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<blockquote data-quote="Geoff Doane" data-source="post: 89488" data-attributes="member: 1155">Re: Maximum analog snake lengthIf you do the math, 400 feet of 30 pF/ft. cable, and an output impedance of 600Ω, gives you a 3 dB down point of 22 kHz.&nbsp; And those numbers are sort of a worst case example.&nbsp; The old Belden 8773 snake cable was 30 pF/ft.&nbsp; Most of the new stuff is less than that, unless you&#039;re using quad cable, which is likely worse.&nbsp; As JR pointed out, 600Ω is also probably a worse case for output impedances too, unless you&#039;re using the cheap stuff.&nbsp; The real corner frequency should be much higher than my example.&nbsp; As Bennett surmised, the level doesn&#039;t really enter into it, unless you get slew limiting distortion because of that extra capacitance.&nbsp; I&#039;m skeptical about concerns about level loss too.&nbsp; The previously mentioned 8773 has a DC resistance of 50 Ω/km.&nbsp; So a round trip on Jason&#039;s 328m trunk is only about 30Ω, which isn&#039;t going to make much more than a fraction of a dB difference once it&#039;s terminated in 1200Ω or so.GTD</blockquote>

[QUOTE="Geoff Doane, post: 89488, member: 1155"] Re: Maximum analog snake length If you do the math, 400 feet of 30 pF/ft. cable, and an output impedance of 600Ω, gives you a 3 dB down point of 22 kHz. And those numbers are sort of a worst case example. The old Belden 8773 snake cable was 30 pF/ft. Most of the new stuff is less than that, unless you're using quad cable, which is likely worse. As JR pointed out, 600Ω is also probably a worse case for output impedances too, unless you're using the cheap stuff. The real corner frequency should be much higher than my example. As Bennett surmised, the level doesn't really enter into it, unless you get slew limiting distortion because of that extra capacitance. I'm skeptical about concerns about level loss too. The previously mentioned 8773 has a DC resistance of 50 Ω/km. So a round trip on Jason's 328m trunk is only about 30Ω, which isn't going to make much more than a fraction of a dB difference once it's terminated in 1200Ω or so. GTD [/QUOTE]

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