John Curl's Blowtorch preamplifier part II

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That's a very good article in a rather uneven edition of that book. I particularly appreciate his section about telephone "hybrids", which can be difficult to find and are immensely clever circuits. As so many nowadays are eschewing land lines and have little experience with full duplex telephony, the knowledge will likely become increasingly arcane.

Oh don't get me started on that. They'll get my full duplex land line when they pry it from my cold, dead hands. :D

There are some dear friends of mine that I simply can't stand to talk to because of their crappy-*** cell phones and Skype connections. But that's the only choice as they've dropped their land line service.

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Oh don't get me started on that. They'll get my full duplex land line when they pry it from my cold, dead hands. :D

There are some dear friends of mine that I simply can't stand to talk to because of their crappy-*** cell phones and Skype connections. But that's the only choice as they've dropped their land line service.

se
Steve do you remember the scene early on in Spies Like Us, when "Emmett Fitz-Hume" is giving a press conference, and when the questions get a trifle "hairy" simulates an intermittent in his mic? I feel sometimes similarly disposed to attempting such a subterfuge with people and their nasty cells and portables.

Even people who intensely dislike Chevy Chase should be able to appreciate that scene, I think.

"Unch time, gotta go."
 
Steve do you remember the scene early on in Spies Like Us, when "Emmett Fitz-Hume" is giving a press conference, and when the questions get a trifle "hairy" simulates an intermittent in his mic? I feel sometimes similarly disposed to attempting such a subterfuge with people and their nasty cells and portables.

Even people who intensely dislike Chevy Chase should be able to appreciate that scene, I think.

HA!

I basically mimic that when I'm explaining to my friends why it's so !@#$% frustrating to try talking to them.

And with cell phones, because they're digital, when things start going bad, they just go completely to !@#$%. With analog, you can still communicate effectively with a surprising amount of noise on the line.

I've a Western Electric CD 500 here that was built in 1957 and as far as I can tell, has never been refurbished. It sounds better than most of my friends' cell phones.

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And with cell phones, because they're digital, when things start going bad, they just go completely to !@#$%. With analog, you can still communicate effectively with a surprising amount of noise on the line.
Of course, there are some nice parallels there with the whole issue of "digital" vs. "analogue" music sound. Except, the digital "badness" occurs at just a sufficiently low level to make it very hard to grab hold of the blighter when staring at some instrument needle - but the ears have no trouble picking it ...
 
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Of course, there are some nice parallels there with the whole issue of "digital" vs. "analogue" music sound. Except, the digital "badness" occurs at just a sufficiently low level to make it very hard to grab hold of the blighter when staring at some instrument needle - but the ears have no trouble picking it ...

Bu... ...shimp... ...spi... ...ock.. ...fliff... ...mo... ...ank... ...ham... ...thee... ...frish... ...nop...

...otta go.

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Well, I wish that I could help, but I can't. Most of these topics are known and extensively sourced in the archives. For example, practical tube noise is extensively discussed in Skov's AES article that I put a a few pages up, as well as Barkhausen noise and even practical examples are worked out. But you have to read the article, and most here, have no access to it, nor any questions about the pages that I put up.
 
You know, I reckon the trouble with digital is this 1's and 0's idea ... you know what they say about nature abhoring a vaccuum, those zeros are upsetting the gods ...maybe, maybe what we really need is Short bits and Long bits ... yes, yes, that's it, both things are real 'things'! It will more warm, more tube like, why, it will be more SET like ... and, and, I'll call it MorSET Code, 'cause that's what it all about ...
 
For example, practical tube noise is extensively discussed in Skov's AES article that I put a a few pages up, as well as Barkhausen noise and even practical examples are worked out.

Skov does a nice job of outlining the elements as they were understood at the time. There's a lot more complete treatments available today, but this is still a good intro and is sufficient for understanding the vast majority of basic noise calculations in audio. It also provides the basic information to debunk the idea that Barkhausen noise has any significance in audio input transformers, phono cartridges, or playback tape heads!

The one extra topic I'd recommend to diyers who are trying to design for low noise using small signal transducers is the Q transform method, which greatly simplifies the calculations.
 
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