John Curl's Blowtorch preamplifier part II

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Not so much. Ian Masters and Richard Clark are two people who I offhand am aware published their tests, and Masters used a Pioneer (though probably not your model). I'd think that the issue with your Pioneer will be with pathological speakers with bizarre impedance curves. No problem for the almost-as-old Adcom sitting in my living room at the moment.

Yes.

But then it's not really Masters' and Clark's tests we've been waiting all these decades for, is it?

se
 
So who is making audio cables that are designed so poorly they are producing audible differences? They outta be put out of business.

se

Well, if the folks making inferior audio gear have not gone out of business, why discriminate against only one type of manufacturers, cables or otherwise?

Of course, no such manufacturer would ever admit to making inferior gear, but many tests performed independently, scientific or not, consider for example Technics gear to be below par a number of other manufacturers in the same genral price bracket (while they operated, I understand they are no longer in the audio business).

AS for cables, I do not agree they all sound the same, although I cannot say to have heard great differences among them. Enough for me to be able to tell that cable A sounds more open and clearer than cable B when used with my own setup, which is all I'm really interested in. I have neither the tools nor the inclination to use hoursand hours to measure them, since I'm not into writing scientific papers, not to even mention the obvious fact that this is DIY forum, therefore generally orientated towards amateurs.
 
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Don't you see? If we don't know everything then we effectively know nothing. Get it?

The problem is these people are often in complete denial of what is known. Like the fact that human subjective perception isn't the unerring reflection of the objective reality that they make it out to be.

se

That depends on what you are aiming for. I am aiming at what I preceive as slightly better sound, as I am well past big forward leaps. But if you are after all the reasons why because you want to define an ultimate truth and carve it in stone, then by all means, start measuring.

Over the years, I have had the opportunity to agree and disagree with double blind test results as published in magazines, using star studded panels. On a few occasions, I was severly let down by their consensus choices of say amps; I borrow the test winner products, hook them up and hear mediocre sound in about one half of the cases. On considerably more rare occasions, I hear a truly good sound. So what's to trust?
 
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Contrary to Cutzi's assertions, the equivalent of the Cap 'expose' pieces was done by Nelson Pass on why cables are audible. Since then a lot of the cable interfacing and design improved.

And yet NAIM still manage to sell clients their 'special sauce' speaker cables because they didn't fit an output Zoebel on their amplifiers so require inductance in the cables to keep things stable. Their 'new' range has even managed to make a boutique 5 pin din. 18 grand for a 3m speaker cable pair!
 
Already done by F.Toole -- variations above the thresholds he found audible are common in cable/amplifier/speaker interfacing. Where you been? Measured all the time in Stereophile. Just like N.Pass first showed.

Like Nelson Pass fisrt showed? You mean we knew nothing about amplifier output impedance, cable parasitics and dynamic loudspeakers before 1980?

BWAHAHAHAHA!

Only time I see measurements in Stereophile showing loudspeaker response anomalies of a level known to be audible (and John doesn't test into actual loudspeakers, but rather a "simulated" loudspeaker load, which I believe is an 8 ohm resistor in parallel with a 2uF capacitor) is when John's testing boutique amplifiers with pathologically high output impedances, typically tube amps.

se
 
That depends on what you are aiming for. I am aiming at what I preceive as slightly better sound, as I am well past big forward leaps. But if you are after all the reasons why because you want to define an ultimate truth and carve it in stone, then by all means, start measuring.

Over the years, I have had the opportunity to agree and disagree with double blind test results as published in magazines, using star studded panels. On a few occasions, I was severly let down by their consensus choices of say amps; I borrow the test winner products, hook them up and hear mediocre sound in about one half of the cases. On considerably more rare occasions, I hear a truly good sound. So what's to trust?

What I'm aiming for is the so-called "high end" audio industry to finally quit waving their hands and stomping their feet and demonstrate some actual audible differences under controlled listening conditions.

