John Curl's Blowtorch preamplifier

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Re: 99.99999999 pure &^%#$

auplater said:
no... the problem is most all copper used for electronics is already low oxygen... Even if you buy special OFHC grades... it's still cheap relative to what the connector folks are charging you for the finished product...

Exactly!

all the 6 nines pure ofc pablum is designed by marketing people to separate your wallet from its contents... 😉 😉

John L.

Again, exactly!

BTW, a little bit of oxygen improves the conductivity. See again: http://www.diyaudio.com/forums/showthread.php?postid=1583351#post1583351
 
Re: why not??? here's why...

auplater said:


well... for one thing, non-plated nickel has an oxide barrier on it that develops a high (and unstable) surface contact resistivity, ... you know.. ohms/square that sort of thing...

http://www.esdjournal.com/techpapr/ohms.htm


John L.


Hi John,

That's makes sense. I stacked five 3-volt (1 inch) lithium coin cells (nickel plating??) and even with pressure from a battery clip they measured only 11 volts instead of 15 volts. I used a silver contact enhancer on each one to get the desired/correct voltage. I was surprised by the amount of contact resistance.
 
I was watching class A movie, detective story made in Europe, set in Denmark. It is something that I watch every week. I can't understand the language, usually, it is either, German, French, Italian, or Finnish or Danish, or Swedish, so far, but I have to rely on the sub-titles to make any sense of it. However, EVEN a low level sound associated with the actors, etc, gives me the 'tone' of the conversation and makes it much more interesting. This is WHY I bought this $22 'wonder' in the first place. So I could glean that minimal information, without upsetting the lady in the next apartment. On Monday, after she knocked sternly on the wall, I turned off the sound, completely, and TRIED to enjoy the SAME movie. I just couldn't do it easily, without any sound at all.
 
Oh, I'm sorry you are in this situation. Last time this happened to me I eventually just did what I pleased but that was 30 yr. ago. It's amazing how well it works when you convince the other party that you are going to do whatever you please and you simply ignore them. There are sound levels set by ordinances you are probably not exceeding them.
 
As connectors came up: does somebody have a suggestion for well made RCA/Chinch connectors?

I mean also mechanically well done 😀 , that is secured against twists which may happen with plugs that have very tight contacts.

The standard construction using a thin plastic disc does not make me very happy (a la Neutrik RCA and a lot of other products being basically the same), I found only WBT-connectors that seem to be really bullet proof in this regard.

http://www.wbtusa.com/pages/0244m.html

They are, however, expensive (about 18$ per connector).

Have fun, Hannes
 
h_a said:
As connectors came up: does somebody have a suggestion for well made RCA/Chinch connectors?

I mean also mechanically well done 😀 , that is secured against twists which may happen with plugs that have very tight contacts.

The standard construction using a thin plastic disc does not make me very happy (a la Neutrik RCA and a lot of other products being basically the same), I found only WBT-connectors that seem to be really bullet proof in this regard.

http://www.wbtusa.com/pages/0244m.html

They are, however, expensive (about 18$ per connector).

Have fun, Hannes

Hannes,

I've been using WBT and indeed they are superb, the best I have found yet, but expensive. Lately I manufactured a few cables with the Neutrik RCA plugs with the moveable sleeve/ground bush. These slide out and make ground contact first, then when you push on they retard and the center pin makes contact. Gets completely rid of hot make/break noise.

But the point is that the moveable sleeve has a clamping mechanism, not easy to explain but clear if you find a picture. It gives a very tight fit while still being able to move slightly when the cable is moved. The latter is also important as it helps prevent cable breaks right at the connector. I'm pretty happy with them, YMMV. In Holland they cost about 15 euro/pair.

Jan Didden
 
Hi Jan,

thanks for your reply!

Seems I could have been clearer: I was talking about the female connector to be mounted to the enclosure.

I do know the Neutrik (male) plug, nice and a bit expensive. Brings quite a bit of pressure onto the female RCA. So if somebody twists the plug to get it easier out of the female RCA (quite common habit I would say) the female RCA gets twisted (rotated) as well and can mess up the wires that are soldered onto it on the backside.

The WBT seems to be the only part that really prevents that; the Neutrik female RCAs just use a thin disc between the connector and the enclosure. This disc is pressed against the enclosure by fastening the mounting nut on the back; not a very sturdy solution IMHO.

It already happened that the nuts got loose and the whole thing rattles happily.

Have fun, Hannes
 
h_a said:
Hi Jan,

thanks for your reply!

Seems I could have been clearer: I was talking about the female connector to be mounted to the enclosure.

I do know the Neutrik (male) plug, nice and a bit expensive. Brings quite a bit of pressure onto the female RCA. So if somebody twists the plug to get it easier out of the female RCA (quite common habit I would say) the female RCA gets twisted (rotated) as well and can mess up the wires that are soldered onto it on the backside.

The WBT seems to be the only part that really prevents that; the Neutrik female RCAs just use a thin disc between the connector and the enclosure. This disc is pressed against the enclosure by fastening the mounting nut on the back; not a very sturdy solution IMHO.

It already happened that the nuts got loose and the whole thing rattles happily.

Have fun, Hannes


OK, I see. Yes, I have no recommendation then.

Jan Didden
 
These Neutriks at least should not start to rattle.
 

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