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Any scope photos of different resistors...

207.62.246.184

Posted on December 18, 2014 at 14:22:28
to show a skeptic that resistors at least may sound different. I know there are other measurements but he seems to revere the scope. For caps there is a treatis by Conrad Hoffman titled, Measured Differences Between Capacitors for Audio Applications with scope photos. Yea, all caps and all resistors sound the same. Don't know why I bother anymore. Thanks, Tweaker

 

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RE: Any scope photos of different resistors..., posted on March 17, 2018 at 09:42:44
More than three years after your question, apparently the answer (here) is "no".

 

RE: Any scope photos of different resistors..., posted on July 30, 2015 at 05:24:46
Posts: 516
Location: Upstate NY
Joined: September 3, 2007
Though I lurk here every now and then, I rarely post, as my beliefs and philosophies really don't go with the mainstream here. I can measure differences between just about anything, including resistors, but in general I rarely hear the subtle differences others claim. Usually, the more I refine the listening tests, the less difference I can hear. I've been down the interconnect and tweak rabbit hole plenty of times and still only partially understand all the biases that can be present, but I'm as subject to them as anybody. Thus, I don't make claims about what's real and what isn't.

It's interesting that Audio Precision has some notes where they found the expensive metal foil resistors have unexpected modulation distortion, and regular metal films are to be preferred! Nobody wants to hear that, since $$ resistors must be better. I use metal foils in DC metrology equipment, but not my audio stuff.

I recently built the "JCan" noise test fixture for resistors. It's interesting to note that excess noise is current dependent, and resistors with near zero current all generate about the same noise. It's even more interesting how incredibly bad carbon track pots are, compared to even carbon comp resistors. Metal film stepped attenuators for me any day of the week.

There may be other resistive effects beyond the usual tempco, stray L or C and voltage dependence, but all of it is incredibly small. There's probably nothing I can show you on a scope that's very meaningful. It would tend to be more tables of numbers and statistics!

A couple things I've come across are that thick film SMT resistors can be very noisy and that some MOX resistors have a surprisingly high voltage coefficient. Not all, so testing is the only way to know.

Conrad H.

 

RE: Any scope photos of different resistors..., posted on December 26, 2014 at 07:45:15
rick_m
Audiophile

Posts: 6230
Location: Oregon
Joined: August 11, 2005
Well, I don't have any pictures for but have experienced all sorts of resistor issues over the decades. Mostly the issue is excess noise but microphonics happen also. Carbon composition resistors are the worst things going because they are both noisy and microphonic. Metal films are usually the best. One way to think about carbon resistors is to consider telephone "transmitters": the thing you speak into. Essentually the active piece is a carbon resistor.

Maybe your friend should read a little rather than just looking at the pictures?

Rick

 

RE: Any scope photos of different resistors..., posted on February 1, 2015 at 13:33:52
Ugly
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Posts: 2912
Location: Des Moines, WA
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Hello Rick. Do you happen to know ofa sources describing excess noise in detail? I seem to recall that excess noise is voltage dependent but at line levels probably insignificant whereas at speaker signal levels perhaps a factor...Plenty out thee about shot, thermal, popcorn etc but not much describing "excess". Maybe I'm just using the wrong keyword in my searching.

 

RE: Any scope photos of different resistors..., posted on February 1, 2015 at 21:22:59
rick_m
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Location: Oregon
Joined: August 11, 2005
"Excess noise" is simply everything else beyond the (4kTRB)^1/2 thermal noise voltage.

It's just of a way of thinking about noise and keeping score. You can't avoid the thermal noise but you can work on the noise in "excess" of that such as the crud from micro-arcs in carbon comp. resistors.

Regards, Rick

 

RE: Any scope photos of different resistors..., posted on February 2, 2015 at 06:28:35
Ugly
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Posts: 2912
Location: Des Moines, WA
Joined: August 22, 2006
Ah. Your wording helps clear up a lot for me. It makes sense that micro arcing would be more pronounced with technologies using a depositing or sputtering process to form the conductive paths. I suppose it's difficult to really characterize this problem generally since it must have much to do with specific manufacturing process and materials.

Very interesting. Thanks for the explanation. I'd previously come across a fellows webpage briefly mentioning "contact" noise within conductors/ resistors etc. caused from micro arcing from voids and impurities. One co-worker/mentor of mine has used the term "Excess noise" and didn't explain it to me. Good to finally sort of tie these loose ends into a slightly neater bundle.

