Sound of potentiometer materials?

[john12ax7]

problems with too small smd resistors is pretty well known... this thread is about pot resistance element media...

This thread has veered enough I don't see why SMT would be off limits. It's not just about size, a bunch of 0805 from different manufacturers will measure and sound different.

For pots in particular, and components in general, differences are easily audible in high impedance, high voltage applications, like guitar amps. Less so, but still sometimes exist in low voltage, low impedance

 

[Newmarket]

This thread has veered enough I don't see why SMT would be off limits. It's not just about size, a bunch of 0805 from different manufacturers will measure and sound different.

For pots in particular, and components in general, differences are easily audible in high impedance, high voltage applications, like guitar amps. Less so, but still sometimes exist in low voltage, low impedance

Not disputing that. I recall reputable mixing desk companies talking about audible problems with SMT back in the 90s.
But what type of resistors are you talking about here. Serious applications will be be MELF or Thin Film chip types.

 

[john12ax7]

But what type of resistors are you talking about here. Serious applications will be be MELF or Thin Film chip types.

I agree. But doesn't that just show materials matter? Thin film is generally better than thick film. Bulk metal foil is better still. It becomes a question of what cost and performance is acceptable and very application specific.

You can see differences even in the same material in the same package. The standard 1/4w metal film resistor can measure and perform different among different manufacturers.

 

[JohnRoberts]

There is a tendency in audiophoolery screeds to take some small real world physical effect, and extrapolate out to that making night and day differences. I used to get into interesting debates with a senior transducer engineer while working at Peavey. He was our resident "golden ear" and I tried to use him productively*** on projects when I could. Sometimes he would fixate on something like atomic level behavior inside components and attempt to extrapolate that out to bulk phenomenon. What made our discussions interesting was that he is a degreed EE and has even been published in the AES journal once or twice.

JR

*** my favorite project with him was a small GP plug in crossover module used inside a power amp. He configured a staggered pole topology so that the critical midrange transition region was dominated by a one pole response for minimal phase funnies. It sounded remarkably good for a general purpose Xover.

 

[Tubetec]

I remember those CS series amps with the transformer and x-over options on the back via plugin modules .

 

[JohnRoberts]

I remember those CS series amps with the transformer and x-over options on the back via plugin modules .

yup... the staggered pole crossover was a plug in module used in the later generation CS800s... FWIW the conventional topology adjustable crossover was the better seller for people who bought with their eyes, and not their ears.

JR

 

[Madman]

Their is a book that someone wrote that did spectral analysts of caps resistors, pots, etc. he said that 2nd harmonic content was very hi in resistors, and if used in a gain stage it is definitely a color.

Interesting, can you tell us the name of the book?

Douglas Self´s - Small Signal Design treated this thema only superficial.

 

[gyraf]

..it makes me feel slightly uncomfortable that we can have such a long thread on a subject like this. Think of what the guests may think, if they don't read the actual content...


..there: I said it..

/Jakob E.

 

[JohnRoberts]

..it makes me feel slightly uncomfortable that we can have such a long thread on a subject like this. Think of what the guests may think, if they don't read the actual content...

maybe they will think we are cooler than we are.

JR

..there: I said it..

/Jakob E.

 

[FIX]

I'm glad the days of listening to speaker wires all day at places like A&M are over...

Use common sense with speaker wires, as no bad speaker wire ever ruined a hit song, as much as a hit song was never because of a piece of wire...

BUT, differences in small parts can add up if used in situations where they are the dominate part in a gain stage that would amplify the parts characteristics. Like carbon resistors at the input gain stage of a discrete op-amp. Or not using a NPO cap in the feedback path of a gain stage. The size of the output caps matters... And sometimes bypassing it with a u1 lowers the HF distortion, but for the most part thick film/thin film, etc has little effect on normal things. Just like low capacitance cable helps with mic lines but not so much line level...

It's usually the song that sells...

 

[soapfoot]

no bad speaker wire ever ruined a hit song, as much as a hit song was never because of a piece of wire...

While this is true, it's also true that primitive mechanical recording technology didn't stop the Louis Armstrong Hot Five and Hot Seven from making legendary, historically-significant recordings.

But few would argue that advancements in recording and playback since then haven't been valuable, and wonderful.

Even if I am not interested in chasing that last 0.0001%, I'm glad somebody is