John Curl's Blowtorch preamplifier part III

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The light blue color gives it away; I've got a bunch of them because they're cheaper than dirt, but I haven't done any listening yet... :(
For sure they are the cheapest Jaycar could find, I think they're okish but a bit excess noisy (a bit grainy) perhaps.
It seems that resistor noise is critically important in this out of audio band cable termination role....counter intuitively perhaps, but the definite sound of CF reinforces this finding.
I agree the CF types sound a bit dull, and these field battered old ears need a bit of a boost in the upper end. :)
Thanks I will take your CF opinion as confirmation of my findings.
I insist on extended but clean highs like I hear in real life like clinking glasses, rattling cutlery etc, dirty highs or wrongly boosted highs drive me out of the room despite my well seasoned hearing apparatus.
I find as my system improves so does my hearing.....as the system gets better the ears relax more (totally) and that then provides better discrimination of fine sounds and differences.
I reckon this termination resistor experiment is an experiment worth trying, I would be interested to hear your results on any speaker.


Dan.
 
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Wilson big bux loudspeakers have crossovers filled with capacitors. Now, that is a place where caps can do some real harm, because there will be significant voltage over them. Plus, the ratio between load and capacitor parasitics will be much worse than in a coupling situation.

Thats very true. Very critical place for caps. Usually bipolar electro in may cases. Wilson Audio has always used the best of REL-CAP. :)

Since Dave died and Bas Lim wanted to retire, Wilson Audio owners/investors bought REL-CAP . They could not get better cap anywhere else if REL closed. They are so important to the over-all performance. But, they are not cheap. Espec if you need large values.. The new owners called me and ask for permission to use my info and writings. I said yes, no charge.


BTW -- This is another example of my M.O. I told Bas Lim on the phone conceptually how to make a really high performance film cap. he did the details by modifying one of his machines after staff went home. He sent me for measuring and doc some samples and showed it was superior. We applied and received a patent. Bas Lim then spent $40K (back when 40K was a lot of money) for a custom machine dedicated to make my design idea. Bas has a PHd in material science and has made the best caps for decades. He isnt fooled and T&M convinced us it was better.

I had received royalty for the life of the patent from REL-CAP.


THx-RNMarsh
 
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Not carbon film, but carbonized, for sure.
(8 watts of dissipation in 0.5W resistances ?)
I ran the system flat bickie for extended period this afternoon, both speakers still sound the same as each other, I will open the boxes and double check the resistors tomorrow.
Previous tests did not burn any resistors on music.

Ah, ok. What about this, instead ? YouTube
I played all kinds of stuff from classical to guitar/vocal to hard rock to heavy duty club music.
I will try the Beatles track tomorrow too. :).
 
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Tip: Just go to the closest pole from your location (North or south), hold the resistances vertically in one hand by their tails, and let the rotation of the earth twist them in the direction it wants.
YouTube

I find the twist using that technique is not tight enough. You need to keep each loop at least 1/10^7 shorter than the highest audible wavelength the speaker will encounter. BTW Dan, MF are not suited to damping duty. Challenge for you: cN you work it out? ;)
 
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