John Curl's Blowtorch preamplifier part II

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In university, most of the students from far away area rent a room near campus. I have one room where when I rent it the owner asked me not to stick any nail on the wall and I said okay.

So when my close friend came by I told him that "I need a hanger but unfortunately I already promised the room owner not to stick nails on the wall" then I told him that I wanted to go out for a moment.

When I came back, the hanger was already done. Perfect communication as expected. But when I think about it, what is the difference with me directly breaking the promise. But legally I didn't.

Actually you did and added another "Conspiracy!" I trust you patched the hole before leaving.

There are special adhesive tapes that can hold a hanger quite securely and when you leave they can be completely removed without damage to the wall by pulling the tape off in shear mode.
 
The clue is in the name. A 'hi-fi' preamp is one whose output closely resembles an amplified copy of the input, apart from well-placed LF and HF filters.

My words might be hard to understand, but I usually don't use clues (as I'm a "direct" person). My question about OPA627 vs DCB1, and from your clue I get it that OPA627 is more "hi-fi" to you than DCB1.

Measurements for the purpose of looking cool are likely to be either irrelevant measurements or badly-performed/analysed measurements. Much better to measure as an aid to debugging, or to reassure that theory has been correctly applied and so measured behaviour corresponds to calculated behaviour.

I understand your point (which is relevant especially when you do a critical research with circuit).

Many times I have experienced situations where I found measurement is not so useful (for my purpose), unless I need to tell people about it (so you speak with the same language). It can be because no accurate measurement is possible or that the measurement means a little or it is just a waste of time (e.g. your ears can predict the measurement result well).
 
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Many times I have experienced situations where I found measurement is not so useful (for my purpose), unless I need to tell people about it (so you speak with the same language). It can be because no accurate measurement is possible or that the measurement means a little or it is just a waste of time (e.g. your ears can predict the measurement result well).

Or you don't know what your are doing.
 
Actually you did and added another "Conspiracy!"

Yeah, I wouldn't do it if I could think the way I do now. I didn't feel guilty back then :eek:

I trust you patched the hole before leaving.

Not at all. I'm lousy with verbal, but very good with non-verbal communication.

There are special adhesive tapes that can hold a hanger quite securely and when you leave they can be completely removed without damage to the wall by pulling the tape off in shear mode.

It's a hanger (with many hooks) where you can hang your clothes. No adhesive tape can do that. At least I didn't know any.
 
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Fine differences fall at or just below the threshold of audibility and I think that's what we are discussing here,...

But in reality you just believe that the differences fall at or below the threshold of audibility.
It might be a plausible hypothesis, based on the known thresholds for single parameters, but in fact for complex stimuli diverging in a multitude of parameters there is no threshold known.

.... and that's where DBT of ABX testing can help determine the limits of our perception easily and with a statistically significant result.

To be double blind is usually part of the scientific requirements but there is no need for using the ABX protocol. It is not that easy; a lot of tests are unfortunately methodologically flawed.

My wife was always doing stats when she was studying and subsequently teaching/lecturing - so in the psychology profession, and especially when studying human perception, you always test a hypothesis statistically. There is no wiggle room.

But the data/publication was all that was asked for. Exists hard evidence already or is it a hypothesis that should be tested?

So, with audio, let's not make claims that under scientific scrutiny don't stand up.

Absolutely; we all tend to jump to conclusions.....

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Remember the Carver test . . .

I do remember it; there was no sound controlled listening experiment involved at all. :)
 
If you are trying to have a rational discussion then hiding the point between the lines marks the fact that you are not seeking a common understanding with others just a reinforcement of your beliefs.

No, reading the lines means to find out the real intention. Because It can be "hidden", not intentionally. But some people lose focus and try to "attack" the grammar, the shoes, the shirts, whatever but the point. Not for logical reason, but psychological.
 
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No, reading the lines means to find out the real intention. Because It can be "hidden", not intentionally. But some people lose focus and try to "attack" the grammar, the shoes, the shirts, whatever but the point. Not for logical reason, but psychological.

Most people here are trying to be very clear. YOU are the one obfuscating things. When people are clear there is nothing to read between the lines.
 
Why do you guys waste our time by insisting that we cannot hear audio differences that are not easily measurable? What sound quality that an audio reproducer has, can be consistently determined by a good audio listener. Of course, many don't care that much about subtle differences, so they will accept mid-fi and often even table radio quality. This is not the people that should lead this discussion.
In reality, we hear what we hear, however, we CAN be deliberately fooled or confused by a psychological test set-up, and that is what is wrong with ABX testing. We discussed this in detail 35 years ago in TAA. We had Ph'd's and other audio experts commenting on both sides even then. There is no resolution, IF you don't believe that the differences in audio quality, for the most part are not real.
 
Because, evidence? Not important for hawking stuff in your market niche, admittedly, but some of us care about actual sound, not moving product.

Of course, many don't care that much about subtle differences, so they will accept mid-fi and often even table radio quality. This is not the people that should lead this discussion.

And none of them are, other than the one guy who uses computer speakers and a TV set for evaluation.
 
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