John Curl's Blowtorch preamplifier part II

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I don't know either, but for some reason as I look ahead on my audio journey I see fully balanced as my final destination - I think I have a ( possibly irrational ) attraction to the elegance of the symmetry - everything about balanced just seems to make sense - with the possible exception of dominant 3rd HD but I'm hoping I won't mind that.

I'm in the same boat, listening to a fully balanced mega million setup in about 2 weeks , I will let you know if i see the light, not in PC Franks realm , but i was told it's good .. :D
 
I understand the attraction to the fully balanced configuration but it seems if you use any single component that is not balanced, some single ended component anywhere in the chain is it really the end all of the system? Won't you still get the majority of the advantage even if you used say a single ended cdp or turntable at the front end of the system with some way to connect to the balanced system?
 
Here, for reference, are distortion plots of an ADC using three different supplies. The first is a Jameco linear supply kit. Its pretty crude and has more ripple than an regulates supply should. The second is a packaged Sola linear supply and finally a little Cosel switching supply. The opamps on the ADC board (AKD5394A) have no local regulation and only nominal local filtering. I was very careful with the grounding. The source has some hum in its output from leakage and supply ripple.

The conditions were not identical but similar and the plots will have different averages etc. so don't read the differences as due to the power supplies alone.

I could find no reason not to use the little switchers in this application even with such a stringent THD+N capability.
A little local decoupling and use the cheap one they all look good enough with a little local filtering . how do they sound ? jan article on power supplies showed some discontinuity between sound and spec on the power supplies that is why i inquired about the sound . ;)
 
I'll try again:
 

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Here is my simplified view of individual snubber caps versus a single one on the secondary. Pretty obvious of course but helpful to some of us. While going through compliance testing experiments I found the single cap works much better than the four caps. Not sure why I stopped thinking when the test was nicely past. This and the soft fast diodes were the best arrangement, you may want a small value resistor. The measurement setup is a standard LISN feeding a preamp and a 1 GHz spectrum under PC control for the proper timing and averaging sweeps.
 

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The local catastrophic flood situation is drawing to a close - hopefully. The last flood wave is expected to arrive tomorrow night or early the next morning, and has the capacity to flood Serbia's largest power generating facility in the town of Obrenovac, some 40 miles east of Belgrade.

The whole town, some 20,000+ people who have not been evacuated yet, have been moved out today on the orders of the minister of interior affairs.

Two days ago, they asked for 1,200 volunteers, and had to stop counting after 4,800, because they simply don't have the logistics required to accommodate all these people.

It's almost surreal to see locals, the cops, the army working side by side with Russian Special Forces (highly trained in offering quick relief in disaster areas), and solders from Macedonia, Montengero, Croatia (itself also flooded, but much less), Slovenia, Hungary, and so forth. Many countries have either sent relief in form of tents, water pumps, inflatabe boats, food and medicine, including of course Japan. Serbia has never had any close ties with Japan, yet those people have helped us at every turn, which is why I say "of course".

The offical EU bodies from Brussels issued a statement that as a candidate for joining the EU, Serbia is entitled to use EU's emergency relief funds. No idea how much that is, but it is a good gesture.

Abu Dhabi has pledged $10 million for quick relief.

Novak Đoković, the tennis ace, has turned over his entire $500,000 winnings to the relief fund.

The extent of damage has to be seen to be believed. Entire villages have been scrubbed from the map, they exist no more. The damage in livestock will force us to import meat rather than export it.

I saw a video clip today on TV which really said it all. A dog was swimming for shore, with a cat sitting on his head. You don't see this every day.

My home was also in turmoil today. Wife and I turned over every nook and cranny to find whatever we could spare, such as blankets, clothes, shoes and such like. Towmorrow, I go shopping for 60 lbs of detergent, also badly needed, pack it all up and take it to the nearest relief center for coordinated distribution.

For a closer look, and if you are feeling generous and wish to donate, take a look at FLOODRELIEF #SerbiaFloods #SerbiaNeedsHelp.

Thank you.
 
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