John Curl's Blowtorch preamplifier part II

[jneutron]

Originally Posted by RNMarsh

TEKtronix expected professionals to be doing the trouble-shooting,repair.....

Leaves me out...

Originally Posted by RNMarsh

Speaking of ferrous metals and their non-linear Z affects - Nickel - it is also used to plate over copper before gold plating -- pcb traces, for example. If JC was building this opamp - he would use purest copper and gold directly on it - all on specific Teflon base material. Then use best soldering alloy, temp control and flux with no residue. A purist approach. -RNM

Hey, that's him..

No residue flux?? Man, I hate that stuff. Easier to just clean the daylights outta it. Just watch out for poly caps and solvents...

jn

[MikeBettinger]

Originally Posted by SY

If they're so easy to discern, why do they disappear in the test formats where people are easily able to distinguish tiny differences in level and frequency response, as well as data compression, phase, and polarity. Why do you not trust your ears and somehow need nonauditory cues?

If you can't hear it using your ears alone, you can't hear it.

I'm not sure I understand your response. I'm not concerned about test formats. I'm commenting on taking a reference and switching in another with a difference and being able to hear the difference. A simple apples to apples approach. The point was to trust your ears and also that simple differences do exist.

My point about double blind was that in a personal situation, where it is not a "test" and there is no right or wrong, just listening for difference as you switch is the goal. Sorting out what it means comes with extended listening. I do this all on a personal level so the results are for furthering my own enjoyment. If I fool myself I find out when I put on something I'm familiar with and it sounds worse then the last time. Then I know I have to back up or figure out what went wrong.

Regards,
Mike

[MikeBettinger]

Originally Posted by john curl

Mike, your heart might be in the right place, but relative to the CTC Blowtorch circuit, it just does not work the way you think it might. There are NO mods that could improve the overall quality of the design, only compromises are possible. It's like saying that anyone can build a V12 engine for a name sports car. Just give the basic design to the local mechanics and they will perhaps 'improve' it. '-)

Hi John,

Wow, I find this an interesting response.

Half perfection acheived and half your a local mechanic thinking a few little tweeks will improve on the basic design. I never mentioned the Blowtorch, and I as a rule hold that everything about any design was done for a reason. My understanding of things goes a bit deeper than it appears on the surface.

Regards,
Mike

[bcarso]

Originally Posted by jneutron

No residue flux?? Man, I hate that stuff. Easier to just clean the daylights outta it. Just watch out for poly caps and solvents...

jn

I used to call "No-Clean" flux "You Had Better Clean" flux.

[scott wurcer]

Originally Posted by bcarso

Donald is a bright guy with a day job, and a degree from Caltech, where he was influenced deeply by Jim Boyk.

I took my daughter 5 or 6 yrs. ago to visit the campus (you think MIT was nerdy) and when I called Jim's number I got a very sad sounding message that his special post was eliminated, just economics?

[john curl]

Stick with modifying VW's Mike! '-) Don't try to change the big Porsches, et al. Unless you do it for a living.

[john curl]

Richard Marsh give me a good way of expressing it:
The higher developed a design (be it electronics, autos, or whatever) the less you can 'contribute' to improve it. I agree.

[bcarso]

Originally Posted by scott wurcer

I took my daughter 5 or 6 yrs. ago to visit the campus (you think MIT was nerdy) and when I called Jim's number I got a very sad sounding message that his special post was eliminated, just economics?

I don't know all the details, but I would say "politics and economics"

Don still talks to him and has been trying to encourage him to do more recordings, but I gather he's pretty bitter and negative these days. He did make some good LPs (I have a few of them) although (as he agrees) the tape machines and other electronics had a lot of hiss.

[morinix]

Originally Posted by john curl

Richard Marsh give me a good way of expressing it:
The higher developed a design (be it electronics, autos, or whatever) the less you can 'contribute' to improve it. I agree.

In theory based on what I understand on this thread would not mesh socks around the passives allow for a better ground at high frequencies? Given that to be true since the Teflon PCB is not a DIY reality and normal PCB's are inferior then point to point would be the only option as a low parasitic assembly option. Since the components are sockable when done point to point and this would be a time intensive endeavor any way..... This would not be an improvement given the constraints? or am I just a pain in the booty?

[john curl]

You are just wasting energy. It is best to use what is practical, and not worry if 'better' is possible, like Teflon.