I don't know who writes Jack's marketing ads, maybe Jack does, himself. They are over the top often. However, Jack believes in the effectiveness of his devices, and I do too, at least the ones that I have tried or had demonstrated to me. Sometimes they work to make the sound sound worse, but that is not often. Usually, they make a small improvement with a highly tuned audio system, and they are based on technology that usually cannot be made in a garage, but in an advanced electronics factory, any more than a transistor or IC can be fabricated in a garage. The QSE devices are an exception to this pattern, being some sort of COATED aluminum foil, in a wooden case. Scott, it is the COATING that has to be analyzed, not the wrapper.
John,
What was the silver wire that you found you liked best?
Do you have a brand name for it? A buddy of mine has
a storage place with various spools of the old stuff.
If you let me know I can check or test when I get my UPD
running again.
I've heard a difference in capacitor and resistors. Some I like
some I won't use, or will only use in cert ain locations.
And it's not just me either, the folks who use the amps
I've done for them can hear a difference too.
Some resistors can't be used in first stage/grid stoppers, for example.
They are too bright and pick up static. I kept thinking it was the new
capacitors I put into the circuit. After a few amps I determined it was
the High End name brand metal film resistors. Shame on me, figured
it out just in the nick of time.
I guess it depends on what you are doing, have a log of what you've done,
what your customers say, and can hear a difference.
When I had my maggies, I think the 3.2s, I used the high end Mills resistors for the crossover.
I had from 1.0 ohm to 3.0 ohm with some in .2 ohm steps. I'd put them in and listen,
and for some reason the 1.0 ohm was okay, 1.2 ohm never sounded good but the 1.6 ohm
or 2.0 ohm sounded much better. The 3.0 ohm weren't that good. It turns out once I got
to measuring the resistors, the 1.2 ohm were actually measured 3.0 ohms
and it was not so great with the crossovers.
Anyway, enjoy, believe it or slurp it!
Cheers,
What was the silver wire that you found you liked best?
Do you have a brand name for it? A buddy of mine has
a storage place with various spools of the old stuff.
If you let me know I can check or test when I get my UPD
running again.
I've heard a difference in capacitor and resistors. Some I like
some I won't use, or will only use in cert ain locations.
And it's not just me either, the folks who use the amps
I've done for them can hear a difference too.
Some resistors can't be used in first stage/grid stoppers, for example.
They are too bright and pick up static. I kept thinking it was the new
capacitors I put into the circuit. After a few amps I determined it was
the High End name brand metal film resistors. Shame on me, figured
it out just in the nick of time.
I guess it depends on what you are doing, have a log of what you've done,
what your customers say, and can hear a difference.
When I had my maggies, I think the 3.2s, I used the high end Mills resistors for the crossover.
I had from 1.0 ohm to 3.0 ohm with some in .2 ohm steps. I'd put them in and listen,
and for some reason the 1.0 ohm was okay, 1.2 ohm never sounded good but the 1.6 ohm
or 2.0 ohm sounded much better. The 3.0 ohm weren't that good. It turns out once I got
to measuring the resistors, the 1.2 ohm were actually measured 3.0 ohms
and it was not so great with the crossovers.
Anyway, enjoy, believe it or slurp it!
Cheers,
SyncTroniX, you and I could have a pleasant conversation together, and perhaps learn something new from each other. I have heard the same sort of thing from other subjective listeners. For example, 8uF Wonder Caps (from the old days), sounded better than 5 or 10uf caps from the same manufacturer. How should I know, but I do have 8uf caps in my inventory. No use taking a chance on another value. I have perhaps several thousand 1% resistors that I don't know what to do with. They are just the wrong brands, that's all. I do use some of them for just prototyping for measurement only, but for a final product, I never use them. Why take a chance?
Over the years I have learned about physical differences in the construction of capacitors, both in material and fabrication. Most serious hi end manufacturers find that the same brands are what each other use, because they found them to sound best. This happened with Charley Hansen and me, where we found that Reliable RT polystyrene caps sounded the best. We compared notes years after independently finding this to be so. Coincidence? I don't think so.
