Replace resistor by low-inductance resistor - Is it audible?

[JimmyBuckets]

Famously and humiliatingly wrong.

It says its a theory, so yes, quite possibly it could be wrong. Humiliatingly? Not sure.

 

[SIY]

It says its a theory, so yes, quite possibly it could be wrong. Humiliatingly? Not sure.

The basic mistakes wouldn’t be made by a physics grad student, much less a tenured professor.

 

[egellings]

The high-ish output impedance of the tube amp allows the back EMF from the speaker to push its output voltage terminals around a bit. A S.S. amp with milliohms of Zo will not allow that.

 

[JimmyBuckets]

The basic mistakes wouldn’t be made by a physics grad student, much less a tenured professor.

So you are genius and he is an idiot...is that your point?

 

[SIY]

So you are genius and he is an idiot...is that your point?

Use the example of his hubris as a lesson.

 

[JimmyBuckets]

Use the example of his hubris as a lesson.

Great idea.

 

[Robeaver]

I was following another YouTube speaker upgrade video and those "dreaded" sand caste resistors were brought up again. Thankfully, for this thread, I was able to deprogram myself that such resistors were so horrific.

However, when I finish building those Klipsch RP600M crossovers that I purchased when I had my Klipsch speakers, you know I'll be making clarifications that the resistors utilized in the crossover were not sand caste resistors. Needless to say, I won't offer them for sale here on this forum.

Do you have a picture of it wired up? I just did the crossover and im confused

 

[egellings]

What is wrong with those 'cement boat' sand cast resistors anyway?

 

[Francis Vaughan]

What is wrong with those 'cement boat' sand cast resistors anyway?

Nothing intrinsic. They just look a bit cheap. What matters is the actual resistor inside. So long as it is properly wound in a non- inductive manner it is fine for audio. No different to an expensive metal case high power resistor.
You can make any design cheaply or with care and expense.

 

[DonH56]

I'd forgotten about that Stereophile paper... Talk about a misapplication of a whole lot of theory, and much of it irrelevant if not flat-out wrong at audio frequencies. I also remember when technical articles would appear in Audio, The Audio Amateur, Stereophile, and other mags -- don't see much if any of that anymore, alas. Of course some are better than others...

As for the big sand brick resistors, I have not thought about them in years. Back when I last considered them, the issues I had were they were inductive (coil of wire in a "sand brick" as said earlier), had high tempco (though you could find low-Tc versions if you looked really hard), and over time and high'ish temperature the "sand" or ceramic coating tended to dry out and flake away. Today you can find nice metal or thick film resistors that are much better.

 

[DualTriode]

What is the issue with spending a few dollars on a high quality Mills resistor for you crossover?

I will spend a few dollars more for better quality inductors and capacitors as well.

If you want the cheapest least precision parts go ahead on.

 

[solderdude]

There is a difference between buying better quality and venturing in the snake-oil pricing.
A $100.- resistor or capacitor is not much better than a $3.- quality part. The cheap $ 0.30 might not be worth the saving but for a company using thousands the difference between $ 0.30 and $ 3.- per component is a big difference.

 

[Francis Vaughan]

What is the issue with spending a few dollars on a high quality Mills resistor for you crossover?

Like these?

https://www.vishay.com/docs/31824/mrw.pdf

 

[kristiansen]

This is so great! Now we need to find out if metal oxide resistors really are quieter in a preamp circuit than carbon composition resistors.

A quick Google search '

• Resistor noise is made up of three main types: thermal, contact, and shot noise. ...
• Wirewound resistors are the quietest, having only thermal noise, followed by metal film, metal oxide, carbon film, and lastly, carbon composition."

Fits well with own experience , noise is Carbon Composition problem , but they have a really good sound at a cheap price ,here they really stand out, And you should preferably get hold of the NOS version.
If you are serious about your hi-fi, you should of course always use non-inductive components.

 

[solderdude]

Resistor noise is not an issue with speakers.
That is more of an issue in very low signal pre-amps.

 

[ctrl]

What is the issue with spending a few dollars on a high quality Mills resistor for you crossover?
I will spend a few dollars more for better quality inductors and capacitors as well.

There is nothing at all wrong with spending more for "better" quality.
For the tweeter crossover I like to use metal oxide resistors, but not because of the low inductance, but because of the low manufacturing tolerances.