 

RE: Any scope photos of different resistors..., posted on September 9, 2017 at 10:36:19
pictureguy
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Why would micro arcing be more pronounced when the film is deposited by sputtering or perhaps evaporation?
Lots of variables in process design using those processes and enough equipment variation between manufacturers to keep things interesting.
I've used CHA evaporators and Varian sputtering systems.

Link provided so you can see a sputtering system for 6" silicon wafers.
Too much is never enough

 

RE: Any scope photos of different resistors..., posted on January 9, 2015 at 10:02:14
mcgjohn@yahoo.com
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Actually resistors do measure quite differently. Vishay has released several PDF files on this comparing the different types. carbon comps are usually noisier but do have a nice tonal quality to them. Carbon film are a bit quieter, next are metal film, then lower noise than metal film are wire wound. Metal foil are the quietest of the resistor types, but few if any mfgrs use all 100% metal foil resistors since the cost is so high.




 

RE: Any scope photos of different resistors..., posted on August 10, 2017 at 09:47:56
used-hifi
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Posts: 1100
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Metal foil resistors are not quieter then wire-wounds

I did this research a few years ago I wish I could post it.

and IMO metal foils sound bla, clear but don't pass the musical information in a dynamic way.


Lawrence

 

RE: Any scope photos of different resistors..., posted on January 9, 2015 at 11:26:29
rick_m
Audiophile

Posts: 6230
Location: Oregon
Joined: August 11, 2005
Well, we agree...

I didn't mention metal foil because I don't have any experience with them.

Resistors are like any other passive: despite what we call them they are all multi-pole, temperature (actually radiation in general), Vib. frequency and level sensitive networks.

But that makes their names ackward so we cut corners and just refer to them by their hopefully dominant characteristic, the item that we WISH was their only feature!

Actually once in a while you can cash-in on more than one like using WW power resistors as Q reduced RF chokes. But not very often...

Rick

 

An innocent question..., posted on December 19, 2014 at 03:46:20
What happens when a resistor that measures very good sounds worse than one that measures worse? You know, like amplifiers, cables, capacitors, speakers, stereo cartridges, things of that nature.

 

RE: An innocent question..., posted on February 1, 2015 at 13:40:40
Ugly
Audiophile

Posts: 2912
Location: Des Moines, WA
Joined: August 22, 2006
I'd conclude you have been measuring the wrong things if I trusted your judgement on the subjective evaluation..

 

RE: An innocent question..., posted on February 7, 2015 at 04:45:52
Ah, you're one of those measurements guys. Well, excuse me.

 

RE: An innocent question..., posted on February 10, 2015 at 20:04:49
Ugly
Audiophile

Posts: 2912
Location: Des Moines, WA
Joined: August 22, 2006
Did I get the right answer?

 

RE: An innocent question..., posted on February 24, 2015 at 04:12:41
What do you think? :-)

 

It ain't me..., posted on December 20, 2014 at 13:39:01
This is just a game to play with a total non audiophile objectivist. I only care what something sounds like to me. Sometimes technical info is usefull. Saw you on the tweaker's asylum, Geoff. How gos it? Who let you out of the cage??? Tweaker

 

RE: It ain't me..., posted on January 19, 2018 at 03:37:36
JURB
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"This is just a game to play with a total non audiophile objectivist. "

The only way you are going to show anything is to build a bridge and null out the signal. There is no other way to make a subtle difference visible, and that is if it is even possible then. We are talking nuances here that are practically impossible to measure even with ten grand worth of equipment.

I wonder maybe if a Wien bridge instrumentation oscillator and a spectrum analyser might show something. Perhaps if you have a whole distortion meter setup.

I have a pretty good one, an HP 339A. This has auto null and its own oscillator. The measurement floor is 0.0016 % which is low, bu it might not be low enough to show anything like you're trying to display.

Good luck, you'll need it.

 

RE: An innocent question..., posted on December 19, 2014 at 07:04:11
Tony Lauck
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Posts: 13629
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"What happens when a resistor that measures very good sounds worse than one that measures worse?"

It depends on who is judging. Some people prefer noise and distortion, thinking that it improves the sound. Since artificially induced noise and distortion are the norm in some musical genres, IMO people who listen mostly or only to those genres are not qualified to judge whether sound is "better" or "worse" as they lack a true reference. I listen to acoustic music, preferably recorded with a minimal number of microphones in a concert space and not a studio. I am not inclined to pay much attention to reports of how other musical genres sound "better" on particular equipment, as this is not relevant for my purposes.

