The Black Hole......

For example (screenshot taken just now).
 

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A thank you to Allen and all the other moderators who may have participated in this forum software upgrade. As a forum owner myself I know that things can go sideways pretty quick during a software upgrade, I say well done on this one!

Cheers!
Howie
 
Conversion efficiency, I will remember that. Yes, a paradox it seems. That 1000mW and 62.5mW just doesn't look right, but when understood, it does. I think that is what Jan can't get his head around? Only he could say and I will not be guilty of putting words in his mouth.

If I may just put a cap on that. The real value in conversion efficiency is from 1000mW (one driver) down to 250mW (four drivers) which only then becomes 62.5mW - or else it would come across as too fantastical. The conversion efficiency is between 1000mW and 250mW and no more. It is just that the 250mW is shared (divided) by four drivers to 62.5mW, but it still remains 250mW dissipated in the voice coils.
 
Every time I turn around there is something new to get used to. It was more fun when I was 20. Not so much at 70.

:geezer:
I feel your pain, a Synology NAS update resulted in no PC pre-Win10 being able to access network data without a patch....although the biggest pain I have right now (off-topic pending, run for your lives!) is refurbishing a 50 year old Drake R-4B HF receiver with a Linear PTO (Permeability Tuned Oscillator) which will randomly pop back and forth several hundred cycles (while tuned to 5 MHz) with concurrent internal B+ rail changes. No parasitic oscillations are showing up on the output. After replacing the Zener I am suspecting leaky ceramic bypass capacitors. It sounds like a no-brainer simple fix, right?...until you see what physically accessing the PTO PCB entails...
And for your daily amusement I have attached a scan of the PTO schematic which was shoe-horned into a small corner of the schematic page...I had to redraw it to be sure of what I was working with...

I now return you to your audio subject du jour...
Cheers & 73,
Howie / WA4PSC
 

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A more AF-oriented post to compensate for the RF post...
https://phys.org/news/2021-12-physicists-special-transverse.html
I have seldom read a paper containing so many buzz words, I looked for an April 1 posting date, but I see some serious problems with their postulate. To begin with there is indeed shear as defined by classical physics in both gases and liquids. It is the basis for injection molding, hydrodynamic bearings using both liquid and gas, and refraction of wavefronts.

Maybe someone a lot smarter than I am could see their point, perhaps seeing through potential translation (pun intended) errors?

Cheers!
Howie
 
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