John Curl's Blowtorch preamplifier part II

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I still wonder to this day if he ripped off a cable design I'd done back in the 80s.

I'd taken some 16 gauge insulated wire and pulled out the wire to use as a core. Then I took about four strands of 30 gauge wire wrap wire in parallel and wrapped them helically around the core for one of the cable's conductors, and repeated the same thing in the opposite direction for the other.

This was written about on The Audiophile Network, a popular audio-themed dialup BBS back in the 80s. The posts about the cable design were even archived in the file area of the system when it was upgraded from the old Apple ][e that it had been running on.

A year or two later, XLO came onto the scene with a cable that used the exact same design.

Skoff doesn't strike me as the most imaginative person I've ever encountered, and doesn't really have any background in electronics, so I've always wondered just how he came up with the design for his XLO cables.

se
 
Technically speaking why would you do this?

Oh, some were going on about cable capacitance and I just noodled around one afternoon with an idea for a low capacitance design. I never even made a complete cable from the design. Just put it out there for the DIYers to play with is all. It was never anything terribly serious. The idea just popped into my head one day so I just put together a simple proof of concept and wrote about it.

se
 
Technically speaking why would you do this?

It's an exercise in sailing as close to the wind as you possibly can. Why anybody would want to sail close to the wind in as dubious a business as audio cables I can only imagine. Create a product to leverage every audiophile myth in existence, without actually stepping over the point of making false claims. That'll learn 'em.
 
It's an exercise in sailing as close to the wind as you possibly can. Why anybody would want to sail close to the wind in as dubious a business as audio cables I can only imagine. Create a product to leverage every audiophile myth in existence, without actually stepping over the point of making false claims. That'll learn 'em.

Dude, it was just a silly idea I had a little fun with back in the '80s, no more, no less. Had absolutely nothing to do with "sailing as close to the wind as you possibly can."

se
 
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@ John what are you showing in the plots?
Noise on the electrical outlets from the
power that you are using?

@ Richard how do we measure this again?
It will be helpful to me and others.

Nice Vehicle by the way. Now that I've finally
seen it. Getting ready to work on mine again.
Yours is a bit more refined than mine, more
of brute force guy I am w/a lowly Malibu
2 door Chevelle SS396.

Is the Bently yours too? Have you been holding
out on us?


Hi,

I use several items to look at the frequencies on the ac power line: One is a wide band inductive pickup into a network/spectrum analyzer.... Anritsu (10Hz to 30MHz). I can just place the pickup/sensor near equipment or against an ac power cord and pickup the info. Another is current or voltage harmonic directly off a Fluke 43B for low freq harmonic/freq analyzer and various other equipment, like Extech Earth Resistance tester, clamp-on ground resistance tester, common-mode and differentail-mode signals are loked at. A power probe model 115 by Power var is helpful over a limited freq range, etc. Many other equipment as well.

The SS 396 is a nice car. Good HP/Wgt ratio. And, lots of mods for it's suspension, brakes etc. Yes, the ZR1, CTS-V and W12 twin turbo Bentley are my toys. Lisa gets a PT cruiser.... non-turbo model because she has such a lead foot, she would be dangerous in anything stronger than a PT. :)


THx-RNMarsh
 
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That's me, open minded like Roger Skoff! '-)
Since SE brought the subject up, I thought I might show a few distortion measurement comparisons, these photos being the harmonic analysis of a 1KHz tone, with two DIFFERENT audio connecting cords, both 1M long, with essentially the same capacitance, and therefore characteristic impedance. Why did one upset the analyzer so, IF that is the cause? Or is it in the cable itself? That is the question.
 
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Yes you and other's have made this very clear many times. Nothing of past experience will be revisited and re-examined ever, nothing new will be learned. There apparently is as much to lose in this as in two sides sitting down together in a listening test where both sides have an equal chance "to get it wrong".

Well, now listening tests is a whole other game. i dont mix the two or 'sides' as you call it. The distortion when voltage drop is across it is measureable and I think the distortion is caused by the dielectric material primarily. You can rank order distortion, generally, by DA if you like.

But I have done my own listening and once with JC at a Berkeley guys house where he executed a dblt to us. I'll let JC tell that result if he likes to. I just stay out of listening tests results because they are so hard to do well and are very narrow in what they test for and can conclude. For myself, I would rather listen to what a thousand others say about what they hear as a consensus... right or wrong consensus opinions matter and can be helpful. There are some things i cannot hear, of course, and sometimes it is between two film caps. I have done some very hard listening and after several hours of going back and forth come to agreement with others about the differences.... but, I know at that detection level, it wouldnt show up if I did a random dblt.... and it just isnt that noticable nor that important to me. So, I just buy any old reasonably made PP. Speaking for myself, only, of course.

Because it is such an emotionally charged subject, i just stay to what is measureable and let others decide for themselves if that 'something' is significant or not. You get to decide. I wont do that for you. And, I dont care what your conclusions are, either. I dont make cables or caps or pcb or anything which would matter or bias me or make me want to protect my income source.

I think you guys ought to take up what is audible or not with those who advertise materials to sell their products. Start with going all the way back to Walt Jung or others who say they heard this or that. I stay out of that 'game'. I am interested in the esoteric stuff and very low distortions... maybe they all add up to something greater than one tiny piece of the whole?


THx-RNMarsh
 
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Because it is such an emotionally charged subject, i just stay to what is measureable and let others decide for themselves if that 'something' is significant or not. You get to decide. I wont do that for you. And, I dont care what your conclusions are, either. I dont make cables or caps or anything which would matter or bias me or make me want to protect my income source.

I think you guys ought to take up what is audible or not with those who advertise materials to sell their products.


THx-RNMarsh

And yet you are happy to bang the HD drum as being 'clearly superior'? How does that tally?
 
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