Actually I get 85% of market for scrap gold included!
I knew I should have included the
when teasing you about anecdotes. Seems you need a weekend to unlax. (you can only relax after first unlaxing!)Scott,
I should have said their ain't no microdiodes causing distortion in copper wires that I have measured. I thought it was clear that carbon composition resistors are made from raw coal and do contain crystals and other fun stuff.
That is why in the 60's when they first upped the quality of resistors they concluded that there was enough individual variation among a single production run they would have to be tested individually.
As soon as film resistors became the norm these issues went away.
Actually I use it all and them trim it as a long piece to use as a buss bar in dead bug type projects.
Throwing out lead solder wicked into scrap technically is a no-no.
ES
We have isolated sections of the lab where all lead is forbidden, all the scrap from the rest of the lab is considered to be contaminated.
My point with the resistors was that I remain skeptical that an A/B even with say a 6db pad made out of 2-1K .01% Vishay S102's and one with one 1/8 W 1K carbon film and one Vishay would be easily detected at full line level. This test is nice because the level matching could be perfectly set by instrument.
No point in offering a challenge, for years one or the other party has backed down.
EDIT - Ed I doubt that Allen Bradley was using raw unprocessed coal in the 80's to make CC resistors. BTW the 40 yr. old 27Meg ones measure 40Meg! So I suspect all these resistors have bad moisture incursion so all bets are off as to what is going on chemically in them.
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Just as an independent input on the issue, measure some Alan Bradley pots (square package) sometime, with a relatively low impedance resistor on the wiper as a load (perhaps 1/2 pot value) and see what distortion you can find. Not all pots are this bad, yet some others can be worse. Carbon nonlinearity is in there somewhere.
Now before someone criticizes me for loading the wiper, I wish to pass the blame to Dick Burwen, who gave the idea to Mark Levinson in the early 70's. I just found the problem with doing it.
Now before someone criticizes me for loading the wiper, I wish to pass the blame to Dick Burwen, who gave the idea to Mark Levinson in the early 70's. I just found the problem with doing it.
I assume you mean by listening tests.
My stance on that is that if someone does the test and tells me they can hear the difference I have no trouble with their beliefs. I will still design by measured results.
I don't know what Allen Bradley was using. The resistors made locally use selected coal. The basic process is grinding it small enough!
I do have a customer in the activated carbon business, They use plain coal from only certain mines.
I think it is like salt. The stuff that grinds up and looks white becomes table salt, the dirtier stuff is road salt.
You say funny things sometimes. I suppose the guys a AB sat around watching coal getting shoveled out of the hoppers down in the Menonomee river valley while putting down a few Millers, quality control why bother bad train load just throw out this weeks production. It's not like pure graphite is a rare mineral. BTW the composition is graphite and ceramic filler to make a somewhat predictable bulk resistivity. Things are actually to good for the guitar effects guys these days, http://www.irctt.com/pdf_files/IBT.pdf.
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Except in the case of sea salt, where the dirty stuff is called gourmet sea salt.
Hi Guys,
I wonder how many of you have seen this you tube video from an ESS engineer
RMAF 11: Noise Shaping Sigma Delta Based Dacs, Martin Mallison, CTO, ESS Technology - YouTube
really interesting regarding subjective / objective observation discussion.
I wonder how many of you have seen this you tube video from an ESS engineer
RMAF 11: Noise Shaping Sigma Delta Based Dacs, Martin Mallison, CTO, ESS Technology - YouTube
really interesting regarding subjective / objective observation discussion.
Oh I am so emphatically with you on this. Let me read something! No matter how good the presenter, it just wastes so much time. One health letter person will send me these frantic appeals about something that the government doesn't want you to know yada yada. But it's only available as a video! I made the mistake of beginning to listen to her, on another topic, and she drones on portentously as slides are sequenced. I suspect it's a conscious attempt at what used to be quite the fad, neurolinguistic programming. I think it is completely insulting.
I'm listening to this now, and he's less tedious than many. It would however be extremely helpful if he would cite some references to these various "recent results", particularly the psychophysics.
I think I have all of ESS public app notes, white papers
all I can find is one graph suggesting the "bad competitor" DAC audio band noise floor rose ~ 10 dB from -117 dB to -106-7 dB as signal amplitude rose into the top -10 dB to 0 dB fs of the converter
using estimates of recording mic noise, home listening room noise floor, masking curves..
..I simply don't see where that (delta-sigma?) DAC's noise floor modulation is going to be audible with music played in the top 10 dB of the DAC, not with THX system sensitivity, or even 120 dB SPL peak system capability
all I can find is one graph suggesting the "bad competitor" DAC audio band noise floor rose ~ 10 dB from -117 dB to -106-7 dB as signal amplitude rose into the top -10 dB to 0 dB fs of the converter
using estimates of recording mic noise, home listening room noise floor, masking curves..
..I simply don't see where that (delta-sigma?) DAC's noise floor modulation is going to be audible with music played in the top 10 dB of the DAC, not with THX system sensitivity, or even 120 dB SPL peak system capability
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the ESS talk
I may have missed it but I never heard any description of the testing methodology, even the notion that it was double-blind or ought to be. There was the mention that some people in the company had been trained to better detect the supposed audible differences between their Hyperstream modulators and the more conventional 5th order sigma-delta ones.
