Sound Quality Vs. Measurements

[nigel pearson]

If anyone has time would they like to read Naim's new white paper . It is to replace LM317 I think ? Salas might be interested .


http://www.naimaudio.com/sites/default/files/campaigns/dr/naim-dr_whitepaper_may2012_issue1.pdf

 

[vacuphile]

That is pretty much the setup of the Jung/Didden at first glance.

 

[Wavebourn]

Hi Wave I am new to valves and learning , it is about having knowledge rather than loving them . I prefer diesel to steam locomotives so there is no hope I guess ( forget electrics that's class D ) . It has to be said steam comes very close and valves too . The Brits call old radios " steam radios " !?

I found by happy accident the right way to do it and the one you recommend . I had a nasty moment when my head went into reverse gear applied the opposite bias that I intended . As you say it survived . The heat haze coming off of the cathode resistor let me know first .

It is pure coincidence that tubes were used before semiconductors. Otherwise "steam machine thinkers" would consider semiconductors as "steam machines", tubes as "vacuum rocket science".

 

[bcarso]

Not exactly in vacuo but getting there: Ballistic transistor - Wikipedia, the free encyclopedia

 

[benb]

Not exactly in vacuo but getting there: Ballistic transistor - Wikipedia, the free encyclopedia

Wow - think that'll be fast enough for audio?

 

[Wavebourn]

Wow - think that'll be fast enough for audio?

Yes, for digital audio.

 

[tvrgeek]

I seem to remember a story at a Polish mathematician theorized what is basically a FET long before semiconductors were invented. Something like, "if you had a material that behaved like this, you could do that with it" kind of thing.

 

[Wavebourn]

The point is, in order to design semiconductor devices "vacuum step" was not needed. Both could be designed at any time independently. The myth that semiconductors are superior, and superior only, is the result of market economy that needs new stories in order to advertise new production. Solid state diodes were used before tubes. But the industry did not went further than diodes because vacuum tubes were better than point-contact diodes.

 

[DF96]

With modern micro-machining etc. what density of active devices might be achieved in a vacuum thermionic integrated circuit, so how big would a cell phone have to be and what heater power would it consume?

 

[SY]

With micro-machining, heaters are not needed.

 

[nigel pearson]

I seem to remember a story at a Polish mathematician theorized what is basically a FET long before semiconductors were invented. Something like, "if you had a material that behaved like this, you could do that with it" kind of thing.

I had a chart published in about 1908 listing many ten's of semiconductor materials . I think 1880 was when Siemens produced selenium devises commercially ?

I read that a French engineer claimed to have perfected television in the 1880's using selenium cells . Some say Baird knew of this and added amplification . If I am right both worked by optical scanning ?

https://en.wikipedia.org/wiki/Julius_Edgar_Lilienfeld
History of Communications - Historical Periods in Television Technology: 1880-1929
https://encrypted.google.com/patents?vid=1745175&hl=en&lr=all
http://www.computerhistory.org/semiconductor/timeline.html

 

[DF96]

With micro-machining, heaters are not needed.

OK, cold cathodes (field emission?). Does that give enough emission to form a decent space charge so shot noise is suppressed? If not, how do we make low noise UHF/microwave receivers? Also, how does flicker noise scale with device size - could we find (as with GaAsFETs) that flicker noise extends up to VHF frequencies so IF and baseband circuitry is too noisy?

 

[nigel pearson]

What about the DF96 ?
http://www.r-type.org/exhib/aad0032.htm

 

[DF96]

Hey, someone has named a valve after me!!

The DF96 only works in the HF region, so no good for cell phone front ends. It is the same size as other B7G valves so you would need big pockets.

 

[nigel pearson]

What were your parents thinking ?

 

[nigel pearson]

http://www.porticus.org/bell/pdf/brattain_lab_notebook.pdf

 

[SY]

OK, cold cathodes (field emission?). Does that give enough emission to form a decent space charge so shot noise is suppressed? If not, how do we make low noise UHF/microwave receivers?

Paralleling. My buddy who makes these devices can array hundreds of them in an amazingly small bit of silicon. He's using them for some sort of esoteric detector which he can't tell me about.

 

[bcarso]

Paralleling. My buddy who makes these devices can array hundreds of them in an amazingly small bit of silicon. He's using them for some sort of esoteric detector which he can't tell me about.

Sensible. Space charge smoothing is, after all, only a relatively small effect, if still welcome. There are probably also some ingenious ways to make beams more monoenergetic.

The next step will be to utilize entanglement to eliminate cable distortions. And someday, we will have filters and systems with anticipatory responses.

Then my alarm will go off.

 

[SY]

No, in that case, your alarm would go off first.

 

[dvv]

Are you ready to eat your hat, бэби?

Sorry, I don't wear a hat, it impairs natural air flow cooling.

Believe this or not, but I greatly regret we do not live managavly near to each other. I suspect we would spend many a wonderful afternoon nibblig at each other on the subject of trannies vs toobes. We would need power, so we would use a neutral technology device in form of an honest to goodness coal powered grill, permitting electricty only to cool off the beer and/or wine.

We could have others from this forum there as well, and I do believe that would be a good thing. John could brood on the subject of op amps, Wayne could expound opn the virtues of a 0.1 Ohm loudspeaker, and in general, I guarantee we'd all have a good time.