John Curl's Blowtorch preamplifier

[Wavebourn]

I'll go now to try to reverse one of my XLR cables to check if it will sound better...

Tried, no sound at all.

 

[auplater]

reversed cables

If I reverse the phono cables on my vintage phillips tt and play the infamous Beatles album, will I still hear the "Paul is dead" "daed si luaP" snippet in reverse, or will this show up whilst playi ng forward...

Sorry... couldn't resist😀 😀

 

[john curl]

I have known examples of audio reviewers being able to detect a single 'out of direction' coax connector in a whole audio system at CES that was not their own. I was there. Still, it is not something that I like to concentrate on. Metal and insulator purity is more interesting to me as I can study it more easily. We have had the same problems with connectors.

 

[PMA]

Anatolij, I wonder how you reverse the XLR cable - female to female?? No sound?? 😀 😀

 

[john curl]

PMA, it is next to useless to input about this stuff. We have compared notes successfully, however.

 

[Wavebourn]

Anatolij, I wonder how you reverse the XLR cable - female to female?? No sound?? 😀 😀

Absolutely no sound, Pavel! 😀 😀 😀

Conclusion: cables are directional!

Edit: sorry John; I did not laugh when proposed to measure non-linearities of cables made of different materials, but speaking of their directivity I certainly do laugh. Can't resist, sorry...

 

[Bas Horneman]

http://www.theaudiocritic.com/downloads/article_1.pdf

:bs:

 

[PMA]

PMA, it is next to useless to input about this stuff.

Okay. I did not know.

 

[john curl]

I hoped for better.

 

[PMA]

I really had one.

Let us go back to topic 😉 . John, I would be interested to know if you had any interference troubles with bare (unshielded) wires inside the preamp case.

 

[john curl]

Not really, but we do have to keep the channels separate.

 

[R-K Rønningstad]

Re: cable directionality

Here is another nice anecdote about cable directionality:

An acquaintance of mine (BS in electronics, pun intended) was unhappy with the sound of his system. When he connected the speaker cables the other way around, he observed a marked improvement.
That's not all. He also had a very plausible explanation: In the first case, the strands of the cable were twisted in the wrong direction, that is, counterclockwise when looking from amp to speaker. In the second case however, strand were twisted in the right direction, i.e. clockwise (again when looking from amp to speaker, of course)!

Then I really felt sorry for this poor fellow. What was wrong with his reasoning?

Maybe there WAS a real difference? Maybe he "accidentally" cleaned his connectors when doing the change. Hence it was really comparing apples and oranges?

 

[Edmond Stuart]

Yes, I guess so. But his explanation was just as stupid as attributing the effect to micro rectifiers for example.

 

[scott wurcer]

Re: reversed cables

If I reverse the phono cables on my vintage phillips tt and play the infamous Beatles album, will I still hear the "Paul is dead" "daed si luaP" snippet in reverse, or will this show up whilst playi ng forward...

Sorry... couldn't resist😀 😀

I've listened to the "I buried Paul" cut and remain unconvinced.

 

[PMA]

White double?

 

[SY]

Re: Re: reversed cables

I've listened to the "I buried Paul" cut and remain unconvinced.

Turn me on, Dead Man.

 

[john curl]

There is a difference between a diode and a dead zone. However they can both cause xover distortion.

 

[Wavebourn]

There is a difference between a diode and a dead zone. However they can both cause xover distortion.

So, using a kilometer of a wire we can detect that dead zones by measurements, right?

 

[john curl]

Maybe, any ideas?

 

[Wavebourn]

Maybe, any ideas?

I have a dozen of 100W transformers with 10K P-P primary, let's put'em in series and measure. I think it is plenty?

For Faraday cage we may use my bulletproof safe.

What voltages/currents should we use?