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 12th September 2012, 04:43 PM   #27591
Waly is offline Waly  United Kingdom
diyAudio Member
 
Waly's Avatar
 
Join Date: Jan 2011
Location: London
Quote:
Originally Posted by Joshua_G View Post
1. I didn't say I don't hear differences in blind test – I do hear differences, at least in some of them.
2. I didn't say that if I don't hear differences, the test must be faulty.

What I said is that in order for such a test to be valid, first it have to show that it can produce also positive results.
Hi Joshua:

Assume we would both agree to DBT the following statement:

"Joshua can hear differences between A and B", where A and B are, for example, two power cords.

What would be an example of "positive results", as you mentioned above?
  Reply With Quote
Old 12th September 2012, 04:49 PM   #27592
diyAudio Member
 
Join Date: Apr 2005
Location: Sitting behind the 'puter screen, in Illinois, USA, planet earth
What is not obvious is that our “hearing” is an adapted skill which because it is learned, also includes what you already know and even less obviously includes what you see. In hearing acuity tests, the object is to evaluate your hearing alone and so there are NO visual clues and an effort made to exclude any external sounds.

A fun demonstration of that “invisible to us” link between what we see and “hear” is the McGurke effect.
Try this and ponder why we only hear sonic reality when we don’t see anything related to the source AND how a blind test (conducted w/o visual stimulus like a hearing acuity test) can give a very different impression of “hearing” than a sighted one.

Try The McGurk Effect! - Horizon: Is Seeing Believing? - BBC Two - YouTube

Best,
Tom Danley
Danley Sound Labs
__________________
Bring back mst3k and futurama
  Reply With Quote
Old 12th September 2012, 04:54 PM   #27593
Pano is offline Pano  United States
diyAudio Moderator
 
Pano's Avatar
 
Join Date: Oct 2004
Location: Milliways
Blog Entries: 4
Quote:
Originally Posted by SY View Post
At the speaker terminals; same with level adjustment. Just about any amp is flat into a resistor, but if the source impedance is high, it won't be into a speaker load.
Cool, that makes sense. I think many people take FR to be into a pure resistive load, which may not be fair.
Quote:
For the case of a line amp (which is what I thought we were talking about), at the power amp input- but I haven't seen a non-flat one in decades, it's trivially easy to do.
Right. I'd still be interested to blind test circuits with different harmonic content or output impedance.
  Reply With Quote
Old 12th September 2012, 04:57 PM   #27594
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Quote:
Originally Posted by Pano View Post
Right. I'd still be interested to blind test circuits with different harmonic content or output impedance.
Well, you have some experience with DBTs. The issue with output impedance is avoiding the unintended effects on level and frequency response (I know you know that, I'm jes' sayin' for completeness).
__________________
"The way to deal with superstition is not to be polite to it, but to tackle it with all arms, and so rout it, cripple it, and make it forever infamous and ridiculous."- H. L. Mencken
  Reply With Quote
Old 12th September 2012, 05:01 PM   #27595
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by Waly View Post
Hi Joshua:

Assume we would both agree to DBT the following statement:

"Joshua can hear differences between A and B", where A and B are, for example, two power cords.

What would be an example of "positive results", as you mentioned above?
Yes, it will (for that particular test). Not all DBT are the same.
  Reply With Quote
Old 12th September 2012, 05:36 PM   #27596
coluke is offline coluke  Italy
diyAudio Member
 
Join Date: Mar 2009
Quote:
Originally Posted by SY View Post
Well, you have to explain why that doesn't happen for frequency response, level, data compression, phase, and other phenomena that are routinely detected in a DBT. Also, why that doesn't happen for other sensory DBTs (e.g., organoleptic, haptic).
No explanation at all - was only speculating on my experience when switching between CD and SACD versions of the same program; it sometimes happened that after discovering in the SACD some details I had never heard before, I noticed I was able to hear the very same details when reverting back to the CD version. Bias power...?

L.
  Reply With Quote
Old 12th September 2012, 05:51 PM   #27597
Waly is offline Waly  United Kingdom
diyAudio Member
 
Waly's Avatar
 
Join Date: Jan 2011
Location: London
Quote:
Originally Posted by Joshua_G View Post
Yes, it will (for that particular test). Not all DBT are the same.
Huh? It will what? I asked for an example of "positive result" in this particular DBT.
  Reply With Quote
Old 12th September 2012, 06:03 PM   #27598
Jakob2 is offline Jakob2  Germany
diyAudio Member
 
Join Date: Jun 2004
Location: germany
@ zinsula,

thanks for the reminder.


@ SY,

Quote:
Originally Posted by SY View Post
Since we beat the Fremer deal to death months ago, why do you want to beat it around more?
Seems that requesting some data to back up your assertions beats something to death, mhm?

Quote:
Is it total ignorance of statistics?
Could you please present an argument containing some statistics (or data) to shed a light on this?
Which obvious statistical result was ignored by me?

Quote:
Or an insistence on accepting post hoc reframing when it suits your desires?
What was the "post hoc reframing" in the Fremer case??

Quote:
Or a desire to accept poorly controlled results when that suits your desires?
Do you have any evidence that the results were "poorly controlled" in the Fremer DBT at the AES-Convention?

Quote:
People can either hear these things with ears-only or they can't.
It is my experience that people indeed can hear such things if the tests don´t include additional confounders they are not used to.
And yes (that is pretty basic stuff in psychology/sensory testing as well) a controlled listening experiment is a confounder by itself.

I´ve cited ITU-R BS.1116 and the other recommendations for subjective evaluation quite often; please reread the parts which describe the efforts to let the (even the expert panel) listeners accustom to the materials and test protocols.

Quote:
No-one claiming "magic" differences has offered up any reliable evidence. Period. Trying to kick up unrelated dust to confuse the issue doesn't change it, nor does constant moving of the goal posts.
If bringing scientific requirements back to memory is "to kick up unrelated dust to confuse ...." i am guilty.
  Reply With Quote
Old 12th September 2012, 06:25 PM   #27599
Jakob2 is offline Jakob2  Germany
diyAudio Member
 
Join Date: Jun 2004
Location: germany
Quote:
Originally Posted by SY View Post
<snip>Problem is, there's no reliable DBT data showing that, for boxes of gain, anything other than frequency response (assuming no clipping) and level are audible....
No problem at all; zinsulas proposal is reasonable- a positive control is an effect that must be detected under test conditions and of course it should be comparable up to a certain degree.

If the experimenter doesn´t really know what to search for that presents a difficulty, but it is no excuse for violating the scientific rules.

An experimenter has to show that the experiment is objective, valid and reliable.

Quote:
Nope, all it takes is good data.
Of course.

Quote:
Well, you have to explain why that doesn't happen for frequency response, level, data compression, phase, and other phenomena that are routinely detected in a DBT. Also, why that doesn't happen for other sensory DBTs (e.g., organoleptic, haptic).
Who says it does not happen??
In fact it does happen all the time in controlled listening experiments; please reread the documentation of public tests with quite big sample sizes, for example the stereophile test on amplifiers.
  Reply With Quote
Old 12th September 2012, 06:30 PM   #27600
diyAudio Member
 
Joshua_G's Avatar
 
Join Date: Nov 2008
Location: Small village, Israel
Quote:
Originally Posted by Waly View Post
Huh? It will what? I asked for an example of "positive result" in this particular DBT.
When in a certain blind test I hear differences between say power cables, that certain test is capable of giving positive results. Else, I don't understand your question.
  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 08:21 AM.


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