The important thing is that in the frequency range up to 20kHz, at "normal" sound pressure levels, there is hardly any measurable difference/advantage between sandcast and low inductance resistors.

If someone says, take resistor A, it costs ten times as much as resistor B, but instead of +-10% tolerance it has only +-1% tolerance - no problem.
Whenever someone claims that this or that resistor "makes a huge acoustical difference", one should become cautious and ask for evidence in the form of measurements on real loudspeakers for the claim.

Because otherwise (somewhat exaggeratedly formulated) the layman gets the impression that he only has to replace enough components (capacitors, resistors, coils, binding posts, speaker cables) in a speaker to turn a $200 loudspeaker into a top speaker worth godzillions of dollars.

 

[SIY]

Fits well with own experience , noise is Carbon Compecites problem , but they have a really good sound at a cheap price ,here they really stand out, And you should preferably get hold of the NOS version.
If you are serious about your hi-fi, you should of course always use non-inductive components.

There's not much correct here. Metal film resistors are extremely cheap (1-2 cents in hundred-lots). "Really good sound" does not compute for resistors having higher noise, poorer stability, and high TCR and VCR. NOS is even sillier. The "non-inductive component" thing is meaningless out of context.

 

[kristiansen]

There's not much correct here. Metal film resistors are extremely cheap (1-2 cents in hundred-lots). "Really good sound" does not compute for resistors having higher noise, poorer stability, and high TCR and VCR. NOS is even sillier. The "non-inductive component" thing is meaningless out of context.

I am aware that what measures best and meets zero errors theory should also sound best in your book.

Maybe it's not like that, it's not my experience when listening it seems like a lot of what we measure does not always match what we hear and prefer. And not at least, what is the most lifelike sound.
Was hi-fi so simple that what measured Best also sounded best then hi-fi would only be made in a way as TV.

Perhaps the qualities of carbon composition are that they are non inductive and do not have a hot spot.
Perhaps also that more natural materials were used and the size of the component was not tried to be reduced as much as possible
But I do not know why they sound good and right

Unstable , noisy with poor tolerance spec and temperature stability, completely agree and they should of course not be used where this data is of crucial importance.

 

[SIY]

I am aware that what measures best and meets zero errors theory should also sound best in your book.

Maybe it's not like that, it's not my experience when listening it seems like a lot of what we measure does not always match what we hear and prefer. And not at least, what is the most lifelike sound.
Was hi-fi so simple that what measured Best also sounded best then hi-fi would only be made in a way as TV.

Perhaps the qualities of carbon composition are that they are non inductive and do not have a hot spot.
Perhaps also that more natural materials were used and the size of the component was not tried to be reduced as much as possible
But I do not know why they sound good and right

Unstable , noisy with poor tolerance spec and temperature stability, completely agree and they should of course not be used where this data is of crucial importance.

There is indeed a lot of unsupported nonsense surrounding components and no shortage of people happy to increase the supply of ignorance.

 

[617]

There is nothing at all wrong with spending more for "better" quality.
For the tweeter crossover I like to use metal oxide resistors, but not because of the low inductance, but because of the low manufacturing tolerances.

The important thing is that in the frequency range up to 20kHz, at "normal" sound pressure levels, there is hardly any measurable difference/advantage between sandcast and low inductance resistors.

If someone says, take resistor A, it costs ten times as much as resistor B, but instead of +-10% tolerance it has only +-1% tolerance - no problem.
Whenever someone claims that this or that resistor "makes a huge acoustical difference", one should become cautious and ask for evidence in the form of measurements on real loudspeakers for the claim.

Because otherwise (somewhat exaggeratedly formulated) the layman gets the impression that he only has to replace enough components (capacitors, resistors, coils, binding posts, speaker cables) in a speaker to turn a $200 loudspeaker into a top speaker worth godzillions of dollars.

Yes, and to add to this, many crossover simulation programs analyze the sensitivity of a component to the final sound. For some parts in a crossover, being off by even 30 percent is not a huge deal, but for other, using tighter tolerance parts makes a big difference. Using a 1% resistor as a tweeter pad is a good example of that; caps and inductors in LCR notches are another place where higher quality parts matter. Components for a high or low pass network are a bit less critical since they often are being combined with a bunch of other parts to create the right curve, along with the falling response of the driver itself.