We've been waiting for over 30 years. How much longer will we have to wait? You're always complaining about other people's blind listening tests. When is someone finally going to step up to the plate and show us how it should be done?

As I've said several times already, talk is cheap and talk is all you've got, and it wore thin many years ago.

se
 
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Only time I see measurements in Stereophile showing loudspeaker response anomalies of a level known to be audible (and John doesn't test into actual loudspeakers, but rather a "simulated" loudspeaker load, which I believe is an 8 ohm resistor in parallel with a 2uF capacitor) is when John's testing boutique amplifiers with pathologically high output impedances, typically tube amps.

se
And those, IMO and based on actual testing, are the easiest things to hear. I was in an AES local group lecture in which the speaker of the evening said their class D (perhaps also described as "digital") amp was said by listeners to sound "more tube-like". I recall I couldn't contain myself at that point and argued that they were most likely hearing the effects of frequency response variations due to the high output impedance, in turn due to the fact that the output filter was not enclosed in the feedback loop and had significant impedance.
 
Naim is one of the controversial companies, like Linn, who did both good engineering and hi product promotion, to the point of losing their credibility.
The reason Julian needed an 'inductive' cable was indeed because is quasi-comp output stage needed an output coil or its equivalent to stay stable, like so many amps of the day. (I used a 2uH air coil inductor back then). He found experimentally that removing the coil improved the sound, and he DID design a pretty good power amp, back 40 years ago. If I am not mistaken, Nelson Pass independently found the same thing, and removed his output inductor, and ultimately, I followed suite with the Parasound power amp series, helped by the newer faster output complementary pairs. The difference between the NAIM amp and the Parasound series was that the Parasound could use just about any speaker wire, but the NAIM could not, and required the inductive equivalent of 'zip cord' as the replacement for the output coil that most everybody else used. Julian has been dead for some years now, but I suspect the company wants to keep with the 'special' needs of the NAIM amp, as if it is a necessary evil, when a bit more engineering would find it unnecessary. Going from there, an expensive cable, especially made for the NAIM is useful for the sales force.
 
And those, IMO and based on actual testing, are the easiest things to hear. I was in an AES local group lecture in which the speaker of the evening said their class D (perhaps also described as "digital") amp was said by listeners to sound "more tube-like". I recall I couldn't contain myself at that point and argued that they were most likely hearing the effects of frequency response variations due to the high output impedance, in turn due to the fact that the output filter was not enclosed in the feedback loop and had significant impedance.

HA!

se
 
What I'm aiming for is the so-called "high end" audio industry to finally quit waving their hands and stomping their feet and demonstrate some actual audible differences under controlled listening conditions.

We've been waiting for over 30 years. How much longer will we have to wait? You're always complaining about other people's blind listening tests. When is someone finally going to step up to the plate and show us how it should be done?

As I've said several times already, talk is cheap and talk is all you've got, and it wore thin many years ago.

se

As did your eyes, I made it abundatly clear that I refer to my own experience only, nothing more. Unlike you, I am hoping for nothing from the "High End" because I thinl it's dry as a desert by now, it's mostly sales talk and I find a lot of disappointment these days. It's mostly about chasing idle millionaires these days. Obiously, it can't do much better than that, at least en masse, and there are still a few people left there wanting something better, but they are obviously more exceptions than rules.

I am not complaining about double blind group tests, no need, I've understood long ago that they mean little in practical terms to me. So in fact, I am not complaining because I never expected much from them. They seem to mostly matter these days so disgruntled people like you can say it was not done properly for one reason ior another. In short, they serve as an excuse for those times when something fails to live to its ads. Exactly what is to be their result, to tell us that A sounds better then B? I don't need others' ears to tell me what sounds better to me.

As for talk being cheap, well, we've had a practical lesson on that in your quasi scientific scribblings, pages and pages of it. Most of which boil down to personal attacks. Everybody's hand waving at you, you poor man, yet I saw no links to the hard science papers you published. Nor will we, methinks. For $194 a pop, you do have explaining to do.
 
