn  United States
Designer & Technologist
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by vacuphile View Post
Teflon runs like Silly Putty under pressure. So how would that work.
It worked well not only in my prototypes, but also in all Soviet military equipment that used teflon wire MGTF.

This one:

Click the image to open in full size.
__________________
Nothing in the universe is perfect. The ideal things are the ones that are most optimal. Optimization criteria, what matters. When I hear "No Compromise Design", I want to take a sledgehammer and test how impact-proof it is.
 
Old 8th June 2012, 01:41 AM   #23799
jneutron is offline jneutron  United States
diyAudio Member
 
jneutron's Avatar
 
Join Date: Jan 2004
Location: away
Quote:
Originally Posted by simon7000 View Post
John (N)

In my playing around I have found in two cases (A very small percentage!) where there appears to be diode action at very low levels on a mechanical contact.

Now knowing how Galena lead crystals were prized in their day for making AM receivers, it was not a great surprise that such action could occur on some random contact.

So I think there actually may be a real explanation for some UFO sightings!

ES

P.S. I use battery power supplies for all the low level stuff!
You are very good.

In the decade of trying to get JC to start this thinking process, you are the first to actually begin to get it. I had hoped he would first, but such is life..

IEEE-STD-1050 details this in a fashion, but requires understanding to arrive at the conclusions.....

Darn, this computer is shutting down in 3 minutes...sigh..

The shield current counters the core current. If the shield current is exactly equal and opposite the core current, there is no problem. And, no field.

The shield resistivity, it's total loop resistance, and any non linearities in the shield to ground connection, determine the quality and quantity of the shield current when a ground loop has been formed.

The problem is, how to make the system impervious to that ground loop current.

ttfn

jn
 
Old 8th June 2012, 03:43 AM   #23800
john curl is offline john curl  United States
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
Poor me, I could never have thought that 'diode' like properties happen in passive components! '-)
__________________
"Condemnation without Examination is Prejudice"
 

Closed Thread


John Curl's Blowtorch preamplifier part IIHide 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


New To Site? Need Help?

All times are GMT. The time now is 02:35 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki