John Curl's Blowtorch preamplifier part II - Page 510 - 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 23rd July 2010, 11:06 AM   #5091
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally Posted by Rod Coleman View Post
Jan, how do you know he designed them , if you don't even know the type numbers?
He makes a living designing amps for big and niche manufacturers. You didn't think all he does is writing about blameless amps do you?
One series he recently designed are the XD (cross-over displacement series) for Cambridge.

jd
__________________
If you don't change your beliefs, your life will be like this forever. Is that good news? - W. S. Maugham
Check out Linear Audio!

Last edited by jan.didden; 23rd July 2010 at 11:09 AM.
  Reply With Quote
Old 23rd July 2010, 11:08 AM   #5092
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally Posted by jacco vermeulen View Post
I have personal knowledge that it's hard to impress Swiss gals with a fancy watch and an uggy face, there.
Maybe you should have left out the face?

jd
__________________
If you don't change your beliefs, your life will be like this forever. Is that good news? - W. S. Maugham
Check out Linear Audio!
  Reply With Quote
Old 23rd July 2010, 11:15 AM   #5093
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally Posted by zinsula View Post
[snip]I don't know if Ipods can play uncompressed material, but I seem to recall(don't ask for refercences...) that there was an article that compressed music at high enough bitrate cannot be distinguished from uncompressed 16/44.1 in DBT's. Should do for most Non Rolex people.
As always and everywhere in life there is a continuous scale between uncompressed and, say, 32 kbps compressed. At some point on that scale you get to the point where statistically, people cannot expect to hear the difference. Where is that point? Depends. I know from direct observation that Stuart is pretty good at hearing the difference between 256 kbps and 384 kbps. Some people might be happy with 128 kbps as 'the same as uncompressed'.

But if you think that anybody should be able to hear the difference between uncompressed and whatever compression is used, on any material, all the time, you are incorrect.

jd
__________________
If you don't change your beliefs, your life will be like this forever. Is that good news? - W. S. Maugham
Check out Linear Audio!
  Reply With Quote
Old 23rd July 2010, 11:15 AM   #5094
работник
diyAudio Member
 
Rod Coleman's Avatar
 
Join Date: Jul 2004
Location: Warwickshire UK
Yes, you'd have to read the whole thread to see the actual references to Doug's words.

As you say, I think we broadly agree, but my emphasis is much heavier against Audio Designers who do not give an account of listening assessment. I know that he makes useful remarks about certain design considerations, BUT, architecting an amp around what you can measure ONLY, is not good enough.

'convince a critical audience'? well, pointing to a thread here on DIYaudio, where more than just the thread starter and his best friend have listened, and reported positively - to give an example
  Reply With Quote
Old 23rd July 2010, 12:26 PM   #5095
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by SY View Post
No, they're not.
So you say, though the facts are different.
It is quite obvious you are avoiding direct answers to my questions as they were asked.

Quote:
Originally Posted by SY View Post
The idea that I have "trade secrets" is totally hilarious, since I publish my schematics, detailed design information, show my calculations, and my exact thoughts on design tradeoffs. Even more hilarious because I don't do audio professionally. Never even sold a circuit board. The most I've done is made some pizza money from my articles. My profession is polymer science. Ask me how to formulate a polypropylene without antioxidants that cause endocrine disruption and THEN it's likely I'll clam up.
The idea is probably hilarious. So there must be a different reason for you holding your cards close to your chest when it comes to the relationship between measurements and sound quality. Time after time you avoid giving detailed replied, other than "search". It definitely looks like you have something, or you think that you have something, which you consistently refuse to share on the forums here.

Quote:
Originally Posted by SY View Post
It might help to actually read the stuff I've published. I'm not designing for you, but there's a slim possibility that you could learn something.
I've read carefully your articles about your line stage and phono stage. For some considerations of yours which you mentioned in those articles and for some other considerations which you didn't mention, I opted to build amps according to other designs.

Quote:
Originally Posted by SY View Post
Really? You must be confusing me with someone else.
Really. All I read from you is invalidation of any listening test mentioned, while I didn't see you mention even once that listening evaluations are valid, or what listening tests may be valid and how you think they should be performed. This is yet another indication for you holding your cards close to your chest when it comes to the relationship between measurements and sound quality.
  Reply With Quote
Old 23rd July 2010, 12:39 PM   #5096
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
Quote:
Originally Posted by janneman View Post
amps for big and niche manufacturers.
+ Audiolab

Mr Self has some parallels with Nelson Pass, imo.
He does consultancy work, writes articles, and does his own thing with the Signal Transfer Co.
Mr Pass published measured THD specs of the 2nd generation Silmic, Mr Self did that in the late 1980s for other Elna caps.

(it's hard to get around in Zug, wearing a paper bag)
  Reply With Quote
Old 23rd July 2010, 01:04 PM   #5097
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Quote:
Originally Posted by Joshua_G View Post
Really. All I read from you is invalidation of any listening test mentioned, while I didn't see you mention even once that listening evaluations are valid, or what listening tests may be valid and how you think they should be performed. This is yet another indication for you holding your cards close to your chest when it comes to the relationship between measurements and sound quality.
Gee, wasn't it you for whom I wrote a detailed protocol for a listening test (I think it was wires), at your explicit request, taking quite a bit of my time, just to have you then say that you weren't really interested in doing a controlled test?

If you haven't read my numerous posts about listening tests, methods, and controls, not to mention the custom-designed protocol you got from me, please read and understand them before totally making up things again. I realize that I'm not a great writer, but my stuff is reasonably understandable even to a non-native English speaker.
__________________
The more you pay for it, the less inclined you are to doubt it.- George Smiley
  Reply With Quote
Old 23rd July 2010, 01:11 PM   #5098
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
Apparently, Joshua has no preference for sucking on people's brain or patience.
  Reply With Quote
Old 23rd July 2010, 01:17 PM   #5099
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by SY View Post
You could certainly make an excellent (i.e., sonically transparent in a blind bypass test) unity gain stage using bipolars, FETs, opamps, or tubes. Rolex or Patek-Philippe? It's still 4:20.
1. I don't know what you mean by "blind bypass test" and how it should be peformed.
2. If this is so, why did you choose a tube (and transformer) for the gain stage of your "Heretical preamp"?
  Reply With Quote
Old 23rd July 2010, 01:33 PM   #5100
PMA is offline PMA  Europe
diyAudio Member
 
PMA's Avatar
 
Join Date: Apr 2002
Location: Prague
SY, tell us. Hopefully Dr. Lipshitz et al do not read here
__________________
Pavel Macura
http://web.telecom.cz/macura/audiopage.html
  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 09:35 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