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As did your eyes, I made it abundatly clear that I refer to my own experience only, nothing more.

Then why did you post it if it had no relevance to the discussion at hand?

Exactly what is to be their result, to tell us that A sounds better then B? I don't need others' ears to tell me what sounds better to me.

That's preference testing. No ones arguing as to what anyone's personal preferences should be. Again, this has no relevance to the discussion at hand. So where is this coming from?

As for talk being cheap, well, we've had a practical lesson on that in your quasi scientific scribblings, pages and pages of it. Most of which boil down to personal attacks. Everybody's hand waving at you, you poor man, yet I saw no links to the hard science papers you published. Nor will we, methinks. For $194 a pop, you do have explaining to do.

What explaining do I have to do? I'm not making any unsubstantiated claims. So what hard science papers do I need to be publishing? You seem to be arguing against things I've never written.

se
 
That's all you get, Brad. What else did you expect from a cable knitter?

So personal attacks are ok with you? And what more should I have said to Brad? He told an amusing tale, and I laughed in response. What would the appropriate response have been? Sorry, but you just don't seem to have a terribly firm grip on reality.

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Christophe,
Your right, I guess I would also fit into the third group, I believe in the science and also trust that I can hear something amiss. In some situations science takes the lead and in others intuition shows the way. I think it is easier for me to work on the mechanical speaker side of things. physics don't lie over on this side of the equation and measurable results are easily seen when making a change in FR or phase response.
 
So personal attacks are ok with you? And what more should I have said to Brad? He told an amusing tale, and I laughed in response. What would the appropriate response have been? Sorry, but you just don't seem to have a terribly firm grip on reality.

se

Don't switch trheses here, you're the one with a grudge. To you, NOBODY is saying anything meaningful, except yourself, of course, you are here to debunk everyone and everything anyone says.

For God's sake, just look at your posts! Immediate putdowns for everyone and everything.

As such, you are not worth wasting any more time on.
 
You may be confusing the use of a 5.6V zener and a forward-biased small-signal diode, the prototypical 6.2V reference combination with compensated tempco, with the single zener ~zero tempco, which occurs more in the vicinity of 5V (I found a 1N5231B usually close to 4.78V, although this entailed an uncomfortably low Iz sometimes).

Although the buried zener is cited for good long-term stability, it is also mentioned as lower noise, for example:
LM199 | Shunt Voltage Reference | Voltage Reference | Description & parametrics

excerpt: "Further, a new [sic] subsurface zener structure gives low noise and excellent long-term stability compared to ordinary monolithic zeners".

As to zener noise vs. voltage, Motchenbacher and Connelly advise the use of zeners in the "true zener" (internal field emission) voltage range, e.g. not in the higher voltages that depend on avalanching. See their example:

not quite, there is a very broad minima of tempco around the 6 volt region.
there is also a clear maxima of zener noise near the 6.2 volt region. The only advantage of a buried zener is a very much reduced 1/f noise.
Your 3.9V zener was 11nV root Hz, the LTZ1000 is 50nV root Hz, 6.3 v zener and 600 mV base voltage in use giving approx a 7 V reference.
There are some Russian Zeners with a zero tempco like the 1n829, but with a 9 Volt zener voltage, I dont know how those are done.

Around the 7-12 Volt region you will find zeners with about 20nV root Hz. and just try using an ordinary 6.2V zener at 20uA, possibly 1uV root hz!
 
Don't switch trheses here, you're the one with a grudge. To you, NOBODY is saying anything meaningful, except yourself, of course, you are here to debunk everyone and everything anyone says.

Oh no, there are plenty of people here saying meaningful things.

For God's sake, just look at your posts! Immediate putdowns for everyone and everything.

Again, you don't seem to have a terribly firm grip on reality.

As such, you are not worth wasting any more time on.

Promise?

se
 
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