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    How long can I run RCA coax at line level?

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    deepee99

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    How long can I run RCA coax at line level?

    Post by deepee99 on Sun Dec 14, 2014 11:27 pm

    How long of a run can I make of RCA coax at line (not phono) level? Reason I ask is that I lucked out with a very fine sound card on my antique Lenovo computer, have been having much fun with Spotify and Tidal here in the den with the Bedini sand amps. Giving some serious thought to hooking one of those two music sources up to the toobs in the tuner slot. It would take quite a run, mebbe 50 feet per channel. Anybody strung that length with any luck?
    Any ideas, sources, experiences, tweaks? I am sure AudioQuest could fix me up at $1,000 per millimetre. At what length does generic RCA shielded cable start to go pear-shaped?
    I will ask the guys at Blue Jeans tomorrow and report back, but would appreciate any thoughts on this topic.
    And no, sKiZo, How Long is not a Chinese person...



    sKiZo

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    Re: How long can I run RCA coax at line level?

    Post by sKiZo on Mon Dec 15, 2014 1:03 am

    Wong Long Dong?

    Length of unbalanced lines depends on what all you've got for interference. If you're running just a set or two, there shouldn't be much cross talk. A bundle of signal cables, and the maximum length drops fast. That's why balanced XLRs are the way to go in pro and setups.

    You'll see 15 foot quoted a lot, but I've got a couple pairs of 25 footers between my TV room and the stereo, and those sound fine. Then again, I'm not going for audiophile grade there.

    And, of course, the quality of the cables comes into play as well. But you knew that ...

    That said, at 50 foot, you might be better off going wireless?

    sailor

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    Re: How long can I run RCA coax at line level?

    Post by sailor on Tue Dec 16, 2014 12:23 pm

    How long your cables can be is dependent on the capacitance of the cables and the amperage and impedance of your output [source]. Your preamp is not in the equation as everything bad has already happened before it reaches it. What will happen is your highs will be rolled off. How much is directly related to the above parameters. As far as cables I make my own. Far cheaper and better than you can buy. Twisted triple 22 gauge stranded and silvered wire with Eichmann bullet RCA ends. Very low impedance. Third wire attaches only to source end, cut clean at the other end and is used to remove outside noise.
    The problem as I see it is the sound card. It would have low impedance but it would not have the amperage necessary for that long of a run.

    deepee99

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    Location : Wallace, Idaho

    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Fri Jan 02, 2015 1:04 pm

    Thanks for the advice, gents. Sounds like wi-fi could be a better way...

    sKiZo

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    Re: How long can I run RCA coax at line level?

    Post by sKiZo on Fri Jan 02, 2015 1:17 pm

    Yeah ... signal's already traveled light years to get to your planet ... what's a few more feet? alien

    PS ... what's Spotify and Tidal run for SQ anyway? Low enough, and you might not even notice the difference, especially if you're just using it for back round music ...

    Does bring to mind another question ... wireless speakers. Can you get "matched" pairs that all use the same frequency? Be nice to be able to just scatter pairs as needed with only one transmitter.

    corndog71

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    Re: How long can I run RCA coax at line level?

    Post by corndog71 on Fri Jan 02, 2015 1:23 pm

    sKiZo wrote:Yeah ... signal's already traveled light years to get to your planet ... what's a few more feet? alien

    PS ... what's Spotify and Tidal run for SQ anyway? Low enough, and you might not even notice the difference, especially if you're just using it for back round music ...

    Does bring to mind another question ... wireless speakers. Can you get "matched" pairs that all use the same frequency? Be nice to be able to just scatter pairs as needed with only one transmitter.

    Sonos are ok for "wireless" speakers. Still gotta plug them into the wall. Suspect

    deepee99

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    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Fri Jan 02, 2015 1:39 pm

    Spotify premium player is 320k, still in beta for linux so I've quit using it; too many crashes.
    Tidal premium is 1411 kbps, and that's streaming through the browser, which ain't bad, but at twice the price as Spotify premium ($10 vs. $20/mo).
    Either one kick's Apple's butt.
    Spotify has a more comprehensive catalogue but Tidal is catching rapidly up and supports FLAC, whatever that is . . .
    Having used both in my sand amps (Bedinis to A-35s), I can hear a definite improvement in Tidal's 1411 SQ. It self-buffers (izzat a term?) so it takes a few seconds to load an album or selected tune but once you're there, you're there. If Spotify gets their linux player out of beta I will give them one more shot.
    The spotify player would probably be better if your internet connexion is slow.
    To move this whole shagaree into the living room and the M-125s, I'm thinking just a high-grade ethernet cable from the modem to a dedicated computer with a half-arsed decent sound card.
    Am in no rush; this technology is in its infancy.

    Zimmer64

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    Re: How long can I run RCA coax at line level?

    Post by Zimmer64 on Fri Jan 02, 2015 3:25 pm

    Hi,

    I have made good experience with a line driver of Abacus http://www.abacus-electronics.de/45-1-Line+Driver.html (I am not related or affiliated etc.).

    Michael

    deepee99

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    Join date : 2012-05-23
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    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Fri Jan 02, 2015 3:39 pm

    Zimmer64 wrote:Hi,

    I have made good experience with a line driver of Abacus http://www.abacus-electronics.de/45-1-Line+Driver.html (I am not related or affiliated etc.).

    Michael

    Michael, is it MS or Apple specific, or can it hack to linux?

    audiobill

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    Location : Philadelphia

    Re: How long can I run RCA coax at line level?

    Post by audiobill on Fri Jan 02, 2015 4:35 pm

    Get the Airserver app on your computer, and an Airport express connected to your tube amp setup.

    Then just connect wirelessly to your tubes.

