If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Rate Thread | Display Modes |
#9
|
|||
|
|||
Blue, white, and HDMI cables for a 23-inch diagonal monitor
Jean Fredette wrote:
I have no idea what the third choice switches to though. SPDIF: That's either TOSLink (glowing red LED color, leaks through rubber capped square connector on back of PC), or it can be delivered by legacy copper coax connection (RCA/Cinch connector, same style connector which peppers the back of large screen TV sets). The SPDIF connector isn't keyed, so it can "go in the wrong holes", and with RCA/Cinch you do have to be careful. Audio doesn't have the same attention to detail as computer connectors. At least a few things on computers "won't fit" to help prevent you from blowing stuff up. You can see rather poor examples of both here. (The RCA/Cinch should be showing more metal reflections in the picture.) https://www.dx.com/p/spdif-toslink-t...7#.XJK1YaUwDQx The TOSLink is a fiber optic connection that uses plastic "dental" fiber, the same kind of fiber that conducts light for dental work. The connector is squarish on its perimeter. On the "out" connector, you would see red LED light "leaking" from under the rubber cover on the port. You peel back the rubber cover, before inserting the cable. The RCA/Cinch is for the copper equivalent of the signal. https://en.wikipedia.org/wiki/RCA_connector The signal in that case, is carried on coaxial cable, with RCA/Cinch on either end. The signal might have a characteristic impedance of 50 ohms. The RCA/Cinch is a lousy choice for maintaining a 50 ohm environment (it's not an RF connector). When you look at cable TV connectors, F-series maybe, those are 75 ohms and are going to be closer to being the proper impedance for their application. RCA/Cinch are used for: Audio speakers Line In audio Composite video (red/yellow/white on TV back) YPbPr video ? SPDIF The Speaker Out on a high power stereo, would likely have sufficient amplitude to destroy the SPDIF-In on your AV receiver, if connecting the cable to the wrong holes. But in any case, both TOSLink/RCA SPDIF standards carry a 6Mbit/sec stream, sufficient for two channels of high definition audio. An alternate format, is to support four channels using "fewer bits", which would not particularly be an audiophile choice. I keep seeing references to that mode, but nothing seems to use it. When computers first got "digital audio", it was just that RCA connector. It was only later that TOSLink optical output was offered, and at first, there was an adapter card you put in a PC slot with the simple driving components (LED and switching transistor). Later, TOSLink got put in the I/O plate area, and PCs could have both TOSLink and SPDIF at the same time. When you have both, you can drive two home theater receivers at the same time, since SPDIF is unidirectional and the PC only "sends" to each AV receiver. The TOSLink and RCA, are copies of the same signal. PCs have also had SPDIF-in, but that was only via the adapter card that sits in a slot. The reason the industry tried to "hide" that one, was DRM and "making perfect copies" of audio content. They didn't want to encourage people to use computers to record digital audio. But the *******s did have a way to "get even", as some 24 bit audio sent that way, had the 8 least significant bits "set to zero" to "ruin" the resolution, making perfect copies impossible. So while the user might have a big **** eating grin on their face "recording 24 bit audio", they were in fact only getting 16 bit copies. You could always examine a recording with your hex editor, and figure out you were "ripped off". Paul |
Thread Tools | |
Display Modes | Rate This Thread |
|
|