Isn't 94% shielding is enough to keep most RFI away? By the way, what will RFI affect, noise floor?
My speakers are not that high end, Athena B1s, but I will get Axioms soon though.
What I'm concerned the most about is won't long cable run degrade the sound quality (aside from external interferences)?
Hi gevorg,
Due to the way I designed my listening room 18 years ago, I run 35' ICs from my preamp to my active crossovers (they run through conduit in the slab; unfortunately, due to WAF my speakers are up one end of a 27' room and my sources are up the other).
There is no intrinsic problem with long ICs if you have a "normal" relationship of source and destination (destination Zin (input impedance) is > 10x source Zout (output impedance)). If you "disobey" this rule-of-thumb then you might be getting treble rolloff due to a too-high IC capacitance with such a long run.
I suggest 94% shielding is absolutely fine - though this does depend on where you live. If you happen to live next to an aircraft control tower or an FM station you might have a problem ... however, this would be pretty obvious!
At one stage, these 35' ICs of mine were unshielded ... now they are shielded but I don't notice much in the way of "sonic improvement" due to the shield. Then again, maybe I've got tin ears!
What RFI can do to your sound is give the high frequencies a metallic edge (like a typical bad ss amplifier!) ... I myself have never been conscious of this because I think in Oz, we typically don't suffer the high RFI levels which the US does.
If you are really concerned about RF, I suggest you contact Al Sekela who posts on AA - he's a mine of information about RFI.
Regards,
Andy
