PMA said:
Yes, I concede. It was "proven true" by a whopping 0.0025% difference.
The way John was using CAPS in his original post though, you'd think he was talking about something that was actually significant.
se
You are off by a factor of 10 in absolute magnitude, and most people presume that distortion drops with lower level. Not so with transformers. Now, everyone, think of dynamic DC offset inherent in the asymmetry of the audio signal passing through the transformer.
Andre Visser said:
Here is the DLP (Deviation from Linear Phase) for the JT-11P-1:
An externally hosted image should be here but it was not working when we last tested it.
se
john curl said:
Yes. Just think of it. Obsess over it. Imagine just how frightening it is. How it could be lurking around any corner or maybe even hiding under your bed when you go to sleep at night. It's lurking in the shadows, just waiting for an opportunity to rip your ears to shreds when you least expect it.
Don't ever attempt to confront it and meet it on your own terms and make up your own mind. The numbers don't lie. They prove conclusively that it's it's killed before and it will kill again. You'll just be another in a long line of innocent victims who thought they knew better.
So play it safe. Stay well away. And whatever you do, don't...
OH MY GOD! THERE IT IS!
AIIIIIEEEEEEEEEEEEEEEE!!!!
An externally hosted image should be here but it was not working when we last tested it.
To overcome the low level hysteresis problems HF biasing (to keep the core in "motion") has been suggested and succesfully used. I just can't find the reference right now...john curl said:
- Klaus
john curl said:
John I asked you before not to mix my day job with my hobby. IC's can't use 'em, three leads good eight leads bad!
From some of the posts I would suggest tis the grey matter in cetain heads that is unstable not the circuits per say.
That fact this is in full view of the public is scary.
You guys need to get some fresh air and see the light of day.
iMac
That fact this is in full view of the public is scary.
You guys need to get some fresh air and see the light of day.
iMac
Macka, I might agree that we need a break, but I hope that you learned something from all this. If not, then it is you who has the biggest problem. You have to see below the aggressive discourse and learn the material. Many people here have some poor ideas about transformers. To some, they are obsolete, like tubes. To others, they are the saving grace of their hi fi's, and they must, therefore, be virtually perfect. Neither view is really accurate.
Eureka! I have found one example of Deane's old measurements. It is for the JE-16-A microphone input transformer. Distortion at 20 HZ and -30 dB below OdBV is 0.1%, dips to .03% at -10dBV and back to .1% at 0dBV. Let us praise the late Deane Jensen, an honest man.
john curl said:
Mmm...
You're absolutely right. But then straw men aren't intended to be accurate in the first place, are they? Makes it much easier to set fire to them that way.
se
john curl said:
First, what is the source impedance given for that measurement? And are the levels really in dBV or dBU?
Second, there is currently no JE-16-A in Jensen's catalog. It is however a JT-16-A and here are the measurements for THD+N versus input level at fixed frequencies:
An externally hosted image should be here but it was not working when we last tested it.
What evidence do you have that these measurements for the JT-16-A are dishonest, John?
Which, by implication, means that Bill Whitlock is a dishonest man.
I'm no lawyer, but if I were in Bill's shoes, I would most definitely consider the claims you've been making about Jensen Transformers libelous.
se
Let me just say that I trust Deane Jensen's measurements first, because he designed the transformers. Often the designer is more honest with his design than than people who market it. This difference in measurement is most probably test conditions. What are Roger's? Negative Z? O drive Z? infinite load? Please specify and we can get to the bottom of this.
john curl said:
What you said was "I KNOW what I have seen with my own eyes, and watched it be buried over, in the following decades." Yet you have provided no evidence of anything being "buried" or that Jensen Transformers is anything less than honest with regard to the specifications and measurements of their transformers.
And FYI, I'm told that most of Deane's transformers were designed by Ed Reichenbach, formerly of Altec, and later of Richenbach Engineering.
Who the hell's Roger?
All you have to do is take a look at the JT-16-A's datasheet.
Source impedance is 150 ohms. Load is 6.19k in parallel with 4.53k/620pF.
se
macka said:
Hi
Don't be rude. I lerned lots from the cerebrally intact audio legends about cryoing/ freezing boards and resistors for better sound.
My only complaint is that now I don’t know where to put my peas.
Beep.
Glen, that was certainly enlightening.
Sorry folks, meant Bill rather than Roger. Just got the name wrong. Still, I have graphs that back up my EVERY WORD. It would be interesting if the Jensen transformers suffer from this problem, what about other transformer manufacturers? Does negative Z drive fix this problem?
Sorry folks, meant Bill rather than Roger. Just got the name wrong. Still, I have graphs that back up my EVERY WORD. It would be interesting if the Jensen transformers suffer from this problem, what about other transformer manufacturers? Does negative Z drive fix this problem?
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