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Old 10th May 2009, 04:33 PM   #5491
mige0 is offline mige0  Austria
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Quote:
Originally posted by soongsc

Aren't Earl's files 44.1KHz? It seemed that sample rate based on the text file you posted a while back. If so, what's with the 48KHz sample rate setting here?


I checked with Earl before publishing the processed results - he thought it's rather been 48kHz sampling rate
But anyway - it would only be a mere freqeuncy shift of less than 10% - nothing that interests me in this frame of comparison OB versus horn (OS)

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Old 10th May 2009, 04:38 PM   #5492
soongsc is offline soongsc  Taiwan
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If you look at the timing interval, it clearly is 44.1KHz. Not really sure what it effects because I never tried that.
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Old 10th May 2009, 04:45 PM   #5493
mige0 is offline mige0  Austria
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might be we have got different files - mine is a mere list of numbers (as XPert would have loved it) with no header at all...

Actually, i first did all processing in 44.1k but repeated in 48k after got advice otherwise - again - it does not matter - at least for me


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Old 10th May 2009, 05:11 PM   #5494
ScottG is offline ScottG  United States
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Quote:
Originally posted by mige0



Yes, but I wouldn't go too deep into the very details as we don't have data of other horns to compare with done under same measurement circumstances and – even more important – the ripples are small - not really worth to complain IMO as long as there are no pronounced decay tails that can be seen..

Michael

My recent analysis *only* concerned your results. Basically, it is what it is - look at it for what's shown or don't look at it at all. (..of course you could say the same about any measurement and data "view".)

IMO all that I discussed would in one way or another be audible to a critical listener in a good system. Are the resonances worth complaining about? To some, yes. Would most of it be a big deal? No.

What would likely be most objectionable would almost certainly be the on-axis waveguide + driver resonance (that 1-2 kHz range, particularly as extends to 3+ kHz on axis). Even if it is 30 degrees off of the listening axis, I still think the on-axis portion would be audible.

Again, the net result isn't bad - but it isn't particularly good (and certainly not "stellar").

BTW, Zaph had the DE10 with ME10 waveguide posted here:

http://www.zaphaudio.com/tidbits/

As far as a comparison is concerned, I'd agree that without CSD at different axis's that it is difficult to make a comparison *except* for the on-axis response. However, note the freq. response plots off-axis and how they don't have a great deal of ripple - which likely means that their CSD probably has fewer problems.
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Old 10th May 2009, 07:00 PM   #5495
xpert is offline xpert  Afghanistan
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Quote:
Originally posted by ScottG
IMO all that I discussed would in one way or another be audible to a critical listener in a good system.
With this You emphazise that You have concerns. But we don't know where they come from. If I don't bring those effects to my perception, what is the reason? Bad system, non critical listening?

Quote:
Originally posted by ScottG
What would likely be most objectionable would almost certainly be the on-axis waveguide + driver resonance (that 1-2 kHz range, particularly as extends to 3+ kHz on axis). Even if it is 30 degrees off of the listening axis, I still think the on-axis portion would be audible.
Sorry, there is NO resonance. Take it as said, no resonance. None. What You see is a group delay that comes with bandwith limiting. In this case obviously it is a highpass. Group delay is unavoidable with any common bandwith limiting, may be a horn (mechanics) or crossover (electrics). Calculus and nothing else: No resonance. Not bad. No concerns. No perceptibility. No degradation of zound.

Your misconception is quite common with Cumm. Spectr. Decay. You should leave that CSD reading behind.

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Old 10th May 2009, 07:56 PM   #5496
Rudolf is offline Rudolf  Germany
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Quote:
Originally posted by xpert

Sorry, there is NO resonance. Take it as said, no resonance. None. What You see is a group delay that comes with bandwith limiting.
Interesting aspect. Just to make this comprehensible for my ignorant view - how do I have to understand the above?
- CSDs don´t show resonances at all
- in this specific case the CSD doesn´t show a resonance but a GD
- all resonances must be seen as GD
- ?? else.

I would appreciate if you could make this clearer.

