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Mar 30, 2009, 01:48 PM
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Russian Heroine dreams


Dreamed Russian Heroine became a rich banker & formed her own olympic swimming program. She hired some coaches & athletes. She was much older, sitting in a chair next to the pool, & her athlete lover swam over.

We figured the program was just a way of providing a constant supply of men to make love with. She still recognised us but was much more interested in her athlete.

In another dream, we joined a startup full of Russian programmers & she came in, yelled & screamed about stalking her. It was on some university in a classroom.

Vacuum tubes forever

Hopefully U all saw this Gizmodo revelation about vacuum tubes.

Electrons on Parade pt 1 - RCA (9 min 31 sec)


U can't blog about sonar without bringing up vacuum tubes. The answer is yes, BYU used vacuum tubes in its recording studio in 1997. More specifically, a pair of tube leveling amplifiers. Vacuum tubes still are the only way to get certain sounds just like a Steinway is the only way to get certain sounds.

So U want to simulate vacuum tubes in software, eh.

The truth about digital audio

Sampled audio at 48khz can't reproduce a 440Hz sound. It can alternate between 440.366972Hz & 436.363636Hz to try to fake it, but it can't do the 440Hz your great great grandparents heard on their LP's. To make discretely sampled audio do every frequency that analog did, it would have to sample millions of Hz at 24 bits. It literally amounts to digitizing the molecular structure of the complete physical tape.

Wouldn't be surprised if no-one in the current generation ever heard true A440.


Kinetic energy busters

The kinetic energy credit card had some more problems. It took -2v to rewind the first mass, so the second mass needed 3v. The 3v mass would finish its movement before the -2v mass rewound. Since each mass movement took less time to complete than the previous one, a new mass would be required for every movement. There was no way to defer kinetic energy repayment.
Last edited by Jack Crossfire; Mar 30, 2009 at 06:05 PM.
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Mar 31, 2009, 05:23 PM
High speed bug smasher
heli_addict's Avatar

Digital Audio cannot produce 440Hz?


I fail to understand how digital audio sampled at 48KHz cannot produce 440 Hz. With over 100 samples per wavelength, I am convinced it can very accurately reproduce 440 Hz. Please explain your claim or point to a reputable publication that presents this argument.

If you are referring to the fact that 48000 is not an even multiple of 440, I believe that to be quite irrelevent, since it does not matter precisely where the peak sample falls. The D/A conversion will effectively handle the potential 4Hz difference there quite handily.

Have you done an A/B comparison between an analog 440 Hz source and a digitally reproduced or generated 440Hz source? Can the ear actually perceive the difference? If not, what does it really matter?
Apr 02, 2009, 08:11 AM
Old retired Electronics Fart
Charles B's Avatar

The second part of the Vacuum tubes


I like the video on the Vacuum tubes Part #1 here is the second part of the
Video.

Electrons on Parade Pt 2 - RCA (9 min 16 sec)


CharlesB

PS
I read all most all your post . Keep up the good work !


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