He also mentioned Nature as a good thing to read for the psychophysics stuff, which is odd because I subscribe and don't recall anything in the recent period he mentions. But I may have missed it. He talks about being in the presence of a stationary stochastic process soundfield (without naming them thus) such as a waterfall's noise, as still permitting hearing changes in the soundfield (the example given of a tiger), clearly looking for a tie-in to evolutionary pressures to foster such acuity. He talks about little motors at the base of each hair in the cochlea as somehow vastly changing the supposed functionality of the ear.
He talks about some sort of perturbation of internal state variables with Hyperstream that somehow renders the conversion process to be less chaotic compared to sigma-delta, and explains that this eliminates noise modulation with signal level, and asserts that this is audible. He also mentioned that Matlab now fully captures the functionality of sigma-delta modulators, while (to him, happily) not yet Hyperstream.
Unfortunately I found the interesting bits to be fairly well-interspersed with tediously laborious constructions to avoid the use of maths. I did appreciate his candid admission that ESS doesn't reveal much about their products other than to core customers. as he said that competitors just wind up copying their stuff.
The presentation would have benefited immensely from a handout of references.
I may have missed it but I never heard any description of the testing methodology, even the notion that it was double-blind or ought to be. There was the mention that some people in the company had been trained to better detect the supposed audible differences between their Hyperstream modulators and the more conventional 5th order sigma-delta ones.
He also mentioned Nature as a good thing to read for the psychophysics stuff, which is odd because I subscribe and don't recall anything in the recent period he mentions. But I may have missed it. He talks about being in the presence of a stationary stochastic process soundfield (without naming them thus) such as a waterfall's noise, as still permitting hearing changes in the soundfield (the example given of a tiger), clearly looking for a tie-in to evolutionary pressures to foster such acuity. He talks about little motors at the base of each hair in the cochlea as somehow vastly changing the supposed functionality of the ear.
He talks about some sort of perturbation of internal state variables with Hyperstream that somehow renders the conversion process to be less chaotic compared to sigma-delta, and explains that this eliminates noise modulation with signal level, and asserts that this is audible. He also mentioned that Matlab now fully captures the functionality of sigma-delta modulators, while (to him, happily) not yet Hyperstream.
Unfortunately I found the interesting bits to be fairly well-interspersed with tediously laborious constructions to avoid the use of maths. I did appreciate his candid admission that ESS doesn't reveal much about their products other than to core customers. as he said that competitors just wind up copying their stuff.
The presentation would have benefited immensely from a handout of references.
The process I am familiar with is that they make up their magic mix from high carbon content coal and fillers. It is ground to a very fine powder and then pressed into shape and finally encapsulated.
The resistors were then sorted for value and marked. As a result they did the 5% parts first and the ones that were off those values a bit more became 10% and the junk 20%.
Now if Allen Bradley did theirs differently you might just get a higher quality product. Oh wait they did have a higher quality product!
The part I find interesting is the the fans of carbon composition resistors seem to prefer the poorest performers. (As you cited.)
On your samples of carbon composition that are off value, why don't you try a low slow bake to see if they come back on value.
ES
I guess we have no disagreement. I made trouble for myself in not distinguishing time period of manufacture. I've met pedal effects guys that sought WWII vintage resistors for their gadjets. Here's more of the quote, this guy actually makes solid engineering sense.
Slightly On-topic this time:
Went to the IBC convention in Amsterdam today, you know, the broadcaster's version of an AES convention (only an order of magnitude larger).
A guy offered air coils for transmitters: half-inch silver coated copper tube, maybe 10 windings, a foot-and-a-half long, a foot diameter. JC eat your heart out
jan
Went to the IBC convention in Amsterdam today, you know, the broadcaster's version of an AES convention (only an order of magnitude larger).
A guy offered air coils for transmitters: half-inch silver coated copper tube, maybe 10 windings, a foot-and-a-half long, a foot diameter. JC eat your heart out
jan
I knew I should have included the
Actually, I am relaxed, and have been for 12 years now. My point is, my life does not depend on what you believe. I do not worry.. So, I'm way ahead of you in the relaxation thing.
I would have to assume that there might be some kind of nonlinearity in the materials, but haven't a clue what. I do know that back in the mid 80's I ran two wafer probe stations for die testing and binning.
When I used a very tiny sharp probe on the emitter, if the test required anywhere from 100 milliamps to one amp, there would be a distinct non linear contact problem. When the problem caused devices to fail Hfe or VceSat, I'd add another probe for the voltage pickup, the current drive would handle the voltage error.
That's the best I got..
We have it worse here. Lead free solder is deemed hazardous waste, silver..
Doesn't sound useless to me.
If it's shiny that is required, then one should just get a solder pot, fill it with 63/37, and dip it to get it very shiny.
If straight is needed, take a piece of flat, like a piece of granite countertop scrap or 2 half inch thick pieces of bar stock 2 inches wide with smooth flat surfaces, and roll the lead between them. The lead will become incredibly straight. Scrape or brush first, dip using RMA, roll, then re-dip with R. You will get some real eye candy.
If the part is current age and lead free, this has the added bonus of preventing whiskers down the road.
Slightly On-topic this time:
A guy offered air coils for transmitters: half-inch silver coated copper tube, maybe 10 windings, a foot-and-a-half long, a foot diameter. JC eat your heart out
jan
Talk about shiny surfaces.. Are you sure you didn't take a wrong turn and end up in the high end auto suspension parts aisle??
jn
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