John Curl's Blowtorch preamplifier part II - Page 651 - diyAudio
Go Back   Home > Forums > Member Areas > The Lounge

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

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 4th November 2010, 06:58 AM   #6501
wrinkle is offline wrinkle  United Kingdom
diyAudio Member
 
Join Date: May 2010
Please expand, I know they are quite loud, but what else puts you off?

Wrinkle
  Reply With Quote
Old 4th November 2010, 07:01 AM   #6502
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
They create distortion, their regulation is redundant when one already has voltage regulators following the circuit, and they are physically noisy. For some industrial applications they are just fine. I had a 1400W unit myself, once.
  Reply With Quote
Old 4th November 2010, 11:13 PM   #6503
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Heard an interesting presentation by David Greisinger just now at the AES.
Subject is how can we determine not just direction but also position/range of a sound source in the presence of many similar sources. Example: two string instruments that produce same pitches and harmonics at two different angular positions but still we can hear them separately.

Not sure I understand any and all points but it appears to involve the phase shift between the harmonics of a particular source. In other words, even if two sources have the same harmonic structure we still can discriminate between them and focus on each separately, using the phase relationship between the harmonics. If the phase relationship between the harmonics remains intact we can determine position/range even with other similar interfering sources.

When you have a reverberant venue, at a certain point in time the phase relations start to smear and you can't locate the source anymore. That is one reason why location gets difficult with reverberation sound arriving very close after the direct sound, but not if there is enough time between direct and reverb sound for the brain to do its location processing.

Might that have some relation to why some amps that measure identical to other amps, nevertheless have better soundstage and localization? Because they better preserve the phase relation between the harmonics in the distortion products?

Thoughts?

jan didden
__________________
I won't make the tactical error to try to dislodge with rational arguments a conviction that is beyond reason - Daniel Dennett
Check out Linear Audio Vol 7!
  Reply With Quote
Old 4th November 2010, 11:24 PM   #6504
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
You want a copy of "The Psychology of Music" 2nd edition,
edited by Diana Deutsch. There is some excellent material
regarding grouping mechanisms (aka binding), particularly
ch. 9.

  Reply With Quote
Old 5th November 2010, 04:14 AM   #6505
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally Posted by Nelson Pass View Post
You want a copy of "The Psychology of Music" 2nd edition,
edited by Diana Deutsch. There is some excellent material
regarding grouping mechanisms (aka binding), particularly
ch. 9.

$ 104 paper back !!?? I think I'll get that for xmas. The used one

jan didden
__________________
I won't make the tactical error to try to dislodge with rational arguments a conviction that is beyond reason - Daniel Dennett
Check out Linear Audio Vol 7!
  Reply With Quote
Old 5th November 2010, 02:18 PM   #6506
diyAudio Member
 
Join Date: Nov 2008
Location: Oakmont PA
Quote:
Originally Posted by janneman View Post
$ 104 paper back !!?? I think I'll get that for xmas. The used one

jan didden
It is a textbook. So the price is high because most purchasers are required to buy it. However as the major book in the field almost every major university library has a copy.

If buying online do not confuse it with the 1938 book of the same title but different author.
  Reply With Quote
Old 5th November 2010, 02:33 PM   #6507
diyAudio Member
 
abraxalito's Avatar
 
Join Date: Sep 2007
Location: Hangzhou - Marco Polo's 'most beautiful city'. 700yrs is a long time though...
Blog Entries: 98
Send a message via MSN to abraxalito Send a message via Yahoo to abraxalito Send a message via Skype™ to abraxalito
Quote:
Originally Posted by janneman View Post
$ 104 paper back !!??
A bit cheaper is Bregman if this stuff captivates you (it does me). I've recently acquired this but not delved into it yet.

Amazon.com: Auditory Scene Analysis: The Perceptual Organization of Sound (9780262521956): Albert S. Bregman: Books
__________________
It doesn't have to take the form of a conspiracy, rather a consensus... James H Kunstler
  Reply With Quote
Old 5th November 2010, 04:52 PM   #6508
diyAudio Member
 
Join Date: Jun 2007
Quote:
Originally Posted by abraxalito View Post
A bit cheaper is Bregman if this stuff captivates you (it does me). I've recently acquired this but not delved into it yet.

Amazon.com: Auditory Scene Analysis: The Perceptual Organization of Sound (9780262521956): Albert S. Bregman: Books
I would also endorse the Al Bregman book in favor of the other.

Although parts of it are bit dated now, he was an important and capable contributer to the field. As far as the David Greisinger work goes, at this point I would not get too excited about it.
  Reply With Quote
Old 5th November 2010, 10:22 PM   #6509
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
My colleague, Ron Quan has his give his paper:'New Techniques for Evaluating Audio Amplifiers via Measuring for Induced Wow and Flutter and Differential Phase Distortions'.
Works for me.
  Reply With Quote
Old 7th November 2010, 12:00 AM   #6510
diyAudio Member
 
scott wurcer's Avatar
 
Join Date: Jan 2004
Location: cambridge ma
Quote:
Originally Posted by john curl View Post
My colleague, Ron Quan has his give his paper:'New Techniques for Evaluating Audio Amplifiers via Measuring for Induced Wow and Flutter and Differential Phase Distortions'.
Works for me.

Wow and flutter are mechanical terms and make no sense in the context of purely electrical measurements.
__________________
Silence is so accurate.
  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



New To Site? Need Help?

All times are GMT. The time now is 09:59 PM.


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