    Or, connect an ethernet cable from your computer to the Airport Express.

    $99 for the Airport Express.

    deepee99

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    Join date : 2012-05-23
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    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Fri Jan 02, 2015 4:48 pm

    audiobill wrote:Get the Airserver app on your computer, and an Airport express connected to your tube amp setup.

    Then just connect wirelessly to your tubes.

    Or, connect an ethernet cable from your computer to the Airport Express.

    $99 for the Airport Express.

    Bill, will it handle 1441? Now ya got me drooling . . .

    audiobill

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    Re: How long can I run RCA coax at line level?

    Post by audiobill on Fri Jan 02, 2015 5:02 pm

    Yes, I do this every day.

    PM me your phone number if you want to talk this through.

    Bill

    deepee99

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    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Fri Jan 02, 2015 5:08 pm

    audiobill wrote:Yes, I do this every day.

    PM me your phone number if you want to talk this through.

    Bill

    Bill, will do. Many, many tnx.

    mantha3

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    Re: How long can I run RCA coax at line level?

    Post by mantha3 on Sat Jan 03, 2015 12:53 pm

    Run this to a tube buffer and then do a long run from the tube buffer to the system

    sKiZo

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    Location : Michigan USA

    Re: How long can I run RCA coax at line level?

    Post by sKiZo on Sat Jan 03, 2015 1:35 pm

    It's not signal LOSS that's the issue with long RCA runs, it's signal GAIN, in the form of external induced noise, especially stray RF ...

    Here's another option. Two baluns that convert RCA audio for long line transmission on CAT5 cable. Supposed to be good up to 300 feet with no ground loop issues or hum, and CAT5 is more or less immune to external noise ...

    http://www.parts-express.com/composite-video-and-stereo-audio-to-rj45-balun-pair--183-335

    At $40, not that expensive an experiment either ...

    * They've also got a coaxial (S/PDIF) version that allows you up to 1000 feet.


    Zimmer64

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    Re: How long can I run RCA coax at line level?

    Post by Zimmer64 on Sat Jan 03, 2015 3:16 pm

    deepee99 wrote:
    Zimmer64 wrote:Hi,

    I have made good experience with a line driver of Abacus http://www.abacus-electronics.de/45-1-Line+Driver.html (I am not related or affiliated etc.).

    Michael

    Michael, is it MS or Apple specific, or can it hack to linux?

    Not OS specific. It is an audio component.

    Michael

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Just to put a coda on things . . .

    Post by deepee99 on Sat Jan 17, 2015 9:54 am

    . . .
    Audio Bill came to the rescue here, and we've now got streaming Tidal throughout the house that is screaming along at red-book or better resolution. I can plonk myself anywhere in the crib and listen to pretty much what I want.
    It took two of those dollar-sized Apple AirPort Express thingies, at $100 a pop; one for the sand amps and one for the toobs. And about 16 hours of Bill's time over the telephone to get everything synchronised with an iPad, the Linux box and my coal-powered 4s iPhone. I cannot thank Audio Bill enough for his time and patience with this technophobe.
    Everything works, and the DACs inside these little Mac AirPort thingies sound darned good through either system. I especially noticed an improvement in the Bedini s/s amps. And no extra holes in the floor and long questionable runs of co-ax or ethernet cables.
    At any rate, a shout-out to Bill for all his kind and gracious help and yes, Virginia, there's a $100 way to get decent sound off the internet. It ain't quite vinyl but it's close.


    audiobill

    Posts : 271
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    Re: How long can I run RCA coax at line level?

    Post by audiobill on Sat Jan 17, 2015 10:21 am

    David, you're too kind!

    I also like having 25 million tunes at my disposal, for $20 per month.

    That's about the price of one CD or download.

    Tidal was the big hit at CES this year, according to Stereophile.

    Good Listening!

    Bill

    deepee99

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    Join date : 2012-05-23
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    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Sat Jan 17, 2015 10:29 am

    audiobill wrote:David, you're too kind!

    I also like having 25 million tunes at my disposal, for $20 per month.

    That's about the price of one CD or download.

    Tidal was the big hit at CES this year, according to Stereophile.

    Good Listening!

    Bill
    Bill, I'm not kind enough. Cannot thank you sufficiently for the time you spent on this technophobe.
    Streaming Fairport Convention right now. Always had a thing for Sandy Denny... Her cover of Dylan's Percy's Song will warm the hardest of hearts.
    -d-



    bluerondo

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    Re: How long can I run RCA coax at line level?

    Post by bluerondo on Sat Jan 17, 2015 12:34 pm

    Those airport expresses sure are convenient way to stream from iPhone. They also act as a wifi range expander and USB printer port. I put one in a small box with amp, speakers and power supply. The range is way better than a Bluetooth speaker.

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: How long can I run RCA coax at line level?

    Post by deepee99 on Sat Jan 17, 2015 12:49 pm

    bluerondo wrote:Those airport expresses sure are convenient way to stream from iPhone. They also act as a wifi range expander and USB printer  port. I put one in a small box with amp, speakers and power supply. The range is way better than a Bluetooth speaker.

    Well as I mentioned it took a bit of heavy lifting on Audio Bill's part to get these Airport gizmos running, but once you're there, you're there.
    I've never had much luck with Bluetooth and wouldn't dream of pushing 1441 over it.
    The way Audio Bill set me up, all the iPhone/iPad do is control things; the airporters act as their own DACs so you're not crimped with the phone's audio capabilities.
    As mentioned previously, I have a noticeable improvement in the s/s amps, and a subtle improvement on the toobs. Not bad for $20 a month and $200 up front. A guy could do a lot worse for a lot more money.
    Cheerio
    -d-

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