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Someone should kick me in the keester

No matter how much I know and learn about audio, I can still be completely oblivious to some of the most basic things. Today I discovered a new dimension to that fact.

For quite a long time I've been complaining (privately) about the lack of detail, imaging, and overall clarity my system had, in spite of the quality of its components. I spent a bit of time swapping tubes, changing interconnects, and adjusting the speaker position without a great deal of success at cleaning up the sound or providing a solid soundstage to my satisfaction. While most of my friends couldn't hear the problems I described, I certainly did and it lead me to think that this might be as good as it gets.

A few weeks ago I decided to order some parts to build the Max Rochlin memorial digital cable, partly because I needed a project to keep me busy, and because it was the only cable in my system I had not yet replaced. I finally got around to building it this morning (for those that are thinking about trying it, it took me about an hour or so) and discovered after installing it that I had an entirely new audio system. The soundstage was right on the money and rock solid, the music was clean as a whistle (even through Moussorgsky's Pictures at an Exhibition), the bass tight, the midrange a thing of beauty, ... I could go on.

Anyway, it turns out that my suffering for the past year or so was due entirely to an inferior digital cable and nothing else. I had been very skeptical in the past about the differences a digital cable could make (bits is bits?), but I now stand both red faced and enlightened. I'm not entirely sure that I understand the physics behind the change I made, but it does seem that there are things about digital transmission that I need to brush up on.

Anyway, if confession is good for the soul, then let me be the first to give my spirit a lift :-).

For the record, the system is mostly CJ (17LS, Premier 12's, DA2-B DAC) with a Pioneer DVD as a transport.

-- Ken
kjg

Showing 4 responses by sean

sean
6,231 posts
 
Welcome to the "wire DOES make a difference with digital" club. I found this out simply out of necessity and kind of by mistake. I had purchased a DAC & Transport and thought i had a spare digital cable or two laying around. Well, when the gear showed up, i didn't have any spares. As such, i temporarily had to resort to using standard "non-digital" interconnects. Those i did have tons of, so i began to experiment.

I quickly found out that cables that had a definite "sonic signature" in the analogue realm carried that over to the digital realm. Taking this a step further, i began experimenting with different digital cables to find the same thing. 75 ohms or not, each had a slightly different flavor with various high and low points. I think that this may have more to do with reflected energy / vswr than anything else though. Just a guess though.

While i normally don't play "devil's advocate", i will on this one. Are you sure that "personal pride" is not playing any part of your "increase in system performance ? Have any of your buddies been able to tell a difference ? It's always nice to have an outside source verify your observations, especially if they have not been tainted with what to listen for. Sean
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sean
6,231 posts
 
Dekay, you have me REALLY confused. The way you described things, you have an interconnect that has a 60" center conductor with a 30" ground ??? If this is the case, either the center cable is coiled to equal the same distance as the other shorter cable or the cables do not run parallel to each other for their entire length. Either way, i would venture to say if either of those guesses is close, your cables are FAR from a nominal 75 ohm impedance.

The idea of different length conductors could help to "play games" with or "hide" standing wave based problems, but might also contribute to time smear.

Can you clarify what you were trying to describe to us ? Sean
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sean
6,231 posts
 
I'm pretty sure that i can picture what it looks like from your description. It sounds as if you've created some type of inductive load with non-symetrical loading between the polarities. Due to the "loops" or "knots", the hot side would see a greater percentage of this inductance. As to the rest of the cables, are they anchored together at any point or somewhat hanging loosely around each other ? The further that they are spread out from each other, the greater the inductance.

As such, it is possible that you've somehow created a "resonant trap" that is tuned close to the output frequency of the transport or a harmonic of it. Playing with the size and placement of the "loops" would alter the impedance, therefore changing the resonance or tuning of the circuit. The farther that you got away from the central beneficial frequency, the more the effect would "collapse". Keep in mind that this is strictly a guess at what's taking place.

One more question. Where in the world did you come up with this configuration ??? : ) Sean
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sean
6,231 posts
 
What is this "OTA" and where can i read about it ?

As to "low powered", the only system that i have that somewhat falls into that category would be my "antique" Marantz 8 (30 wpc). That amp may be going out the door soon in a trade ( of some type ) though. A local Marantz collector wants it, so who am i to deny his collection : ) Besides, it is very clean and does deserve to be "preserved" in his "Marantz Museum". Not sitting in my cold, dark basement.

Boy, how i wish i had the money for a TDR ( Time Domain Reflectometer ). This device can tell you just about ANYTHING that you wanted to know about a cable in a matter of moments. Then again, i don't happen to have $35K - $50K just laying around at my disposal : ( If i did, you can bet that i would be building cables professionally with very detailed specs to back them up.

With that point in mind, i have to wonder how many cable "manufacturers" ( or should we call them "re-packagers" ??? ) actually have "real" test equipment and make use of it ? I know that Ray Kimber does but as to any others, who knows ???? Sean
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