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THX Caught With Pants Down Over Lexicon Blu-ray Player
SchlimpyChicken writes "Lexicon and THX apparently attempted to pull a fast one on the consumer electronics industry, but got caught this week when a couple websites exposed the fact that the high-end electronics company put a nearly-unmodified $500 Oppo Blu-ray player into a new Lexicon chassis and was selling it for $3500. AV Rant broke the story first on its home theater podcast with some pics of the two players' internals. Audioholics.com then posted a full suite of pics and tested the players with an Audio Precision analyzer. Both showed identical analogue audio performance and both failed a couple of basic THX specifications. Audioholics also posted commentary from THX on the matter and noted that both companies appear to be in a mad scramble to hide the fact that the player was ever deemed THX certified."
I tell you, audiophiles have NO IDEA OF SCALE.
I am working with HF stuff. I run on cables that cost as much as that one, but in bulk supply from industry vendors (Huber+Suhner, for example). Because they are linear to 18 Ghz.
I also did an experiment where i had to synchronize two signals to some picoseconds, and that is damn hard. Damn hard in the sense of "a day of quality time with a network analyser and a few delaylines".
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Speaking again on HDMI: Yeah, it matters for it, as its fucking running at several hundred times the datarate than an audio connection.
HDMI is specified to transport up to 10Gbits/s, multiplexed on only 19 conductors.
Compare again with audio datarates...
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
sorry, but the maximum speed of i2c is 3.4 mbps. you will need about 9m difference in length to have 10% of phase difference between your clock and your data, using the maximum speed (the usual one is 100-400 kbps). I agree that cat5(e) was not designed for i2c signals, but is more than enough for this application.
At 20kHz two chunks of aluminum makes for a pretty nice cable. With 50GHz coax you need tiny precision machined connectors (2.4mm), and a very narrow cable with a low permittivity dielectric. Such a cable costs about $2,000.
The reason for the precision, size, and expense at those frequencies (as you know but others probably don't) is that if you have a large cable, there are multiple different wave equation solutions (modes) which allow power of a particular frequency to travel down a cable, and they will propagate at different speeds in the cable (and different attenuations), so what you get out of the cable is a distorted version of the input. So you must make the cable with size on the order of the smallest wavelength you intend to transmit. And it has to be precisely made because imperfections, scratches, and so on need to be even smaller or they will cause an impedance shift which reflects some signal back at the source.
At 50Ghz a wavelength is 6mm. At 20kHz it is 15km. This is why it is easy to make very nice audio cables, and hard to make nice HF cables.
Well, it was Grace Hopper and she's the mother of COBOL, not FORTRAN. She used to give out "nanoseconds" at her lectures. They were 11.9 inch lengths of wire, which represents how far electricity can go in a nanosecond. A friend of mine still has one of these "nanoseconds" he got from her.