So what is it exactly (the number) you consider as audible threshold? If it is "x", can you hear "x+1"? If it is "x+1", can you hear "x+2"? The point is, thresholds are different from person to person. But what could be a surprising thing is if human's brain is actually much better than what the human think...
This is my hypothesis. That human is actually "affected" by subtle things... Something that they cannot do with their conscious mind but they can with their sub-conscious mind... (of course this is just another "hypothesis" you can laugh at)
Of course this is true (has an effect and could be the dominant effect or even worse the only effect) but it should not invalidate possibilities... At some point every one (including those at Benchmark) are just guessing...
Hmmm... then there is big possibility that you are right, that the jitter shouldn't be the one responsible with audible differences, if it does exist. But I do believe there exist differences, except that I don't think jitter is the reason... They mention "analog", which is more like it...
If you look at the Dunn paper I linked to yesterday it gives audible thresholds based on science. Ed said 12nS system Jitter. The 12 year old benchmark DAC1 is 150pS.
My view is that anything >100dB down is inaudible. Jitter spuria from the DAC1 are all >120dB down. Jitter is not an issue. Knowing you have the lowest jitter DAC on the block may tip your appreciation of the music tho.
Just to repeat: Benchmark DAC2 is superbly engineered and measures as well as anything for not much money compared to say DCS with their $100k w*nkfest stack. But also $300 gets you something that reason says is transparent. Tis a golden age for affordable and superb equipment.
And the standard list of measurements for the DAC2 is even more impressive. I do not have a solid answer for why it sounds more accurate nor for that matter why masters and CD do not sound the same. Jitter and the already very good analog was improved on according to the designer. But there is some data outside the standard measurements and tests not usually done. In looking for answers, some extraneous things fall out and other practical issues in implementation and interfacing. System-wide grounding and shielding is not always as good as it is on an isolated equipment T&M.
Now we are nearing the end for CD (mechanical drive mfr are down to one). More and more products are portable and wireless...... DAC outputs go to an rf/antenna for local signal distribution. What does wireless do to the signal? IM/THD, noise, dynamic range. Which RF system is the cleanest today. Tomorrow? We just finish getting things pretty good and then its another new game to optimise.
[pride of ownership isnt the issue for me.... peace of mind is]
THx-RNMarsh
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You also don't have any evidence that any of those assertions are true. But if you repeat them enough times, Tinker Bell will live!
Yah, but that's because you mounted a 130dB klaxon over the control room seats that wails when the system unlocks.😉
John
Ah it would have to be louder than that, the crowd noise is!
Gee the guys who do live music also use an external clock and they would think a 130 db klaxon was a bit muffled and as long as it matched the beat they would reinforce it!
So if it is 12 nS in a football stadium, what would it scale to in a bit quieter place?
(Actually it was a service call. They noticed something was wrong. Turned out in the off season someone noticed the pilot light and unplugged the master clock.)
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I though you said the control room guys noticed it. Are you telling me the control room is that loud?? I would not want to work in that, OSHA would certainly have an issue as well.
When the receivers no longer see the master clock, what happens? Do they fail, stutter, mute, or make it up as they go along??
The whole story is sounding fishy to me. You're not from Pennsylvania now, are you? I mean, granted, it is april 1 and all..
John
Cool a single page out of context. But looking at their claim they are saying that, if you are below -5dBSPL due to jitter it's inaudible. Ignoring the impossible SPL for now that says that >-125dB down is inaudible. Which the $300 muscial fidelity DAC hits with flying colours. The DAC1 is only -121dB in the midrange so yes clearly it will sound awful...
They mix with the window open so they can hear what is going on. Each device will run it's own clock and synchronize with the data if no clock is present. The peak levels in any stadium certainly do exceed OSHA levels. The crowd normally makes way more noise than the sound system. But just as you would expect a warning klaxon..
The noise level can drop to the mid 40 dBs and guys from the control room walk the bowl at the start to be sure all the loudspeakers are working. Yes they notice little things like increased distortion, blown tweeters and even dead loudspeakers. You would be surprised how many folks do not notice items like that. (Even with one loudspeaker out the surrounding ones will provide sound, but of a lesser quality.)
So why are you so contrary since your sex change? (4-1 🙂 )
Based on zero data, just an unsourced handwave (and not a very clever one), a phone call, and some ad literature.
Ignoring the actual data which is out there in the literature, cited here over and over.
data/work was from Dunn and Hawksford.
well, that is one interpretation, i guess. there are others.
I have seen numbers from 2ps to 250ns. And, is it random or correlated give very different results. So choose what you like to defend your position.
I have no reason yet to doubt the main differences in digital are as stated- jitter and analog artifacts/distortion.
-RM
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Benchmark DAC2 vs. DAC1 - Side-by-Side Measurements - Benchmark Media Systems, Inc.
Refreshing. They say
Refreshing. They say
they also note that the poor low level balance between channels on the DAC1 may be audible. But no mention of jitter...
Actual listening test data. Crazy, I know.
Yes, I pointed that out. Richard may not understand the things he's citing. Notice that "jitter" has now transmuted to "jitter and analog artifacts/distortion" and "CD players" has transmuted to "main differences in digital (DAC)."
There's a pony in there somewhere!
Just linking it again http://www.nanophon.com/audio/jitter92.pdf this is from the original 1992 Dunn paper and the 20ps number is only for 20kHz, and even then other research quoted on that paper suggests 250ps is inaudible for a 20k signal.
No SY.... reread... i said the designer thought the differences heard were due to jitter and to analog improvments.
Actual listening.... correlated noise or random? Correlated is more than 10 times more sensitive. yes, I have read the aes et al, too.
I think your arguing with me is the wrong person. You might ask the designer to prove what ever he did in those areas are audible.
IMO what he did is audible. Could be unbal vol control improvement at low level? No. That isnt the result I hear.
WE also talked about the digital audio signal on HDMI cables and a product to correct the timing errors there. Lots of things that arent published.
THx-RNMarsh
Actual listening.... correlated noise or random? Correlated is more than 10 times more sensitive. yes, I have read the aes et al, too.
I think your arguing with me is the wrong person. You might ask the designer to prove what ever he did in those areas are audible.
IMO what he did is audible. Could be unbal vol control improvement at low level? No. That isnt the result I hear.
WE also talked about the digital audio signal on HDMI cables and a product to correct the timing errors there. Lots of things that arent published.
THx-RNMarsh
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Benchmark need to tidy their links up, but finally found there 'is it audible' paper. Benchmark DAC2 vs. DAC1 - Is There an Audible Difference? - Benchmark Media Systems, Inc.. Conclusion is that if you listen to mp3s the DAC2 is better....
Lets see, 340 meters per second....1 meter per 3 milliseconds. nearfield speakers 10 meters away (30 mS), across the field maybe 70 meters (210mS), ends perhaps 100 meters away (300 mSec)
So, they open the windows of the control room (assuming it's on the 50 yd line), and with a time of flight ranging from say 30 milliseconds to 300 milliseconds with multiple source delays and reflections (even the distributed row reflections which are really interesting), and lo and behold, they can clearly hear jitter caused by a master clock failure whereby locally generated clocks take over, resulting in a 12 nSec jitter. Thereby, 12 nSec jitter is noticeable in a football stadium??
Whoa.
John
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