Over the years I have learned about physical differences in the construction of capacitors, both in material and fabrication. Most serious hi end manufacturers find that the same brands are what each other use, because they found them to sound best. This happened with Charley Hansen and me, where we found that Reliable RT polystyrene caps sounded the best. We compared notes years after independently finding this to be so. Coincidence? I don't think so.
And also the very first step that should be done.
It's the keys-under-the-lamppost syndrome: 'figuring out which reports are reliable is nigh impossible, so let's skip that step'.
Jan
It is never independently of course. It is very clear from how observing the world that hordes of people latch on to whatever a single person started. It's called a trend, a fad, etc.
As Anatoli France once famously commented on his nation's state: 'if 50 million people believe something wrong, it is still wrong'.
Jan
I have this:
Fairchild AN-4161 Practical Considerations of Trench MOSFET Stability when Operating in Linear Mode
NASA/TM-2010-216684 Power MOSFET Thermal Instability Operation Characterization Support
8th THERMINIC Workshop 1-4 October 2002, Madrid
Improved electro-thermal simulation of power devices
Send me a PM if you want a copy.
Jan
It may seem that way, but likely availability bias at work:
https://people.umass.edu/biep540w/pdf/Tversky availability.pdf
For observations in more obscure cases you probably never heard about, it's probably more likely for independent observations to occur. On the other hand, for well known cases that get discussed over and over in snake oil threads, those are things tend to come more easily to mind.
Since its easier to remember examples of instances you have heard about than not heard about, that can make it seem like more easily remembered examples are always the case.
For example, lots of people may have heard other people's opinions about individual components such as capacitors (which may actually sound different, as it happens), but fewer people may have heard about the sound a whole product that just came out and only a few people have had an opportunity to listen to. How about a Cranesong Quantum? Does everybody already share the same opinion of what one sounds like? Probably not, but if you didn't think of that one, it wasn't available to you as an example when you formed your opinion that independent observations never occur.
Mark, interesting find, thanks.
But I am confused a bit by this passage:
First, set up a given MOSFET with a constant Vgs, similar to that used in your linear circuit and measure Id. Then simply heat the device or observe under self-heating. As the device warms up, the drain current should drop. This is a sure fire indicator that the device is NOT in thermal run-away. If you observe the opposite effect, which is to say that current increases with temperature, this will be problematic in linear mode.
I always thought that each MOSFET has a particular Id value when it changes from pos to neg tempco, and this is normally indicated in the data sheet. Is that different from what they mean here?
Jan
But I am confused a bit by this passage:
First, set up a given MOSFET with a constant Vgs, similar to that used in your linear circuit and measure Id. Then simply heat the device or observe under self-heating. As the device warms up, the drain current should drop. This is a sure fire indicator that the device is NOT in thermal run-away. If you observe the opposite effect, which is to say that current increases with temperature, this will be problematic in linear mode.
I always thought that each MOSFET has a particular Id value when it changes from pos to neg tempco, and this is normally indicated in the data sheet. Is that different from what they mean here?
Jan
No one ever said capacitors couldn't sound different. Self even puts measurements showing the distortion effects of the wrong capacitor in a circuit. It's just that the 'wider soundstage and lifted veil' brigade don't seem to understand that mass produced off the shelf stuff is more likely to be better than their hand rolled by virgins ultra-hyper-audiocap.
If it sounds like anything its not neutral so of no interest to me anyway. How you jump from silver cable to a studio AD/DA with added DSP to add distortion to taste is a little odd. However to answer you, look in this forum for the number of topics where people ask about the sound of X vs Y. Of course unless they are looking for reinforcement of their decision they will be disappointed.
Comes back to, in the 20-500ft of cable your music has passed through before it gets to you, how you will 6" of magic silver really make much difference esp as all it does is reduce the resistance of the wire a bit. Nobel prizes to those how can find that one out!
What the hell with those you call in a scornful way the "wider soundstage and lifted veil brigade" ?
To talk about the sound of an hifi system is exactly like talking of taste about wine and kitchen. So strange in your mind ?
