John Curl's Blowtorch preamplifier part III

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I still would like to buy the cables which some here say have directional affects........
I only heard directionality on 3 out of many cables, 2 with el cheapo plastic semi transparent green and violet the other with a bit nicer black wire with magnetic gold tinted metal connectors. All were RCA to RCA obtained locally from electronic component shops and I noted directional difference on sibilance on Dolly Parton's "House of the Rising Sun" and Norah Jones' "Don't Know Why". No measurement attempted, I simply discarded the cables due to suspicion of defect. But it seems that Dan has access to more reliable sources of directional cables. Perhaps he can help you.
Try end for ending an unbalanced coaxial guitar/bass cable, while you are at it try a few other such guitar cables with similar/blameless LCR values but differing dielectric and differing sheath insulation materials, usually polymeric and of diverse range including extenders/additives/pigments.
Repeat the above for decent quality/blameless and seemingly similar RCA terminated Interconnects.
Modern off the shelf cables are typically same/consistently/perfectly prepared and terminated and at least some will cause systems to reproduce sound subtly differently, and further direction of such interconnect cables will further cause the system to reproduce sound subtly differently. ...
 
Chris,

The Avro Arrow was the most advanced fighter of it's time. The prototypes were actually built on a production line. The line was then modified as the prototypes changed. This was done to save time, definitively not money. as the USSR's Bison bomber was thought to be a major threat.

The engines targeted for it were not ever produced by others, again Canadian ones were designed for it. They used titanium for the second stage compressor fans. A great choice of metal except the source was the USSR. It also had the problem that they did not have good ways to work with the metal so that really raised the costs.

Then as this was implementing essentially what we call fly by wire systems for the first time, they had neither the experience or even the parts to do a superb job. However keep in mind the plane was designed before silicon transistors, so they did get it to work, but it was again quite expensive to build and was a bit of a reliability problem.

Then came the issue of the avionics, radar and fire control. A Canadian design attempt was abandoned as too costly and the RCA alternative designed in was never put into production. So another cost increase to refit to a much less capable Hughes system.

Now it would have been the first operational Mach 2+ aircraft had it gone into service. But for the mission on intercepting Bison bombers which were only slightly faster than a P51 piston aircraft, they were an expensive bit of overkill. Then the issue was the original over estimate of the number of Bison aircraft. The Soviets in displaying them in public would have them circle around many times to make it appear they had lots of them.

During the rush for the Avro Arrows design they thought there would be almost a thousand of them. The actual production of all models was less than one hundred.

Yes the Canadian military really wanted them, but the politicians though the money would be better spent on missile defense program.

The real death knell was of course no foreign sales. The US was not invented here unavailable, the Brits thought they had invented all this and could do better and no one else would be allowed access to all the secret sauce.
 
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Which is why I was asking.

I'm not a cable is directional believer but I can see connectors and shields doing something, maybe, we have seen these items already posted.

Even with my words above I've spent enough time in the studio with 50 foot mic cables carrying mV signals.... It's going to take a lot to convince me.
 
You think you can claim victory with a cheap insult?
Not intended as any kind of insult, please don't take it that way.
Proof is the one thing that is totally lacking with all your ideas.
The measured proofs will come soon enough, in the meantime I encounter and investigate for myself subjective findings that others also have spoken of in the past.
Others have given suggestions on how to discriminate this cable directional property, and when results are shown there will be a rational explanation of course.
I don't lose sleep over this, but I do consider it to be a strong variable/confounder in the case of some audio systems and requiring qualifying.


Dan.
 
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All this cable talk;
Is this for single ended or balanced?

Has anyone stated a balanced cable is directional?

Mike
XLR cables aren't straightforward to use in arbitrary direction because of the gendered connectors. Unless you have gender-changing adapters people have little chance to test for potential XLR cable directionality, so not much info to be found.
I know of at least one semi-pro cable maker who states directivity for the raw cable material he uses for XLRs.
 
Or even: is solder wire directional? If not why don't people make wires out of it so they don't have to worry about the issue? But if it is, how can you tell after it melts? If it creates a blob, is the blob directional? If so, how can you tell which end of a circular blob is the input and which is the output? What do you do if the center of the blob is one of the terminals? If a cable is directional, does that not imply a difference in electron transport in each direction, and if so does it cause a cumulative DC offset? I know for a fact that at least two of the manufacturers of "directional wire" have no clue what direction the strands were drawn in order to infer any directionality. Apparently I don't have as good an imagination as some others here because I can't imagine why these effects would happen at the bulk atomic level and cause audible issues...and if this subject is merely mental masturbation, what does the climax feel like? Interested minds want to know!

I found it at least interesting to see discussion of possible real world audible issues such as the IMD when passing highly complex signals through DAs...or is that too pedestrian? One of the things a device much maligned here called the Pono Player can do is sound extremely clean when decoding mixes which are congested compared to other DAs I have like the Dragonfly which sounds pretty good under most other circumstances. My fave to date is the Auralic Vega, but it costs 10x the Pono for a bit higher output voltage and transparency depending on which filter type is chosen for which kind of music. Do others have this experience with differing DAs? Any solid evidence from testing and listening as to what causes the difference?

Howie

i wonder if PCB traces are directional?
 
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