Could we say, not exactly bilateral? Doesn't mean it's directional like a diode. What if Z0 is not a constant? Cable tightly coiled at one end? Termination reflections unequal due to mechanical tolerances at connectors? Actually, that can be a problem. There are some ground flat and finely polished mating surface connector designs available for RF.
Scott,
As usual, the open issue on DA is when using the music as an AM carrier what does DA do to the modulation. My feel is that having different time constants makes the process create artifacts that are perceptable.
As to your desire to use one of the possible definitions of linear that differs from the one I use is interesting. I was to me clearly describing the graph or oscilloscope display, you are using a different definition that is inadequate for human perceptual processes. In your case of an RC filter there is a simple experiment many can try.
Use a 2 uF capacitor in series with your signal source (CD Player) shunt the output of the capacitor to ground via a 10,000 ohm variable resistor. From the junction of the variable resistor to the preamplifier input pass the signal through a 100,000 ohm resistor. Now place a switch across the capacitor.
All you have to do is lower the variable resistor's value while you switch the capacitor in and out of the circuit until you can hear a difference. You can try low and high DA capacitors. You can even try an electrolytic.
A simple audio test most here can do. Even you! (But others will probably hear the difference well before you do.)
That will illustrate both what bandwidth limiting of low frequencies has on audio and the difference between low DA and high DA capacitors.
The NOS were in appearance like paper in oil cans.
Check for the price of the modern production
https://escies.org/download/webDocumentFile?id=60900
George
Yes, l was thinking the same thing (about my car, not yours). 🙂 Also, his Roadster in my garage. 😎
Ed if you want to talk about linearity, either describe precisely what you want to say or use the formal language. Assuming we are going to use your personal lexicon is counterproductive.
You almost scared me, but then I thought about this.
AK4497EQ in dual mono mode has better than 115dB distortion. It might be the best commercially available DAC chip at the moment.
https://www.akm.com/akm/en/file/datasheet/AK4497EQ.pdf
p. 97 shows how to get the goodness out: in two of the AK suggested alternatives, each output connects through a 100u electrolytic to the outside world, a S-K low pass filter to be precise, loaded by 10k in the audio band.
Asahi Kasei is racing against Sabre to get the best measured performance to the market. Since it would have been trivial replace these 100u electrolytics by servo's, but AK didn't, I feel a great sense of relief. They must believe that a big, high value electrolytic cap, well placed in the signal chain, doesn't matter. And so do I.
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Certainly simplifies layout, to boot. Plus there's been enough measurements of large bipolar (or polar in series back to back) electrolytics that require distortion amplifiers to say that, well, the good ones (E.g. something like Nichicon ES) are pushing the limits of many a distortion magnifier. Not exactly a rate limiter.
They say the car will continue to accelerate up to 39,600Km/h... If no cop, hidden in Van Allen's belt, stops Starman with a radar.
The most sad, I believe, is that this car will be in a very good shape in 100 Years. No wear and no corrosion in the space. A perfect vintage car for ET.
Lots of high energy photons are going to degrade the plastics even in the absence of oxygen.
Vacuphile and DPH: Please report for immediate burning at the stake for heresy! 😛
Tonight my quest for real dynamics moved forwards as my copy of Hank Jones Arigato turned up. This is currently 3rd on the DR range database Album list - Dynamic Range Database . #1 I don't want and #2 is in the post. All for research purposes, but the Jones album is some nice Jazz and I have to say, VERY realistic. Unprompted, wife on sofa said that 'it's wierd, but sounds like they are in the room with us'. The way it's miked Jones' piano does seem to come from where her Roland electronic piano is against the wall. What's amazing is that she didn't even have to be in kitchen to hear this 🙂. Only anecdotal, but makes sense that better dynamics sounds more natural.
Goes for around $15 on ebay, which is the top end of what I usually pay, but well worth it in this case.
No goop was harmed in the enjoyment of this recording...
Tonight my quest for real dynamics moved forwards as my copy of Hank Jones Arigato turned up. This is currently 3rd on the DR range database Album list - Dynamic Range Database . #1 I don't want and #2 is in the post. All for research purposes, but the Jones album is some nice Jazz and I have to say, VERY realistic. Unprompted, wife on sofa said that 'it's wierd, but sounds like they are in the room with us'. The way it's miked Jones' piano does seem to come from where her Roland electronic piano is against the wall. What's amazing is that she didn't even have to be in kitchen to hear this 🙂. Only anecdotal, but makes sense that better dynamics sounds more natural.
Goes for around $15 on ebay, which is the top end of what I usually pay, but well worth it in this case.
No goop was harmed in the enjoyment of this recording...
so you hear < 1 us, 250 udB @ 20 Hz?
20 uF, 10k Mylar coupling C with Pease DA model extra RC branches, scaled
trace is Pease' DA modeled Coupling Cap vs Spice C
cursor inset for delta dB, phase, group delay
20 uF, 10k Mylar coupling C with Pease DA model extra RC branches, scaled
trace is Pease' DA modeled Coupling Cap vs Spice C
cursor inset for delta dB, phase, group delay
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I had read that they use the battery pack to power the cameras and emitters of the videos. As well as to play in loop the Bowie tune in the in board radio.
"And now, thanks to a battery-powered camera aboard the car, you can share in the early hours of the cherry red convertible's journey.
SpaceX expected the battery to last no longer than 12 hours, as Space.com reported, and it in fact lasted just over four."
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