Rudolf
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Old 10th May 2009, 08:21 PM   #5497
mige0 is offline mige0  Austria
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Quote:
Originally posted by Rudolf

Interesting aspect. Just to make this comprehensible for my ignorant view - how do I have to understand the above?
- CSDs don´t show resonances at all
- in this specific case the CSD doesn´t show a resonance but a GD
- all resonances must be seen as GD
- ?? else.

I would appreciate if you could make this clearer.

Rudolf

You'd better not to ask for lots of "explanations" from a troll - you'd better ask for hard work!



Quote:
Originally posted by xpert


Sorry, there is NO resonance. Take it as said, no resonance. None.
....
Calculus and nothing else: No resonance. Not bad. No concerns. No perceptibility. No degradation of zound.


And your proof by own measurement, Mr Xpert?


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Old 10th May 2009, 09:10 PM   #5498
mige0 is offline mige0  Austria
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Quote:
Originally posted by ScottG



My recent analysis *only* concerned your results. Basically, it is what it is - look at it for what's shown or don't look at it at all. (..of course you could say the same about any measurement and data "view".)

IMO all that I discussed would in one way or another be audible to a critical listener in a good system. Are the resonances worth complaining about? To some, yes. Would most of it be a big deal? No.

What would likely be most objectionable would almost certainly be the on-axis waveguide + driver resonance (that 1-2 kHz range, particularly as extends to 3+ kHz on axis). Even if it is 30 degrees off of the listening axis, I still think the on-axis portion would be audible.

Again, the net result isn't bad - but it isn't particularly good (and certainly not "stellar").

BTW, Zaph had the DE10 with ME10 waveguide posted here:

http://www.zaphaudio.com/tidbits/

As far as a comparison is concerned, I'd agree that without CSD at different axis's that it is difficult to make a comparison *except* for the on-axis response. However, note the freq. response plots off-axis and how they don't have a great deal of ripple - which likely means that their CSD probably has fewer problems.

There are good reasons to take CSD with a grain of salt.

First its a highly processed result in order to make obvious what's hidden (well, for the most of us ) and not necessarily telling "the whole truth and nothing else than the truth".
And also not telling about limits where calculation is valid or not.

Second any graph has its limits where we have to decide between "truth" and what we can grasp at most. If you look at the trace below it should become clear what I mean – we are lost in "true" details here:

Click the image to open in full size.

Third, if you imagine the time span of sub 1msec decay - and translate this into how many cycles that my be for the frequencies of interest you easily see that it doesn't make sense to crank resolution (and conclusions) too far – no?




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Old 10th May 2009, 09:41 PM   #5499
ScottG is offline ScottG  United States
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Quote:
Originally posted by xpert


With this You emphazise that You have concerns. But we don't know where they come from. If I don't bring those effects to my perception, what is the reason? Bad system, non critical listening?



Sorry, there is NO resonance. Take it as said, no resonance. None. What You see is a group delay that comes with bandwith limiting. In this case obviously it is a highpass. Group delay is unavoidable with any common bandwith limiting, may be a horn (mechanics) or crossover (electrics). Calculus and nothing else: No resonance. Not bad. No concerns. No perceptibility. No degradation of zound.

Your misconception is quite common with Cumm. Spectr. Decay. You should leave that CSD reading behind.

so long
I'm not entirely sure what you are requesting here. (..and I realize that English as a second language isn't exactly easy.)

I do think I understand what you are referring to with group delay (or at least partially). Presumably you mean that phase rotation from filtration (mechanical or electrical) is inducing time decay problems. Even if I were to accept the laughable argument that neither the compression driver nor the waveguide exhibits any resonant behavior; I have *never* seen simply phase-induced time decay that *looks* like what Michael presented. Also, despite what others may report - I do think that phase-induced time delay can be audible (or "perceptible").

So no, I think you are incorrect on this point. I do think it would be nice though if we had phase and impedance shown as well.. but you work with what you are given.
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Old 10th May 2009, 09:57 PM   #5500
ScottG is offline ScottG  United States
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Quote:
Originally posted by mige0



There are good reasons to take CSD with a grain of salt.


Michael

I don't discount this.. but at the end you have to make a decision (with respect to any measurement):

Do I use it or not?

..and if you do, after a while you will probably start to get a "feel" for the level of accuracy of those results and perhaps even some idea of what those results do subjectively (to the sound).
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