John Curl's Blowtorch preamplifier part II - Page 2752 - 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 10th September 2012, 08:29 PM   #27511
diyAudio Member
 
john curl's Avatar
 
Join Date: Jul 2003
Location: berkeley ca
JohnL, you are on track.
  Reply With Quote
Old 10th September 2012, 09:08 PM   #27512
diyAudio Member
 
Join Date: Aug 2012
If you go back to the coin toss analogy a blind test is the same thing as tossing an unfair coin and a double blind test is the closest thing anybody knows to tossing a fair one.

In the former case the test is insensitive to sample size because it has an inbuilt error.

If you look at the y axis of a Gaussian distribution as the true figure then tossing an unfair coin also converges to a Gaussian distribution but the mean is offset to one side.
A fair coin one the other hand has its results randomly distributed around the true mean and thus its accuracy is increased by the number of tosses, i.e. the number of samples you have.

In the end why science works is because it is consensual and not individual.
It is necessary for at least two people to agree that there is a world outside of them that has certain characteristics that are so despite what differences in their subjective of it experience might be. As soon as you do this you have statistics because it is the only way we know of separating the objective from the subjective, and if there was no difference then none of the electronic devices we use would work anyway.
rcw
  Reply With Quote
Old 10th September 2012, 11:03 PM   #27513
coluke is online now coluke  Italy
diyAudio Member
 
Join Date: Mar 2009
Quote:
Originally Posted by Johnloudb View Post
All a double blind test will tell you is that the subjects couldn't identify a difference in a blind test.
Which is exactly what a DBT is supposed to aim to, and the reason why it is a well established - and useful - procedure in drug testing. On the other hand, all an open test will tell you is that subjects are actually able to identify a difference when they know a difference exists - not really useful.

L.
  Reply With Quote
Old 10th September 2012, 11:44 PM   #27514
fas42 is offline fas42  Australia
diyAudio Member
 
fas42's Avatar
 
Join Date: Jun 2012
Location: NSW, Australia
Blog Entries: 11
Quote:
Originally Posted by Johnloudb View Post
The brain turns up the gain on sounds with special meaning or importance, while others are habituated (habituation of perception) to these sounds of no significance.
Part of the dilemma is that some people have heard really good audio sound, that's totally convincing, and the others haven't. And the latter therefore believe the former lot are deluding themselves, for various reasons. So the divide remains, those that know what's possible are quite content, in one sense, to be disregarded, they have the quiet satisfaction of knowing the "higher truth"; and the other lot keeps haranguing these miscreants, in their desire to ensure, enable a uniformity of thinking and beliefs.

Me ..., like yesterday, just wind up the system on some reasonably well recorded blues to what some would call deafening, but which are just realistic sound levels, what it would sound like, standing near the muso's, and just smile ...

Frank

Last edited by fas42; 10th September 2012 at 11:47 PM.
  Reply With Quote
Old 11th September 2012, 12:10 AM   #27515
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Quote:
Originally Posted by fas42 View Post
Part of the dilemma is that some people have heard really good audio sound, that's totally convincing, and the others haven't.
Exactly, and after I heard possible quality of reproduction I hear how "different" all setups "from the box in the store" are.
After somebody hears how close to real performance can be sound reproduction that person will never forget it and the difference between "The Real High End" and "Nice sounding set-up" will be obvious. It is like "ear-opening" experience.
Unfortunately I never heard such set-ups that don't beg for some improvements, so the journey is going on. Closer and closer to complete fooling the imagination as if it sounds "here and now", but still not there.
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 11th September 2012, 12:46 AM   #27516
fas42 is offline fas42  Australia
diyAudio Member
 
fas42's Avatar
 
Join Date: Jun 2012
Location: NSW, Australia
Blog Entries: 11
Quote:
Originally Posted by Wavebourn View Post
Unfortunately I never heard such set-ups that don't beg for some improvements, so the journey is going on. Closer and closer to complete fooling the imagination as if it sounds "here and now", but still not there.
Yes, that's the next "headache" .... The better it gets, the more the subtle deficiencies can be heard, the more you can hear into the mix, and the slightest edginess stands out like a sore thumb. But, my happy "discovery", , is that ultimately they can all be knocked over, all these lower and lower level problem areas, until you can't actually imagine it being able to be better ...

