I don't think we have. Done a fair bit of work on this.
But really, why don't you come to your own conclusion, after all that is why this thread has been established. We can all sit on the sidelines and make comments, that's fine, but in this instance there is a better way.
Try it for yourself.
Cheers, Joe
That's correct. Unless you have done ears-only testing, the plural or anecdote does not become data.
So, will you be presenting any actually valid data to show audibility, and if audible, any differences from the same filtering applied elsewhere in the signal chain?
I said this too all the time, and I promoted this idea always in connection to this approach.
Even more, I think this is the key to find out more in this, to find a way to get facts out of this, measurements method, and so on.
One may try it and then conclude something, another one may have different or the same conclusions (based on his own knowledge and appreciations). Somebody else may find something more, doing his own experiments in this area.
All these things or individual conclusions /observations discussed here it may lead to more solid conclusions, it may bring more facts, etc.
Only comment from "outside" it is not enough. I may invite all those who experienced this filtering method to come into discussion, with their own observations and conclusions based on very real experiment, and/or on their individual knowledge.
Only so I can see a progress into this field... Else we risk to transform this discussion in a never ending commenting about the posts from one or another.
Please explain. By what do you mean "done ears-only testing"?
What is the format you require?
BTW, this isn't rocket science, this is DIY where you can test it for yourself. So now it's my turn to ask the question, will you?
Or else, this discussion belongs on the Blowtorch II where nothing ever gets done - or extremely rarely.
Cheerfully Yours, Joe
I'm not the one claiming something here. Burden of proof and all that.
In any case, please read my Linear Audio article (available for free on Jan's website) for an outline of a few of the different ways that ears-only testing can be done, how and why controls are put into place, and a few examples. When you have understood the basics, if you want help in setting up a valid test, drop me an email and I'll be happy to help you.
The other alternative is measurements demonstrating differences greater than reasonable audible thresholds.
Even better is both, but either will do if you want to determine if the hypothesis is valid. Of course, all of this depends on a desire to find out what's actually correct. Not everyone wants to do that, which is why there's often so much emotional resistance to doing controlled testing ("What if I can't actually hear what I thought I could hear????").
In any case, please read my Linear Audio article (available for free on Jan's website) for an outline of a few of the different ways that ears-only testing can be done, how and why controls are put into place, and a few examples. When you have understood the basics, if you want help in setting up a valid test, drop me an email and I'll be happy to help you.
The other alternative is measurements demonstrating differences greater than reasonable audible thresholds.
Even better is both, but either will do if you want to determine if the hypothesis is valid. Of course, all of this depends on a desire to find out what's actually correct. Not everyone wants to do that, which is why there's often so much emotional resistance to doing controlled testing ("What if I can't actually hear what I thought I could hear????").
You make it sound like a sin or something?
OK, let's say I plead guilty, then what are you going to do then?
I have given you the obvious solution and I am quite sure that you are very capable of putting this to the test yourself.
Would it surprise you that I, more than even you, would love that. And sometimes patience is a virtue, so in time we shall have that too I believe - and guess who will be most pleased.
More like an observation rather than a hypothesis - and yes, I am quite familiar with the rules of falsification etc.
But this is not rocket science, this is DIY. So I think I have done the right thing by putting all on the table, open for discussion and testing. I don't have unlimited resources and I suspect what would satisfy you may be very difficult. I am not using that as an excuse - again I reiterate, I would love to be able to furnish what you ask for - in fact I believe we are much closer than you think.
OK, I will get the article, but it strikes me that you want proof based on your terms - your article. Is that unfair to point out?
As strange as this sound, you say help and that is always the environment I have sought. It is one that I have thrived upon in the past. But I am not so used to the straight jacket environment that I have encountered here - I am more used to one where we were encouraged to say anything that came into our heads, even the craziest things, because we knew that at least some of those madcap ideas could proved fruitful, or stir another more logical connection in someone else in the room. Those were the days I remember fondly. Alas, some of them are no longer with us.
Cheers, Joe
-
Use other papers or texts, if you like; I suggested mine because it's relatively brief and accessible, not that it breaks new ground or has special demands. This is just basic controls we're talking about. Ears only. No peeking. No preconceptions. You hear it or you don't.
This is what separates an honest desire to find out what's actually true from playing make-believe.
That has already been suggested in earlier threads. Joe rejects it in favour ofwintermute said:
This is astonishingly unlikely, as it would require that an electronic effect (yes, if it does anything it is an electronic effect, not magic) persists across many different types of DAC including both current output and voltage output types with their very different output circuit topologies.Joe Rasmussen said:
When someone thinks he has discovered fairies at the bottom of his garden it can be very unpalatable to be told that the twinkling he sees is just broken shards of glass reflecting sunlight.
I have zero disagreement with you on that.
I have just spent a full half hour (hey, that's an oxymoron) on Jan Didden's website - I will certainly be returning there and read some of the links, but I could not find a link to your article. But I did find Sean Olive's "The Dishonesty of Sighted Listening Tests" and yes, not much to disagree about there either.
In fact, I have encountered this 'bias' before, where clearly an unfashionable piece of equipment was significantly superior to another piece of gear, which had a significant price tag and the prerequisite reviews to back up their bias. I just silently shook my head and I don't claim to be a Golden Ear.