What can be said about the people, (you ?) that buy their audio gears looking only at distortion numbers on the data sheet like those who buy industrial food looking at the composition on the can ?
I'm not sure to accept their invitation to dinner ;-)
Between the "hand rolled by virgins ultra-hyper-audiocap" and those cheap electrolytic ones that had bring failures in the mother boards of so many computers, there is a large place for good enough industrial components at a *reasonable* value for money.
Depending on the money you have and the level of quality you want to reach, your target on the curve will not be the same. Something to say against people with different targets and ressources than your ?
I would be more interested in reading your comparative listening comments and measurements of different brands of resistances and capacitors than reading these incessant and sterile jokes about the superstitions of the so-called audiophiles brigade. Because it does not help anyone and it is -sorry to say this- boring.
Something like this: Picking Capacitors - Walter G. Jung and Richard Marsh
Of course, *I* will never buy these magic cables which are worth the price of all my equipment, do you really think that the members of this forum are so stupid and unwashed ?
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Jan, I think maybe they mean if you want to use a device that isn't characterized for the exact operation you have in mind on the data sheet, you can observe it at your proposed operating conditions to see if it is thermally stable or will run away.
EDIT: There may also be some variation from device to device, so it could be possible to test individual devices to see if you can find one that will work. Similar to how people otherwise sort parts for specialized circuit needs.
EDIT: There may also be some variation from device to device, so it could be possible to test individual devices to see if you can find one that will work. Similar to how people otherwise sort parts for specialized circuit needs.
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Bill:
Actually, someone in the forum did say capacitors can't sound different, but he was corrected. Doesn't matter though, it was just an example. We could pick another one, but I didn't want to use silver wire. It might be too polarizing in the heat of discussions.
Also, if you think people are not listening independently, and I agree often they may not be, then some kind of blind testing would be in order. I think that's what I said before, I just said it should be a blind test that people can use without impractical amounts of training which would probably be necessary for confirming audibility of low level differences with some of the ABX tests currently in use. Should be easy to make a few improvements to the tests though. That's what I was trying to say.
The other thing I was thinking about works something like this: I have seen cases where two mastering engineers meet in the hallway somewhere and both describe what a piece of gear sounds like to them. If they are people who don't hang out on forums or read trade rags, which not everybody does (hard to believe around here!), their opinions may be more likely to be trustworthy. Still might want to blind test them, but at least you might think it worth the effort to go ahead and do it.
Actually, someone in the forum did say capacitors can't sound different, but he was corrected. Doesn't matter though, it was just an example. We could pick another one, but I didn't want to use silver wire. It might be too polarizing in the heat of discussions.
Also, if you think people are not listening independently, and I agree often they may not be, then some kind of blind testing would be in order. I think that's what I said before, I just said it should be a blind test that people can use without impractical amounts of training which would probably be necessary for confirming audibility of low level differences with some of the ABX tests currently in use. Should be easy to make a few improvements to the tests though. That's what I was trying to say.
The other thing I was thinking about works something like this: I have seen cases where two mastering engineers meet in the hallway somewhere and both describe what a piece of gear sounds like to them. If they are people who don't hang out on forums or read trade rags, which not everybody does (hard to believe around here!), their opinions may be more likely to be trustworthy. Still might want to blind test them, but at least you might think it worth the effort to go ahead and do it.
Virtually all of these article mixed in cases of grossly misapplied capacitors to make the results measurable. There was an unfortunate spin to find boggy men rather than do engineering. There are modestly priced commercial capacitors that show no measurable distortions for almost any socket, Samuel Groner has the most agenda free set of resistor and capacitor measurements.
I also showed JC and Walt how to use a bridge to extract the Pease model of DA (an ordinary ladder of ideal R's and C's), no fun in that.
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Yes sure, I know. But if the datasheet shows thermal coefficient xover at say 2A Id, do I then still have to do this test with a design Id of say 500mA? See attached example. Doesn't make sense.
But to be sure, I will do it in my app with the very high voltage MOSFET.
Edit: I am wrong - this is happening below the xover to neg tempco....
Jan
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