"Anyone willing to spend a little time on writing a one page tutorial..."
Probably better if people want to post questions about applying the clocks to their particular dacs. Please provide schematics and hi-res pics so we can understand the existing topology.
If multiple people have similar questions for similar dacs then a summary of the answers could possibly be compiled.
Otherwise you will probably get one page that says something like, "Use 50-ohm characteristic impedance transmission line from the clock to the dac. Parallel terminate the line either with 50-ohms to ground at the dac end, or else use a squarer with an included terminator at the dac end. Connect the squarer output to the dac clock input. Power the squarer with a clean, appropriately designed 3.3v or 5v power supply depending on the clock input requirements of your dac. Terminate the squarer output with 50-ohms to ground at the dac load end of the 50-ohm transmission line the squarer will drive." Something more or less like that. Is that what you are asking for? If not, then what?
Probably better if people want to post questions about applying the clocks to their particular dacs. Please provide schematics and hi-res pics so we can understand the existing topology.
If multiple people have similar questions for similar dacs then a summary of the answers could possibly be compiled.
Otherwise you will probably get one page that says something like, "Use 50-ohm characteristic impedance transmission line from the clock to the dac. Parallel terminate the line either with 50-ohms to ground at the dac end, or else use a squarer with an included terminator at the dac end. Connect the squarer output to the dac clock input. Power the squarer with a clean, appropriately designed 3.3v or 5v power supply depending on the clock input requirements of your dac. Terminate the squarer output with 50-ohms to ground at the dac load end of the 50-ohm transmission line the squarer will drive." Something more or less like that. Is that what you are asking for? If not, then what?
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Hi Eduard,
I have posted several docs about the implementation of the oscillators and the frequency doublers.
The documents explain how we have implemented the devices which have been measured.
We have used battery power supply, but I have wrote that the DRIXO oscillator is not much sensitive to the power supply, so every low noise regulator is fine.
We have used RG400 coaxial cable with SMA connectors to link every device.
What is not yet clear?
Andrea
I can measure anything you can think of, provided I am waiting long enough for the correlation to do it's magic, and that there's no power outages.
Cross correlation is not different in principle from the common synchronous averaging (in the time domain), used in the regular noise measurement. Long time ago I was able to measure the noise distribution of a LF LNA, down to 1uHz (that's microHertz). After 3 weeks, the 1/f rule was confirmed and physics was saved.
Although many have asked for a scientific approach it looks like no one is really interested.
So I quote myself and ask again someone to define the needed parameters.
I recall reading a paper on the subject of how the brain localizes sound. (sorry can't remember where) After covering the basics of binaural timing the author discussed the notion of detecting and filtering of secondary reflections. He talked about the evolutionary benefit of early humans finding themselves in a dark cave with a lion and the utility of not being confused by reflected sounds when determining location and distance. Struck me as an interesting observation. I think that some in this forum would be running out the cave entrance happy that their brain sorted this out and others would be back in the cave trying to convince the lion that these auditory skills do not exist.
I don't believe, but you can get a Wenzel BT ULN, measure it and the post your results.
And you can use a frequency doubler to measure a 5MHz oscillator like the Wenzel or the Oscilloquartz.
Your questions are either irrelevant to Chris's concerns, or impossible to answer, that's why nobody picks up. They are only yet another of your attempts to score points and polish the image you are trying to promote.
I did measure a MTI oscillator (similar to what you are using as references) and the results were spot on with the data sheet (I can dig for those results, if anybody else would find them relevant, which I doubt, this is not a "mine is larger" contest).
I don't have one of the oscillators you mentioned, and anyways, somehow I don't think you are in the position to tell me what to do.
You can define the method whatever you want, otherwise you demonstrate one more time there is nothing of scientific in your claims.
Please, post the picture of the measurement and the phase noise plot of the MTI.
Ok, a "please" goes a long way (although I doubt you are really interested in the results). I will dig for those MTI phase noise measurement results from about 5 years ago and post them here. It will take some time, this is not very high on my todo list.
And here is the problem. You aren't learning that. But similar to how people think silver wire sounds 'bright' people are converging on common improvements for this clock based on what other people have reported.
Actually very little of that on DIYaudio. Look back 10 years. The thread starter on here is one of the worst bullys, which is why he hit my ignore list.
