Mooly,
Visually these two files show differences. Is this because of the DAC conversions not bring exactly sync'd between the two recordings when you made thrm [Scott please correct my assumption - this may contradict Nyqvist] or is it just due to artifacts in the display? Any other explanations? Can we zoom in to just a small section to get a handle on this?
In term of intelligence, geniuses ARE at one end of a bell curve... "Most people" are not.
That's true, according to one definition genius. But people who score well on IQ tests have other personality traits that are all over the map. And, if someone has a measured high IQ, then the statics that apply to that class also apply to them.
Also, I said that people think statistics don't apply to them, or that they are at one end of a bell curve. It is the former that is most common, and as I said, it appears to be because when people have detailed information about something then tend to ignore or discount coexisting statistical information, which would be incorrect. People often say things like, "I don't need statistics, I already know what I am like." Scientifically speaking, statistics that apply to a class, where an individual is a member of the class, should be accounted for using Bayes Rule, where the statistics give the prior probability.
Not sure I'm following you on that. The image is just one file showing left and right channels.
Mark, a question:
Even if I am statistically a member of a certain group, within that group are variations, and I may actually be an outlier within my group.
But I will never be such an outlier that I would be part of another group, right?
So it's like bell curves within bell curves, sort of?
Jan
Even if I am statistically a member of a certain group, within that group are variations, and I may actually be an outlier within my group.
But I will never be such an outlier that I would be part of another group, right?
So it's like bell curves within bell curves, sort of?
Jan
If I understand your meaning, I wouldn't say someone can be in only one group, because groups are defined by humans with no guarantee that overlap between groups is impossible.
Also, a layer of abstraction can be added to the concept of membership-in-groups with the view taken that the truth that one is a member of one group or another can itself be described as probability function. Of possible interest might be the approach fuzzy logic takes: https://en.wikipedia.org/wiki/Fuzzy_logic
On the other hand, many groups and associated bell curves are orthogonal to each other (as opposed to overlapping, or in the same plane). In that case the bell curves would not overlap, but be at right angles. Sometimes there is some non-zero correlation between bell curves, then they are not completely independent and not orthogonal.
Also, a layer of abstraction can be added to the concept of membership-in-groups with the view taken that the truth that one is a member of one group or another can itself be described as probability function. Of possible interest might be the approach fuzzy logic takes: https://en.wikipedia.org/wiki/Fuzzy_logic
On the other hand, many groups and associated bell curves are orthogonal to each other (as opposed to overlapping, or in the same plane). In that case the bell curves would not overlap, but be at right angles. Sometimes there is some non-zero correlation between bell curves, then they are not completely independent and not orthogonal.
Last edited:
Ahh - ok - I thought it was of two different op amps.
How about taking a snip of the same passage of music on your NJ recording and zooming into it. Suggest something with brushes since it seems this is where people did notice differences.
Is this near enough ?.....“OPhone Free Energy Self-Charging Cell Phone"
I reckon the design is good, really good.
I like the way that the Pono can be plonked down anywhere and the display is always perfectly viewable....and it can be placed/oriented for left or right handed operation, cool/mandatory.
This video review likes the shape and ergonomics but notes letdowns in multifunction menu button and low battery life.
Sound quality is rated as 8/10....I did not search for players with better SQ rating so don't know what is 'better'.
Edit: More info
Dan.
If you have a fractional sample offset there would be problems getting a null without tedious maths.
http://home.agh.edu.pl/~turcza/sr/Splitting the Unit Delay.pdf
Thanks - I'll freely admit the math is a bit beyond me but I'll wade through it - looks very interesting.
IIUC, you may get fractional sample offsets in recordings like this, which in turn might lead to sample by sample differences of the digital words (talking about zoomed right in of course to illustrate the point) but since fs is at least 2x the highest f being sampled, it makes no difference when reconstructed, filtered and output as a bandwidth limited signal.
IIUC, you may get fractional sample offsets in recordings like this, which in turn might lead to sample by sample differences of the digital words (talking about zoomed right in of course to illustrate the point) but since fs is at least 2x the highest f being sampled, it makes no difference when reconstructed, filtered and output as a bandwidth limited signal.
Dan,
The cell phone I have no problem with the look, the Pono I do. What you have to think about is the Pono is supposed to be a portable device that you carry with you. The triangular shape seems to me to be a real problem if you aren't holding it in your hands. I don't think you would put that in your pocket and hanging in a case on your side it would be so bulky. I imagine that the shape was determined based on a set of round batteries internally stacked, I don't know, If that is the case that is just poor design, you can design batteries into flat packages and have a much higher density package than a round battery and not waste the space caused by putting round batteries next to each other. If that isn't the reason for the shape then I just don't get it for packaging reasons. I must say I have never seen a Pono in the wild, never. I see no advantage over a current smart phone for storage of music files.
The cell phone I have no problem with the look, the Pono I do. What you have to think about is the Pono is supposed to be a portable device that you carry with you. The triangular shape seems to me to be a real problem if you aren't holding it in your hands. I don't think you would put that in your pocket and hanging in a case on your side it would be so bulky. I imagine that the shape was determined based on a set of round batteries internally stacked, I don't know, If that is the case that is just poor design, you can design batteries into flat packages and have a much higher density package than a round battery and not waste the space caused by putting round batteries next to each other. If that isn't the reason for the shape then I just don't get it for packaging reasons. I must say I have never seen a Pono in the wild, never. I see no advantage over a current smart phone for storage of music files.
Mooly,
I was another that thought that you were showing a comparison of two devices, never realized that was a right and left channel. I take back my comment about the files being different after that clarification. I can't compare the last set of files you just posted, they look very similar to me.
I was another that thought that you were showing a comparison of two devices, never realized that was a right and left channel. I take back my comment about the files being different after that clarification. I can't compare the last set of files you just posted, they look very similar to me.
I don't think the visual display in Audacity is good enough for the kind of comparisons we are seeking.
I think you have to make tradeoffs here.
Are there any very low noise (lets say <3.5nV/rt Hz or 2pA/rt Hz) opamps that have 100V/us SR's?
I would not countenance a 1 or 2V/us SR opamp, but once you get to 20V/us (line level stage) I think you are in good order.
As always, good decoupling and grounding goes without saying.
Are there any very low noise (lets say <3.5nV/rt Hz or 2pA/rt Hz) opamps that have 100V/us SR's?
I would not countenance a 1 or 2V/us SR opamp, but once you get to 20V/us (line level stage) I think you are in good order.
As always, good decoupling and grounding goes without saying.
You need to be careful and differentiate between raw slew and slew enhancement. The OP275 is actually a slew enhanced bipolar input for instance. 3.5nV with an H bridge input should be easily doable and could easily be >100V/usec.
Really? I've lost count as to how many times I've said this. Slew rate is not a measure of power bandwidth which is the popular misconception. It's how fast an amp recovers From input overload, and has little to do with linear operation. That's why it's tested with a very fast rise time square wave. This input over loads the diff input ( the positive in has full signal while the negative in is still at zero (due to the slight delay of the feedback signal)) I'm not going into detail again. So why is it such an important spec for something that has very little to do with linear operation?
- Status
- Not open for further replies.