In fact, there have been times when moi was the victim, as I make stuff that get's listened to and of course it can't be as good as the name stuff. Going to audio clubs and demonstrating stuff can be hard to bear - I hate their "shoot-outs" and listening to stuff where the levels are not even close and yet we are to "sit in judgment"?
I remember well in one shoot-out where a particular DAC/Player did not do so well. When one of the guys in the design group did a presenation, he was asked why it did not do so well, he said he was not surprised at all. He said the good stuff often did not do so well when judged this way. But it would satisfy long term.
Well, Stuart, you should remember that, as it was Bruno Putzey and you were there.
Strangely, as you may also remember, much time was spent in getting the levels right and it was blind - but it still didn't work. But then again, remember the speakers? And it was a huge hall and nobody would have heard a proper image, period.
But, I am game, if it could be done with speakers with very high resolution, a room with decent acoustics etc, then I will consider it.
Now I need your article, I definitely want to look at it.
Cheers, Joe
Re Bruno, I have a client in Melbourne about to send his Oppo up for work and he will also send me a pair of NCore 400 Class D amps for a listen. Looking forward to that.
-
Last edited:
Only unfair because it is wrong, you skillfully left out the significant part. He said..
... for an outline of a few of the different ways that ears-only testing can be done, how and why controls are put into place, and a few examples.
At least as helpful as the way you present your ideas.
BTW Here´s the article Joe http://linearaudionet.solide-ict.nl/sites/linearaudio.net/files/LA Vol 2 Yaniger(1).pdf
Jan
Last edited:
http://linearaudionet.solide-ict.nl/sites/linearaudio.net/files/LA Vol 2 Yaniger(1).pdf
The ETF shootouts are, IMO, fun for some, boring and pointless to me. My last ETF, I spent that time drinking with Jan, Morgan, and my wife. I think it was time more productively used, but I wouldn't begrudge the "fun" aspect to those who feel that way. Let's just say that it wouldn't qualify as even a vaguely controlled test.
The ETF shootouts are, IMO, fun for some, boring and pointless to me. My last ETF, I spent that time drinking with Jan, Morgan, and my wife. I think it was time more productively used, but I wouldn't begrudge the "fun" aspect to those who feel that way. Let's just say that it wouldn't qualify as even a vaguely controlled test.
Ehm, the 3.3R are too small to make difference, typical 0.33F caps have ESR in the ballpark of 50-100R, and loading the voltage output of the DAC with 100R+22nF won't help it's internal opamps in any way.
Ah, the 12nF "bypass" of 560R goes straight to ground thru 2.7nF. Virtually loading the opamp's output with 2.7nF - oscillations anyone? Same goes with 100R+22nF, who knows whether internal opamps are stable with such load?
Not to mention of all of these unknown opamp's stability issues driving capacitive load.
Ah, the 12nF "bypass" of 560R goes straight to ground thru 2.7nF. Virtually loading the opamp's output with 2.7nF - oscillations anyone? Same goes with 100R+22nF, who knows whether internal opamps are stable with such load?
Not to mention of all of these unknown opamp's stability issues driving capacitive load.
Sorry, but you have lost me. What does one have to do with the other? And 2 x 3R3 plus 1uF differentially driven does give you close to the predicted response. Both modeled and real measurements back that up.
I admit, that may be problematic and if so, then you will need to increase series R. It will usually show up as noticeable waveform distortion on the scope - then you have to manage that. With modern UGS opamps (don't use 5534) stability will not be an issue.
But I did say, "current" DACs are more predictable, "voltage" less so.
Keep in mind, the examples are 'scenarios' rather than actual designs perse' - they are implementations. Some require more skill than others - I can't pre-predict, but I can only guide.
Re ESR of 0.33F, they are typically rated as 75R and that was indeed kept in mind as it also defines the peak current when they are in their depleted state. Hence this avoids a current spike that might otherwise damage existing onboard regulators. Again, more thought have gone into this that you might realise.
But we can always invent problems ahead of time, and then find our worst fears are not realised.
Cheers, Joe
-
Could you please share the circuit(s) you use in your sims ?
I've done some sims in ltspice and cannot quite replicate your findings. In case 1, the frequency response is indeed independant of the DAC's output impedance due to the virtual ground (mea culpa for not realizing it sooner) but is extremely dependant on the value of the I/V resistor and on the particular opamp used.
I've done some sims in ltspice and cannot quite replicate your findings. In case 1, the frequency response is indeed independant of the DAC's output impedance due to the virtual ground (mea culpa for not realizing it sooner) but is extremely dependant on the value of the I/V resistor and on the particular opamp used.
Firstly, are you suggesting that the explanation for Earthly Sunrises, from which Sunrises on other planets may be logically hypothesized, did not begin with human observation (human perceptual experience) of the phenomena?
Secondly, the human experience/perception of both live music and the electronic reproduction of music is the sole purpose for their being. An accurate scientific explanation of live or reproduced music perception must include all relevant system elements, of which, the human perceptual system is not only key, it is the single most complex element. As such, the human perceptual experience not only can form the basis for valid observations, it is an essential total system element which must be incorporated.
- Status
- Not open for further replies.