I would bet money that different people in the same room (one at a time) and the same equipment would perceive a different depth as it's just an illusion conjured from your brain.
I think the basics have been covered and some will be left to experiment to discover on their own.
For example... I have said IMHO
Important:
1. Properly terminated SMA cable torqued to spec
2. Some level of vibration / isolation
3. A decent power supply. A simple linear supply with a LM317 reg will do.
4. A battery supply may be useful to prevent ground loops and isolate the supply
5. Leave power on all the time. 2 months of burn in makes a difference
6. The rest of your system. Reclockpi really helps in a FIFOpi setup. Dedicated low noise reg to Reclockpi also worth the effort. All the stuff you do with the rest will determine to what extent DRIXO makes an impact. You have already that well covered.
Maybe not so important
1. Going nuts with DRIXO PS with 3kF supercaps (perhaps you'll prove me wrong on that one)
2. Worrying about RG400(better) vs cable rated for 1gHz
3. Worrying about ultimate chassis or cable length sub 1m.
For the most part you can just plug it in and it works. All of the stuff listed will affect listening pleasure in very small amount. I saw vibration as important in WTMC v1.0 and SMA cable connection with this one.
If you do something and the sound stage collapses, stop doing it. If you can't fix a ground loop issue try a battery. After that just enjoy it.
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The lack of answer comes due to that everybody (almost) understand that measurements possible to correlate to audible impact need to be in external interfaces - not an internal clock interface. But you just babble on about phase noise from a clock - your problem in a nutshell.
//
Fair enough, I think it's assumptive to conclude what I have or haven't learnt about audio or EE. We have never spoken before, as far as I'm aware. I also don't think there is an issue by developing knowledge through a community. Some of the best things have been developed through open collaboration.
I hope you are right and we see more projects being created here. I am less certain. I think I will just do what I have done for the past year which is remain passive and check in every 2-3 months.
You might be right, but I don't see what the issue is with that. As long as people are enjoying their system and getting what they would like from it. However this is an oxymoron. "I would like to understand the objective measurements" but "everyone perceives something critical to music differently as it's an illusion conjured by your brain."
I will take a leaf out of your book and block the known characters (not you
). Last post from me lads, good luck again Andrea.One last post!
I have experimented with 40mm Panzerholz, Sorbothane, Foam pads, Bitumen (from damping panels), ISO Acoustic Oreo.
I borrowed a friends fluke vibration meter, which he uses for industrial building.
I ended up with my PCB bolted onto Panzerholz, the crystal is set-up as Andrea suggested but instead "glued" to the board with Bitumen. When it happens to be in a modu-shop case, we got slightly better measurements when resting the case on proper weighted sorbothane by placing a kettlebell on top. Unfortunately, it's very hard to get it loaded properly, due to the clocks being so light. So I use Iso Acoustics Oreo's under the modu-shop chassis.
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Absolutely. Agreed. We found common ground!
It is an illusion. And it exists only in the individual brain. It is an inherited trait, but it can be honed and damaged.
I can share an observation. My wife is a stroke survivor. Two key impacts were complete loss of vocabulary, and ability to process sound. No issue with hearing, but the complex circuits that turn the measured sound in the ear into perceived sensory input in the brain was severely damaged. I was honored to spend years helping someone close to me rehabilitate. You are forced to pay attention.
Some standout observations:
-it is shocking how much we filter out sounds choosing what small amount to pass to our conscious mind. In her case normally ignored noise could completely overwhelm and paralyze
-how much effort our brain expends ignoring stuff. And how distressing it can be. Helps explain why bad digital reproduction is so tiring and grating
-and to your point, how easy it is for different people to have different perception of the same sound. In my wife's extreme example relearning the vocabulary was almost complete. Fairly quickly she could hear and understand maybe 22 of the 26 letters. Say A and she'd clearly hear A. Say R, and she would reliably hear static. Now some years later so much is recovered she would be at about the same communications level as President Biden who struggled with similar issues. Generally appears normal, but sometimes stumbles to find a word or use the correct one. But it was fascinating to discover some clues to how different we all are, and how complex auditory perception really is. She cannot stand to be in the same room as a cheap background music. And a great stereo image that I so value completely overwhelms her.
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Agreed, on all counts. Now, can you be specific about what was your motivation behind purchasing Andreas product(s)?
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