If one concentrates on whether the sounds are "the same" or "different" then these questions of taste disappear.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

-1, posted on December 20, 2014 at 22:39:46
Awe-d-o-file
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While I like most of your posts this one sort of seems to say things I don't like. I never prefer noise or distortion in the recording process. That is completely different than the few types of "purposed" distortion I can tolerate in electric music. I listen to acoustic and electric music. I do like some preamp level distortion on electric guitar (except some tube amps) for instance but never at the power amp level or by recording at levels or in a way that would distort even acoustic instruments recorded via microphones.


I know the kind of "space" that can be created by using a mic to record sound in a "room". I've also heard plenty of recordings in all genres that have a large noise floor using only mics to record acoustic sources. I also know that some things recorded direct with no mic can sound good too. I have many 2 mic acoustic recordings and they vary widely in quality. Some are not so good and it has some to do with the room and improper mic placement. Studios in my opinion are like restaurants in that they vary in quality some are good and some are sterile.


You just can't generalize on this. You can say what music you prefer as you did. And that's it. But how you went from the OP's topic of how one might determine if electric components used in reproduction of sound may differ to passing judgment on what music or recordings people use is totally beyond me and a little snooty as I see it.

His question had nothing to do with music or different types of recordings.


E
T

ET

"If at first you don't succeed, keep on sucking till you do suck seed" - Curly Howard 1936

 

RE: -1, posted on January 19, 2018 at 03:43:03
JURB
Audiophile

Posts: 2056
Location: North Ohio
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"I never prefer noise or distortion in the recording process. "

You might want to look up something called dither.

Dither is noise added to a digital recording when making copies to get the threshold up to one bit of information so the quantization is abated. It started with the original CDs, people said the DDD ones sounded funny, grainy or something. Dither took care of that.

The dither is exactly at the level at which it will not be reproduced, just brings up the floor to the minimum quantization level. On AAD or ADD recordings the slight noise was already there and no dither was necessary. In fact I suspect the quantization process removed some of that noise losslessly.

 

RE: -1, posted on February 16, 2015 at 11:47:48
Tony Lauck
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Posts: 13629
Location: Vermont
Joined: November 12, 2007
I said "some people" prefer certain distortions. I guess you are not one of them. :-)

As to an electric guitar, in this case the distortion is part of the instrument construction and the artistry of the musician. All musical instruments have distortion. For example, my wife's grand piano would clearly distort if one attempted to play too loudly and the keyboard would make annoying noise if one banged on the keys.

The type of distortion that I really object to comes from distortion that affects the sound of all the instruments. If this is added to the recording (an extreme example is clipping distortion) one will get intermodulation from the separate instruments and their individual realism will disappear. In some cases, BTW, this can happen in a live acoustic concert setting turing very loud passages. In this case it is one's ears that are distorting. Again, this may be intentional on the part of the composer or performers, but I prefer to sit back far enough so that this effect does not happen often.

All the different causes of distortion have their unique effects on the sound that we perceive, as will be appreciated by experienced critical listeners.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

+1, posted on December 19, 2014 at 14:05:11
Posts: 2762
Location: Orange Co., Ca
Joined: September 19, 2001
I agree.

People think that 'preferable' must also be 'better'. If something sounds preferable that must because either:
1. It conveys some quintessence of the music that another system cannot
2. It adds something that makes the sound more pleasing.

IMHO #2 is by far the most likely reason that many prefer vinyl and tubes. Preferable is correct for that person (but not objectively better)

To answer Geoff's comment about 1970's SS amps - those generated a lot of distortion too but dynamically, though they tested great on sine waves. It was a rather unfortunate time, especially as dynamic limiting in feedback systems had been analyzed for decades before that time.

Regards
13DoW

 

RE: An innocent question..., posted on December 19, 2014 at 07:40:23
That was exactly the same argument that those horrible sounding solid state amps made back in the seventies and eighties, that if you preferred the better sounding Tube Amos you must like distortion. That's the ugly sister of the argument, speakers have 4% THD so distortion figures for amps, preamps, etc. don't matter.

 

RE: An innocent question..., posted on December 19, 2014 at 09:45:56
Tony Lauck
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Posts: 13629
Location: Vermont
Joined: November 12, 2007
Not my experience at all. I found those "horrible" SS amps that I heard to be ugly compared to tube amps. Later, there were good SS amps. This is with acoustic music, which is just about the only kind of music that I listen to.

Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

 

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