John Curl's Blowtorch preamplifier part II

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Recent experiment...I transferred the same MP3 file twice to a USB thumb drive, one with my filter surrounding the thumb drive pcb, the second without the filter.
The file is a Robert Johnson recording....ultimate in surface noise, embedded excess noise and overloads.
The result is that on playback using a shelf system with USB input, the 'filtered' version is much more agreeable sounding.
The recording surface noise is subjectively changed and reduced, and the embedded noise images to pinsharp centre, as does the musical content.
More low level room acoustic detail is evident, as is more correct timbre in guitar and vocal, and much better 'expression', and the barky/clipping sounding higher levels are pretty much cured.

Any ideas on what's going on.....bits is bits ?.

Dan.
 
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Making things out of stainless usually triples the cost compared to regular steel. The advantage is obvious. What is not so obvious is how it reacts to seawater. Depending on alloy some will actually rust. Others will stay bright and shinny up until they totally fail. But I suspect the builders chose the right alloy and expect about 100 years until failure.

Now most of my use is alloys 303 or 304. Punch life is much less than normal by a factor of about 2. Bending is no issue in the thin gauges I use. Have hade some panels outside by the Great Lakes for 30 years.

I have seen the stainless steel 1930's demo cars. Looked fine except for the dents and dings. Hard to repair. You need a real good panel thumper and there really aren't any in this country.
 
Making things out of stainless usually triples the cost compared to regular steel.

Steel plate is around $1350 per metric ton, SS does $12,000
(wholesale, ex sales tax)

Lars is an icebreaker, both bow and hull are ice class, the shape of the hull pushes it onto the surface if enclosed in ice on all sides.
Can do a return trip Rotterdam - New York on a single tank of fuel, with 10% reserve.
 
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Recent experiment...I transferred the same MP3 file twice to a USB thumb drive, one with my filter surrounding the thumb drive pcb, the second without the filter.
The file is a Robert Johnson recording....ultimate in surface noise, embedded excess noise and overloads.
The result is that on playback using a shelf system with USB input, the 'filtered' version is much more agreeable sounding.
The recording surface noise is subjectively changed and reduced, and the embedded noise images to pinsharp centre, as does the musical content.
More low level room acoustic detail is evident, as is more correct timbre in guitar and vocal, and much better 'expression', and the barky/clipping sounding higher levels are pretty much cured.

Any ideas on what's going on.....bits is bits ?.

Dan.

If the digital information in the files is the same then the data contained within is the same end of story, there is no difference... or else you are going to be awarded a Nobel prize....
You need to go to Computer Audiophile and talk to SandyK.
 
Steel plate is around $1350 per metric ton, SS does $12,000
(wholesale, ex sales tax)

Lars is an icebreaker, both bow and hull are ice class, the shape of the hull pushes it onto the surface if enclosed in ice on all sides.
Can do a return trip Rotterdam - New York on a single tank of fuel, with 10% reserve.

Not around here! I would scream if steel went above $500 US ton and 303 stainless $1,600. (Although it has been a while since I last bought 303, running low so may need to do so this year.)

Of course they do make it here.

My biggest price issue is that the minimum shipping is $300 for any load and $1,250 for 20 tons.

I usually buy a minimum of 2 tons at a time. That is just a bit over 4 cubic feet! My supplier knows to place spacers between every 2 tons as that is my forklift's capacity.

If you are paying that much for stainless it had best be one of the higher performance alloys like 316. (The story was of one grad student who needed something made so he specified 316 stainless, as the was the "Best." When priced out and properly specified he went with 304. An almost ten times cost savings.)

Just for Jacco, my last use of stainless was a few weeks ago. We planted three sapling trees. The last three tries on planting trees someone drove their 4 wheel drive truck onto the lawn and over them. So I put up a rabbit fence around these. 1/8" x 3 inch wide "Inverted V" shaped stainless steel pieces ground a bit to sharpen them. Should keep out the rabbits. 🙂 (No evil grin emoticon!)

I do have a security camera monitoring that area so I can replay the rabbit action.
 
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