It really is like tuning a F1 machine, the slightest maladjustment will throw the performance off kilter relatively severely, it can be tiresomely frustrating a lot of the time ...

Frank
  Reply With Quote
Old 11th September 2012, 01:01 AM   #27517
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
I have some different experience: the better you get one parameter, the worse is other. Find solution to minimize first 2 problem all together, but get a new one as the result. And so on.
__________________
The Devil is not so terrible as his math model is!
  Reply With Quote
Old 11th September 2012, 01:39 AM   #27518
fas42 is offline fas42  Australia
diyAudio Member
 
fas42's Avatar
 
Join Date: Jun 2012
Location: NSW, Australia
Blog Entries: 11
Well, I 've certainly had the experience of trying something which does improve one aspect but another worsens, or appears to do so. This is the subjective quality of the sound that I'm talking about, of course. And there are a number of aspects to this ...

One is that frequently the sound is more detailed after changes but apparently also harsher. This I always take as a good sign, this is the proverbial "lifting of the veils", I'm going in the right direction. A smooth but non-informative sound is definitely taking the wrong turn; everything that tells me more and more about what has been captured on the recording is good. This of course means that difficult tracks are a nightmare to listen to for the time, but worry not: this is cutting with coarse strokes to get to the heart of the matter. The last step, so to speak, is to resolve the more subtle issues which are the underlying causes of the unpleasantness of the sound -- this is the sandpapering to continue the analogy -- and then it all falls into place - you get the big sound which is effortless to listen to ...

And another aspect is that when one parameter of sound quality is improved it just allows you to hear "deeper" into the sound: things that were always "wrong", before, are now unmasked, so another round of effort is needed to knock over, smooth out, the next level of less obvious "bumpy" bits ..

Frank
  Reply With Quote
Old 11th September 2012, 02:32 AM   #27519
diyAudio Member
 
Join Date: Aug 2012
The whole point is that all of these types of considerations are controlled for by the fact that if the participants dont know what they are listening to, or for, then priori assumptions of these sorts are not relevant because you have to have information to hang them on.

This is why the single blind test that seems beloved of some in diy audio is invalid because one lot of participants know what is being tested and in what order.

If you then only indicate that a switch has taken place, even if it is switched to the same device again and ask someone whether they liked the sound before or after such a nominal switch event, then if there is truly no audible difference the statistical results will be randomly distributed, and in the case of a truly double blind test the skewing effect is only due to the sample size.

All of the subjective baggage that people might bring is as far as possible eliminated, and it is very unlikely that a randomly selected sample will be skewed in any way by such considerations anyway.

This type of test is also applicable to a single individual as well as a randomly selected group, but manufactures are generally not interested in single people but in demographic groups.
rcw
  Reply With Quote
Old 11th September 2012, 02:35 AM   #27520
diyAudio Member
 
Johnloudb's Avatar
 
Join Date: Feb 2008
Quote:
Originally Posted by fas42 View Post
Me ..., like yesterday, just wind up the system on some reasonably well recorded blues to what some would call deafening, but which are just realistic sound levels, what it would sound like, standing near the muso's, and just smile ...

Frank
Frank, you should really be more careful about protecting your ears. Live levels can damage hearing of course, but also cause hyperacusis. Audiophiles have a tendancy to gradually turn up the volume over time to get that same level of excitement. This is also an example of habituation. Our tolerances increase but our auditory system can only handle so much. It's not just the sound level but the length of time you listen at that level that causes damage. Better to use restraint than pay later, IMHO.
__________________
My Website: Hyperacusis, Tinnitus, My Story
  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 04:09 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