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Turn up your volume 1-2 clicks. I swear, the JRob cables almost seem to pad down volume compared to my old cables. JRobs get better the louder you go!

$5 was so I could print a postage label on PP, but that didn't work because of gift PP.

The cable itself was free.

Some of the naive objectivists out there claim that cable doesn't break in (because they can't explain it via simple first-order physical models). They say the listener breaks in...as if that is easy to explain.

I will grant that sometimes a period of adjustment is involved when a new gestalt is presented and I find that it takes a while to fully evaluate changes. Generally, I am wary of newfound excitement and some flavors of enhanced detail because I know a week later I will be yanking that thing--cap, wire, tube, whatever-- out of the system.

Often, I just don't feel right, not involved or not relaxed when I am not actively trying to judge the sound. I notice how I feel uneasy, not what I am hearing, sometimes, just listening and doing what I do. YANK!!!

A good change is one that I don't hardly notice unless I am working at noticing. It makes the system more psychologically transparent, one might say.

But everybody has their own quirks and I happen to like mine best.

And I get better the louder I get!

@brumbo--The RG-223/u under discussion uses silver plated solid copper center. Gore doesn't say what is in the Phaseflex. Some microwave cable is copper plated aluminum, e.g. some of the Times Microwave LMR wires.

Solid copper center conductor is relatively rare in USA spec RF cables. I found more German cables with solid copper conductors for some reason, some cross listed to US spec cable with copperweld centers. I can understand plated steel for tensile strength and economy for RF applications. They weren't worried about how these things sound in high-end audio systems!

What did you use for RCAs?Roscoe

I found a set of four in my parts stash and do not remember where I got them, maybe ebay
look like brass
I covered them with heatshrink so I cannot take a picture










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As luck would have it, found a thread where a guy measured the capacitance of various cables:

http://audiokarma.org/forums/index.php? ... es.697457/

Seems the RG-223 is in line with average values...but note that some of the cables are in fact made out of RF cable, e.g. the Monoprice $3 jobs are RG-59. $3...now that is my kinda price tag. Yeah, buddy. High end, Yo!

I measured my two foot length and got 101pf.
I am using an $200 ebay LCR
the two foot shot gun cable measured 90pf
a ten foot cheapie measured 400pf

$200 LCR meter? Wow, for $200 I'd want a meter and a nice suit!

With very low impedance line drivers, might not have to worry so much about C, but with plate follower tube output and such, this can get ugly quick!

With standard RG cables, the C is controlled and specified. With crazed "audiophile" creations....who knows?

I submit that there are a lot of mysterious, or at least non-understood, things going on with audio cables or, rather, cables in audio service, but you can't get around basic qualities such as capacitance.

I chopped you off a 60' length and will pop that in the mail when I can.

As J-Rob pointed out: Experience tells me that one must drive these things with a robust source. It's not enough to have a low source output impedance, the source must also be running at a substantial enough current such that the current needed to drive the load impedance [amplifier input impedance, cable impedance, stray impedances] is insignificant compared to the standing current in the source.

I suspect that interconnects have a greater effect on the sound of a system with a weak source. A lot of guys in the club have passive line stages, that will exacerbate the situation, now the source has to drive the amp, possibly highly non-linear cable loads and a ~10k attenuator.

I was surprised my phono stage did as well as it did at the show with David M's passive line stage. The output is just a 6SN7 follower @ 7mA, but it is DC coupled, cathode and 47Ω series resistor to the load. Had I designed for a passive attenuator, a much more robust tube would have been used there, probably 6BX7. Maybe even a 6AS7!

If you are worried about output impedance check this spec out. Note that even with open loop conditions (which you would never use) the output impedance is only 13 ohms at 10 KHz. And it goes down from there. The output current is 26 ma. Generally you would work with a resistor on the output of about 200 ohms for stability which is still very low output impedance.

Tom

The old rule of thumb of drive impedance 5-10X lower than load is a good one, but you have to look at the specific case to understand what the tradeoffs are.

e.g. When driving reactive loads, it may help to have some series impedance to reduce/eliminate ringing.

I have seen this with silver wire amorphous core 10k input transformers. Those suckers wanted to take off and fly. 100 ohms in series and they calmed right down.

Transducers, transformers, etc. are a more complex situation than driving a resistor.

I don't know if this is a problem with the autoformers in question. Probably not. I think if the drive Z is 20% or less of the specified impedance then you should be cool.

Note that the autoformer will step up any impedance connected to the secondary, it is a TRANSFORMER, so the actual load might be higher than the impedance on the label.

A 6SN7 cathode follower should drive the snot out of most audio inputs, I should think. Just fire it up and rock on with your bad self!