Where does clipping take place (for sherlocks holmses:))?

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mshilarious said:
That depends on the characteristic impedance of the cable, you just have to check if it's 75 ohm . . . and also its length. The rule of thumb for a cable to act as a transmission line is 1/10 wavelength, which for S/PDIF (running about 3mHz) is 10m. Really, S/PDIF is rather tolerant of peccadillos . . .

AES, on the other hand is designed for longer cable runs, if so you should seek out 110 ohm cable.
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Well I've tried it with short RCA cables and it didn't work for me,plus everything I read has said to get the proper cable.A SPDIF cable isn't very costly,why would anyone recommend using an RCA cable if there could be potential problems?:confused:Which cable would you recommend?
 
dintymoore said:
I want to know where all the stuff that's clipped ends up?
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In a scrapbook of course.

scrapbook.jpg
 
acidrock said:
Well I've tried it with short RCA cables and it didn't work for me,plus everything I read has said to get the proper cable.A SPDIF cable isn't very costly,why would anyone recommend using an RCA cable if there could be potential problems?:confused:Which cable would you recommend?
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If I were going out to buy a cable, I would buy 75 ohm cable. But if I had an RCA cable laying around of unknown impedance, I would probably try that first. If I got dropouts, I would not use it. I have not experienced problems with garden-variety RCA cables (which could be 75 ohm, although I think most audio ones aren't). The only that matters should be its impedance, and more so as length grows. It is probably worse if the connecting gear isn't properly terminated, which should never happen but who knows? I suppose it's also possible that poor shielding could cause enough signal degradation to drop bits, as S/PDIF is unbalanced . . .

I think that the video composite (yellow) RCA cable is supposed to be 75 ohm, so I'd grab one of those out of a bucket of random cables if I had the choice . . .

Some good discussion here from a company that seems to understand physics and avoids snake oil:

http://www.audioholics.com/buying-guides/how-to-shop/cable-budget-guidelines
 
dintymoore said:
I want to know where all the stuff that's clipped ends up? I've been doing it since the 60's - that's a lot of stuff. Where is it now? Is there a big pile somewhere? Who legally owns it? Can you eat it?
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It's sitting on the barbershop floor, in the corner. After clipping, he uses a hair dryer as a pseudo leaf blower to corral it into the corner. The pile grows large during the day depending upon the amount of clipping and the number of clippees. At the end of the day, a hunchback comes and sweeps it up and sells it as pillow stuffing.

You can eat it if you like, lots of fibre, not much taste. Metamucil is a better bet for regularity...
 
Props to LDS and mshilarious for solving the problem and giving it its real name.

Personally I find it very useful when some of the people who know far more than I do about stuff (that's most of you..) share their knowledge, in or out of context, so thanks too to mshilarious for the impedance stuff.:D
 
mshilarious said:
If I were going out to buy a cable, I would buy 75 ohm cable. But if I had an RCA cable laying around of unknown impedance, I would probably try that first. If I got dropouts, I would not use it. I have not experienced problems with garden-variety RCA cables (which could be 75 ohm, although I think most audio ones aren't). The only that matters should be its impedance, and more so as length grows. It is probably worse if the connecting gear isn't properly terminated, which should never happen but who knows? I suppose it's also possible that poor shielding could cause enough signal degradation to drop bits, as S/PDIF is unbalanced . . .

I think that the video composite (yellow) RCA cable is supposed to be 75 ohm, so I'd grab one of those out of a bucket of random cables if I had the choice . . .

Some good discussion here from a company that seems to understand physics and avoids snake oil:

http://www.audioholics.com/buying-guides/how-to-shop/cable-budget-guidelines
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I would recommend just getting a SPDIF and not taking any chances.I'm more interested in making music than proving you can use an RCA.:rolleyes:
 
is anyone else resisting the urge to post a picture of the borg with the caption "resistance is futile" ?
 
acidrock said:
I would recommend just getting a SPDIF and not taking any chances.I'm more interested in making music than proving you can use an RCA.:rolleyes:
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OK, a "S/PDIF cable" or "digital cable" IS is an RCA cable with 75 ohm impedance. So that's what I would use, regardless of the name on the box. I would have only one question, is it 75 ohm?

Edit: and here is what tweakheadz says on the matter:

tweakheadz said:
Q) Can I use an RCA cable as a digital s/pdif coax cable.

A) If it is well shielded, it might work. With a cheap cable, the data may get garbled and your computer will send up alert boxes saying "unknown format", or "wrong sample rate", or something unintelligible. Ideally these digital cables have 75ohm cable in them (like your TV cable). You could make one out of extra TV cable you have laying around.
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http://tweakheadz.com/all_about_cables.htm
 
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LDS said:
I'm glad that your focus is on assisting the OP rather than self-aggrandizement. Oh, wait. Strike that. Reverse it.

So, plugging a line level output into a mic input isn't an impedance mismatch? I believe you're arguing semantics more than anything.

Dude, try driving a 4 ohm load with a 16 ohm tap off of an amp's output transformer. By your definition, that's not an impedance mismatch, but it time it will definitely cause the xfrmr to fail.
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bouldersoundguy said:
No, it's not an impedance mismatch if it's a balanced low impedance line out into a balanced low impedance mic input. It's a voltage (level) mismatch.
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ditto ^^^^^^

and I doubt very much that you'll fry a transformer by running a 4 ohm speaker from the 16ohm tap. Yopu'll have less output than you would from the 4 ohm tap but that's what the taps are for ..... maximizing output, not to protect the amp from damage.
 
mshilarious said:
OK, a "S/PDIF cable" or "digital cable" IS is an RCA cable with 75 ohm impedance. So that's what I would use, regardless of the name on the box. I would have only one question, is it 75 ohm?

Edit: and here is what tweakheadz says on the matter:



http://tweakheadz.com/all_about_cables.htm
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I always wondered why they would make a cable the exact same as another format.:confused:
I'm going to go backwards and put digital cables in place of my RCAs.:D
 
acidrock said:
I always wondered why they would make a cable the exact same as another format.:confused:
I'm going to go backwards and put digital cables in place of my RCAs.:D
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That would work fine, audio is not particular until you get to kilometer length.

I worry a little bit about certain vendors who shall remain nameless--there is no law that says a cable marketed as "digital" has to be the correct impedance for the intended use. Even so, I suspect the vast majority of them are. Still, that's why I'd want to see the words "75 ohm" on the package.
 
drstawl said:
The Gold-Plated Hosa set I got for $5 DID specify the impedance and have been in use for a long, long time.
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Very good, it shouldn't really require spending a lot of money with these things being mass-market due to the video world . . .
 
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