@soix What do you know about impedance mismatch and industrial standards? My observation is absoutely little to nothing. It’s disappointing to see advice being shared from a literally ignorant person without a proper understanding of audio. Unfounded recommendations don’t help the Audiogon community grow in knowledge.
@sls883
A further investigation / clarification to the impedance mismatch issue. Impedance mismatch causes signal reflection, which in turn has the following two impact on the signal quality.
First, mismatch loss, which is audible signal loss due to reflection, can be quantified as -10 log(1-|CR|^2) dB, where CR = Coef. of reflection = (ZL-Zc)/(ZL+Zc), ZL = load imp. And Zc=cable imp. So, using the example if MC2 coaxial is a 110 ohm into 75 ohm load, CR = 0.19 and mismatch loss = 0.16 dB. So if the signal loss due to reflection is only a fraction of a dB, why is imp. mismatch such a big deal? The answer lies in the time inaccuracy, i.e., known as jitter, caused by the signal reflection.
Second, jitter can be quantified approximately as
|CR|x (round-trip delay due to reflection) x (edge sensitivity)
If you have 5ft rca cable, which as a typical signal propagation delay of 1.5 ns/ft, and assume edge sensitivity is 1.0 for the cable w/o loss of generality, the jitter can be estimated as =.19 x (1.5x5x2) = 2.9 ns = 2900 ps, which is humongous in hi-fidelity signal chain reproduction. In general, 100 ps jitter or less is considered good and audible level of jitter is around 200-300 ps. The high-end gear typically has around 10 ps.