What makes an interconnect sound like it does?

Impedance matching ? The impedances are supposed to be mismatched (low output impedance, high input impedance). An RCA interconnect should transfer voltage, not current.

However if the source has an unusually high output impedance, and the destination has a rather low input impedance then this will cause distortion in the signal ... perhaps this is what loontoon was referring to ?

My guess (based on some personal experience) is that quality of connection and overall capacitance are the two keys. For connection quality make sure everything is really really clean, and free from oxidation. For low capacitance I think you'd have to avoid the shielded coax type interconnects, use as much air as dielectric as possible, and PTFE where a dielectric must be used.

I think silver is possibly the best conductor because even surface oxide is conductive, gold is a lousy conductor (relatively) but prevents oxide formation on terminations.

That said I think capacitance is much more importance than resistance so copper / silver may be a wash.

I always solder because I don't have crimping tools.

Loontoon,

As counter-intuituive as is may sound, I don't believe you *really* want to impedance match your components. Modern solid-state devices transfer voltage between products, not power. Optimum power transfer requires impedance matching. Optimum voltage transfer does not.

Today’s products have high input impedances and low output impedances. These are compatible with each other. Low impedance output stages drive high impedance input stages. This way, there is no loading, or signal loss, between stages. No longer concerned about the transfer of power, today’s low output/high input impedances allow the almost lossless transfer of signal voltages.

For example, the positive and negative outputs of the driving unit have an output impedance labeled ROUT. Each input has an impedance labeled RIN. Typically these are around 100 Ω for ROUT and 20k Ω for RIN. Georg Ohm taught us that 100 Ω driving 20k Ω (looking only at one side for simplicity) creates a voltage divider, but a very small one (-0.04 dB). This illustrates the above point about achieving almost perfect voltage transfer, if impedance matching is not done.

If it is done, you lose half your signal. Here’s how: impedance matching these units involves adding 100 Ω resistors (equal to ROUT) to each input (paralleling RIN). The new input impedance now becomes essentially the same as the output impedance (100 Ω in parallel with 20 kΩ equals 99.5 Ω), therefore matching. Applying Ohm’s law to this new circuit tells us that 100 Ω driving 100 Ω creates a voltage divider of ½. That is, ½ of our signal drops across ROUT and ½ drops across RIN, for a voltage loss of 6 dB. We lose half our signal in heat across ROUT. Not a terribly desirable thing to do.

Of course, I could be wrong. What the hell do I know?

And don't forget that an IC that is PERFECT in one place in your system may not work well at all in another. Just thought I'd throw that in to help ease your choices in wire.

Enjoy,
Bob

Don't forget shielding types and configurations, as well as vibration management in the overall cable structure. These are very important considerations in both the sonic performance, and the noise floor performance.

The termination, and for you flat earthers that believe that only gas tight crimp will do, I got news for ya, there's a darn good reason that the government spec's solder for it's termination joints. Repeatability and reliability. Only in theory is a crimped joint better.

The US spec's gold and silver clading or plating, and often times gold connectors, and SILVER Solder. Most high end critical signal or data transmission cables are high quality copper with silver plating.

So: What causes the sound differences is mostly termination and last: it's the length and the capacitance, reactance, impedance, resistanct, inductance that either adds or subtracts from the signal that colors the sound.

Which is why many poeple who don't understand what the cable is doing chase and spend many $$$ finding the exact coloration that perks up their system. Match you impedances on the components upfront, buy quality copper and silver solder to locking connectors and the interconnect game comes to an end. Since your springing for maybe a couple of bucks go whole hog and silver plate the cable and hey use teflon foamed insulation, twist, braid, etc, what ever floats you boat via the snake oil in whatever add you've taken a fancy to, add inexpensive locking WBT type RCA's from PE and your out maybe $15 and an hour of time.

But if your components impedances are mismatched I suggest fixing the real issue prior to chasing down big bucks in interconnects. You did impedance match you components, right!!! A nasty little secret that very few salons will tell you about. Even in the same manufacturer and family the impedances may not be matched. Ask the dealer you buy from, and if he can't tell you, get away fast.

loontoon,

Everything. Quantity, type, and size of conductors; conductor materials; how the conductors are braided, twisted, etc.; insulation material; outer jacket; connector type, material, and design; method of termination and materials used; type and amount of heat shrink. There are many others. Fine tuning often takes years of experimentation.

"What makes speakers sound different?"

Glad you asked. Not because I think this is an appropriate place to discuss this question (that's for another thread), but becuase your question facilitates a good analogy.

I can make some generalizations about the sound of a speaker that is based upon an electro-static design vs. a speaker based upon dynamic electro-mechanical design. A sealed "acousic suspension" design vs. a ported "bass reflex" design. 1st-order crossovers vs. 4th-order corssovers. Etc...

Now, are these generalizations accurate all of the time? Nope - that's why they are called "generalizations." However, it does give you things to consider. I think it would be interesting to discuss generalizations about cable design.

Just some thoughts, the looser the cable is wounded together, the less mechanical vibration will "pollute" the singal path.

Low mass terminations will help in that department as well as reducing emi/rfi.

And, slightly less resistance/higher gauge on the ground wire does provide for a smoother more spacious sound.

Conductors, as long as they are atleast 99.95% pure is good. As for silver, soft annealed seem to be it thing for the moment. Palladium is similar and doesn't corrode but costs a lot.

What makes speakers sound different?

With interconnects, it sounds like you have the idea. What are they made of? Geometery, insulation, termination, the connector's themselves, cryogenically treated, and the quantity/quality of everything that was used to make them all change the sound. There is no universal secret formula to making "good" sounding interconnects- it typically involves a lot of trial an error, a great understanding of science and math and the ability to replicate your creations the exact same way time and time again.