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Old 23rd January 2013, 04:36 PM   #641
labjr is offline labjr  United States
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Quote:
Originally Posted by BrianDonegan View Post
Speakers (generally) cannot, however
Isn't there a difference between timing and frequency response?
 
Old 23rd January 2013, 04:38 PM   #642
labjr is offline labjr  United States
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Quote:
Originally Posted by pinnocchio View Post
Maybe you're right and I'm not debating but too many people see or hear things that are in their heads... Trust me there's many examples.

I bet you take that the same song have it well converted over from 24/768 to 24/192 make them hear then take the same song again without them knowing and tell them that it is the 768 version and all of a sudden there's more magic or the other way around and now it is not as good but the same 768 file twice!

Just saying
Do
Seems like a silly argument.

I tend to respect Robert Watts' research and opinions. Chord has a reputation for making good products. So he must be doing something right.
 
Old 23rd January 2013, 05:00 PM   #643
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...always enjoy reading your comments, Barrows...

Your point is well taken regarding options for shaping inputs to the DAC because all of our systems operate with different inherent flaws. As I've tweaked the digital side of my system, I have found that SQ of most 44.1 material improved more - sometimes much more - than material that is natively 88.2 and up. Initially this was counter-intuitive. The digital tweaks did not 'lift all boats (program material) equally' - they also produced better performance by compensating for analog-side limitations affecting mostly redbook material. So to the extent that filtering can make a DAC play nice with amps and speakers, great! But for basic fidelity in real world (non ultra high end) systems, I think the greatest benefits are on the low end rather than the high end of the sampling frequency spectrum. ...and yes, I'm working on my analog side now, before I consider how to retire the aging I2S interface...

Good luck to Russ in getting the USB interface tweaked to the Buffalo without too much pain and suffering! I think the demand will be there...

Cheers,

Frank
 
Old 23rd January 2013, 05:09 PM   #644
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Quote:
Originally Posted by labjr View Post
Isn't there a difference between timing and frequency response?
There is not. Transient speed is limited by the high frequency response of the loudspeaker. For example, to reproduce a theoretical instantaneous transient (vertical leading edge of waveform) would require a loudspeaker of infinite bandwidth.
In the real world, my listening has suggested that 24/176.4 (or perhaps 32 bit, just to allow for more manipulation in mixing, etc) is an adequate sample rate to achieve the best real world performance possible. This would also suggest that 2x DSD is adequate as well. And the limiting factor for real world performance is the performance of the digital filters. At 24/176.4 and above, digital filtering, when done right, is essentially inaudible.
There are some electronics with much wider bandwidth now (Spectral), but until we have speakers capable of a huge increase in bandwidth, I see no reason for sample rates above 24/176.4-24/192. In fact, designers would probably be better off spending their efforts on other areas of audio to make improvements. Additionally, increasing audio system bandwidth comes with a lot of other problems, such as resolving unwanted RF signals... Some designers (yes, this is somewhat controversial, and there are those who argue the opposite POV) are even in favor of purposefully limiting bandwidth as a path to better audio performance. Looking at the response curves of even the best tweeters, those designers may have a point!
 
Old 23rd January 2013, 06:01 PM   #645
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Russ & Brian: can handle DSD?
 
Old 24th January 2013, 10:52 PM   #646
labjr is offline labjr  United States
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I emailed Robert Watts of Chord and he replied promptly. Here is part of what he wrote.

Its not the rise time of transients that is important but the timing of
them. An adult cannot hear above 16kHz but can detect very fine
differences in timing between one ear and another.
 
Old 25th January 2013, 01:03 AM   #647
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It's not just about what ears and the brain can do, but what transducers and other such things can do.
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Old 25th January 2013, 04:50 AM   #648
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Fuel to the fire or food for thought:

24/192 Music Downloads are Very Silly Indeed
24bit vs 16bit, the myth exploded!
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"People can't do what they should: room acoustics and speaker design - so they do what they can: new amps, cables etc." (Lidia)
 
Old 25th January 2013, 05:00 AM   #649
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Default Hahaha...

Quote:
Originally Posted by labjr View Post
I emailed Robert Watts of Chord and he replied promptly. Here is part of what he wrote.

Its not the rise time of transients that is important but the timing of
them. An adult cannot hear above 16kHz but can detect very fine
differences in timing between one ear and another.
better put your head in a vise then, and have very precise measurements made of the ear to tweeter difference for where you set up that vice, all that precision will be lost with even the most minute difference in distance from one a pair of speakers... or listen to a single speaker in mono for everything...

BTW, I fail to see how the timing of a transient could be unrelated to rise time????
 
Old 25th January 2013, 06:03 AM   #650
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Why to chill on this frequency point: The primary neurons in the Organ of Corti within the ear are wired as probable filters, even before sending transduced info on to the brain. There is nothing 'flat' about the system. The incredible acuity of good ears was developed through evolutionary history as an asset in mere survival, of course. (Is that a very big kitty creeping up on me? ) In such a diverse population as ours, we must expect that significant natural variation among individuals is the rule, not the exception. What one person swears by, another 'normal' person possibly cannot hear. And it is all good... [Thus it was with some skepticism that I first dabbled in the black art of transducer mods but in the end the cone tweaks sounded very much like adding Tridents to the Buffalo! ...just my ears, maybe not yours...]

2 channels via USB is a great place to start. The aspect of the new XMOS products that seems cool is their purpose-specific scalability (though I have read little detail). I vote for a chip with the guts to at least run multi-way crossover filters with timing adjustments! ...or a little room correction... How sweet would those be? And what better DAC to pair with that than the new 8 channel Buffalo? Not that those DSP jobs can't be done before the USB bus, but it IS inconvenient to keep those crossover filter channels clean and clear - especially compared to not needing a host computer at all! USB = , and if XMOS inputs other than USB might eventually become available then this new interface (+DSP?) should be relevant for a good while. Again, good luck!

Frank

Last edited by francolargo; 25th January 2013 at 06:25 AM.
 

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