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
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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Ezmerelda: A 75 ohm cable (true or otherwise:-) is not always needed for quality digital. My two best sounding digital IC's are neither. I am not quite certain as to how to measure the length of one of them as the Hot lead is 60" long and the Cold 30" (figure 90" or approx. 2.0 meters in the signal path). One IC is a Mapleshade Double Helix (this one is 1.0 meter) and the other is fabricated out of the 47 Labs OTA cable. Both are superior, IMO, to 75 ohm cables that I have tried (with some of these being very popular and costing a great deal more). I have never had decent results, for instance, taking a single standard analog IC and using it in this application, so there is something more involved in making a good digital IC, but I do not feel that it being 75 ohm is necessarily a part of it.
Ezmeralda - The cable I replaced was fairly generic RG-59 coax with relatively inexpensive audio RCA connectors -- likely not a 75 ohm connection. The new cable uses Belden 1506a coax with 75 ohm Canare RCA and BNC connectors. Its hard to say specifically where the differences lie, but in every area the new cable is certainly higher quality than the previous one. And, aside from an hour of my time, the total cost was about $20. Not a bad value.

Sean - You're right in pointing out that the improvements I'm hearing may well be manufactured by my overly swelled pride. As yet, I'm the only one who's listen to the system since yesterday so its tough to know for sure. However, the changes I'm hearing are not subtle, and the problems I've had in the past were very specific and easily recognizable. After a night and most of a morning's listening, I'm happy to say that many of the issues I've had have either been eliminated or significantly reduced, and the system is now overall much more enjoyable to listen to. To be certain, I have a few friends with reasonable ears coming by tonight, so I'll reserve final judgment until then.

To be specific, these are the changes I'm experiencing:

1) I've always had a problem with "unstable" deep bass - that is, sustained bass notes that would waver continuously in volume, and sounded "impure" - almost as if the tones coming out of each speaker were slightly different. My example for this is Arvo Part's I am the True Vine where the vocals are accompanied by steady organ pedal tones. With the new cable, these notes are both entirely stable and beautifully pure. This is a major improvement.

2) Complex musical passages, such as the last movement of Pictures at an Exhibition or Jupiter from The Planets have always been muddied to the point of being distorted. I had attributed this to deficiencies in the DAC, but having heard both of these pieces sound very nice with this DAC in other systems, I was a bit skeptical. Both of these pieces are now very clear, with the individual instruments being well defined and easily recognizable (including the giant bell at the end of Pictures, which is now actually a bell).

3) The placement of instruments and voices within the soundstage were often difficult to pinpoint, and when found would move about quite a bit. Now, not only are the positions of the musicians solid, but there is a well defined difference between being in the correct listening position, and being outside of it. Previously, changes in listening position made very little difference in the overall sound.

I'm willing to believe that what I'm hearing is all psychological and that objectively, things really aren't any different. If all it takes is an afternoon project and an over inflated sense of pride to improve my listening experience, well, I'll be happy to keep it up ;-). However, I'm inclined to believe my ears in this case and appreciate the difference that a better digital cable can make.

Thanks for all of your comments about my epiphany. And now that I have my soldering iron out (and another successful diy project under my belt), perhaps its time to take Brulee's suggestion and try building some better quality power cords. At the very worst, it'll keep me out of trouble for a while :-).

Thanks all,
Ken
Hi Ken; I'm glad to hear that such a simple change has made such a big improvement in your system. I can identify with your findings re digital cables. I now use a Cardas AES/EBU digital cable between transport and DAC (both Levinson). The Cardas is very "musical". The only other one I've tried is a Levinson AES/EBU, that I expected to be a very good cable for their own components-- not so-- it was detailed to the point of being analytical and PRaT was really poor. It was a simple change (and both cost about the same), but with the Cardas, the improvement in quality/character of music was huge. Thanks for sharing. Cheers. Craig
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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