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Old 17th November 2012, 04:51 PM   #29411
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Wasn't it dizzy after going 'round and 'round on the spool?
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Old 17th November 2012, 05:01 PM   #29412
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Scott, if you are brave, just ask Dick Sequerra. He can tell you, as he told me this morning.
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Old 17th November 2012, 05:15 PM   #29413
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Quote:
Originally Posted by john curl View Post
Scott, if you are brave, just ask Dick Sequerra. He can tell you, as he told me this morning.
Did he use verbal only language?
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Old 17th November 2012, 05:25 PM   #29414
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Originally Posted by scott wurcer View Post
How does the wire know its direction, what if it decides to switch, and what about AC it goes in both directions?
And what about effects of full moon effects on gravity Vs electron masses ?
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Old 17th November 2012, 05:26 PM   #29415
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Dick Sequerra referred me to early books on crystal alignment, found by X-ray studies. Got any ideas?
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Old 17th November 2012, 05:28 PM   #29416
RNMarsh is offline RNMarsh  United States
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Default Bridging the test gap -

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Originally Posted by gpapag View Post
Ref. Distortion measurement, perception and masking:
Alex. Voishvillo (now with JBL)
ALMA 2009 Europe
http://www.almainternational.org/***...0acoustics.pdf

George
This paper is excellent in bridging the gap between objective testing and listing/hearing loudspeakers and in particular- masking and deserves some comment here - maybe we need to use only tests for IM difference products which are "invisible to THD". - Need multi-tone stimulous.

- Masking is much less at low SPL listening levels. Higher unwanted harmonics are not masked.
- Weighting very appropriate for unmasked harmonics.
- masking isnt total... more like attenuation in many cases.... or we couldnt hear much going on in complex music, such as classical.
- The work is most useful with high distortion - like dynamic drivers. The conclusion I have a hard time with... to use the knowledge to sort of hide and cover up the poor driver performance. I guess if you have taken the dynamic driver technology as far as you can and its still pretty bad, you can use this approach.

Thx- RNMarsh

Last edited by RNMarsh; 17th November 2012 at 05:42 PM. Reason: for clarity
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Old 17th November 2012, 05:28 PM   #29417
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I haven't tried the full moon, but 'time of day' seems to matter.
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Old 17th November 2012, 05:36 PM   #29418
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Alex is OK!
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Old 17th November 2012, 05:43 PM   #29419
RNMarsh is offline RNMarsh  United States
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Default OK? As in --

I'm OK, Your OK.
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Old 17th November 2012, 05:58 PM   #29420
jcx is offline jcx  United States
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This paper is excellent in bridging the gap between objective testing and listing/hearing and in particular- masking and deserves some comment here - maybe we need to use only tests for IM difference products which are "invisible to THD".
Quote:
Originally Posted by gpapag View Post
...
Ref. Distortion measurement, perception and masking:
Alex. Voishvillo (now with JBL)
ALMA 2009 Europe
http://www.almainternational.org/***...0acoustics.pdf
...
George


the paper's results are usefully applicable to such grossly nonlinear systems as loudspeakers

test any of the mentioned metrics, thresholds, distortion levels against a audio power amp designed intelligently with at least the background knowledge of Doug Self, Bob Cordell's audio amplifier books and you will get Ron Quan's repeated table captions from his latest paper:

Table xx lists "X" amps that were at the residual level for
"Y test"

Quote:
- Need multi-tone stimulous.
duh - read Cabot's AP distortion analyzer manual chapters, papers - defines SOTA in "conventional audio measurents" - includes multiple mutlitome formats from SMTE to FastTest

http://www.tmesystems.net/tmecommz/a...Audio_Meas.pdf

we can build audio amps that measure perceptually transparent by all of the meausres outlined in the Voishvillo paper - and make the measurements with a modern AP analyzer

Last edited by jcx; 17th November 2012 at 06:13 PM.
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