Around 100ohm, typical. You can get along with 75ohm matching, is not going to be very bad. The video connectors (looking like RCAs and usually mating with RCA sockets) are 75 ohm. For audio, you may get along very well with the RCA socket discontinuity.
Really?, news to me. BTW virtually everything on the web about this is wrong. The best signal source we had for years was current out (total mis-termination at the source) but had to be carefully terminated at the load. This fact is overlooked by just about everyone. The connector has almost no effect on the termination impedance at these frequencies, nonsense around this is also everywhere.
No this is for maximum power transfer. A perfectly terminated load is sufficient for there to be no reflections or standing waves.
Or perfectly "terminated" source (series resistor) and open load end (maximum impedance). In reality, cable imperfections and added capacitive load at the end show some small "teeth" at the response, time corresponding to twice travel through the cable.
Pavel, yes I know. We are blessed to have such a technical resource here. Scott couldn't be a better fit for people interested in high performance audio, seriously.
But his expertise in social sciences may or may not be up to the same level, I don't know.
In any case, whatever I may be thinking or up to when I take a certain tact with someone, doesn't mean people should jump all over me without giving me a little time, a few posts, to try more of a long game and see how that fares.
It's not just Scott, when I said its so easy to misinterpret other peoples intentions in a text based forum, I meant its difficult for humans in general.
And maybe if I had a side-channel to talk to Scott offline, I could explain questions he may have about my intentions to his satisfaction. But, what satisfies one persons questions, may not satisfy other people with different questions. I can't explain intentions behind everything I say in extreme detail every post, it just isn't possible. In addition, I can't anticipate every possible way that my intentions might be misinterpreted, although someone else may feel it should be obvious to me how other people will interpret me, well, it isn't. Isn't that obvious?
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Yes, I'm including this in the matching condition. Otherwise, see the 75 ohm cable in the 50 ohm network case, that's a discontinuity.
Of course, everything is moot for audio. I'm having lots of fun with destroyers that insist in matching speaker cables impedance.
Now what are we quibbling about? Impedance mismatch with RCA connectors? Of course, RCA connectors do not match at 75 ohms, their construction (ratio of pin diameter and outside shell inner diameter) makes them about 50-60 ohms. Is this important? It could be.
Many self experts here rely less on listening experience of the majority of serious audio listeners than what they learned in school, and they can be just as wrong as they can be right.
Many self experts here rely less on listening experience of the majority of serious audio listeners than what they learned in school, and they can be just as wrong as they can be right.
I thought in post #93211 I simply stated some basic stuff without any editorializing. I'm not sure what would have been more helpful, and don't see an intent that could be misinterpreted. I could have computed the characteristic impedance of an RCA connector (it probably varies all over the place) and offered it with no comment on the misconceptions inherent in asking the question in the first place (re: audio).
I appreciate your interest/knowledge in the cognitive sciences please stop me if I make a comment ignorant of accepted results in this field.
Given this is DIYaudio and not SocialScienceonline I'm not sure why you bring this up. Scott and several others have been fighting against the tsunami of ignorance over basic things like jitter on here for over a decade. You only have to do a search to see this same scenario playing over again and again, often with the same protagonist. People would rather believe advertising copy or magazine monkeys that very basic science.
You can search for Jocko's posts on SPDIF on here. He was banned in the end.
I respect Jocko's knowledge and think there is a lot of value in his input, that goes for Thorsten L. also but the interaction has to go both ways. BTW my daughter asked why does this guy hate me (Jocko) she does not understand but I found it amusing.
Bill and Scott, should I take it that you are frustrated with still fighting the never ending fight against the tsunami? What do you guys think is the best way to deal with it? I ask, because I haven't been at it as long as you, so I don't know if you have had any success or not. Maybe you try to correct people, or if not, then ignore them? If so, are you satisfied with how its working? If not, then what do you find that does work?
I ask, because maybe I'm wasting my time trying my own way. But, you don't seem to be catching on to what my way is. Doesn't matter if you don't, if I'm wasting my time, then I'll leave it to you to handle the fight the way you think works best.
I ask, because maybe I'm wasting my time trying my own way. But, you don't seem to be catching on to what my way is. Doesn't matter if you don't, if I'm wasting my time, then I'll leave it to you to handle the fight the way you think works best.
I only had a brief scan of his posts (all a bit pear shaped domestically at the moment) and he did talk some sense (and at least bothered to put a TDR on some cables). But on a brief perusal he seemed to skip the actual problem caused by reflection induced jitter. Worth reading to see some of the wild west days of this forum 
Does your daughter understand the joke about arguing with a technical type is like wrestling a pig in mud?
Does your daughter understand the joke about arguing with a technical type is like wrestling a pig in mud?
Mark: I can't speak for Scott, but I am more in learning mode as are many others. Many 'big names' have given up on this site over the last 10 years as the signal to noise can get very low. However there are enough great things going on here that I keep coming back.
My system, although in flux is evolving in a completely different direction than I could have imagined thanks to the wise words of the collective centuries of real world experience on here. May not sound any better at the end but the journey is at least half the fun.
My system, although in flux is evolving in a completely different direction than I could have imagined thanks to the wise words of the collective centuries of real world experience on here. May not sound any better at the end but the journey is at least half the fun.
John I can always count on you, the characteristic impedance of 1/4" to 1/2" of connector has virtually nothing to do with anything. It amounts to a fraction of a pF or nH discontinuity depending on if it's above or below 75 Ohms. The same is true if you put a c-clamp on the cable and compressed a 1/2" or so. A new tweek is born, properly spaced Jorgenson Clamps (preferably made of myrtle) on your SPDIF cables.
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