Which resistor is better for a home audio application? I’m sure they sound the same, but one of them is probably constructed better. The green one is a few cents more but that could simply be because they’re less common. Tolerance is good enough for either.
I have had the white ceramic ones crack off pieces from the corners, and the leads are short. Green ones have longer leads and no ceramic to crack. But does the ceramic dissipate heat better? I can’t tell what the green coating is. Little worried it is like a paper wrapping that will start flaking apart in 10 years.
I have had the white ceramic ones crack off pieces from the corners, and the leads are short. Green ones have longer leads and no ceramic to crack. But does the ceramic dissipate heat better? I can’t tell what the green coating is. Little worried it is like a paper wrapping that will start flaking apart in 10 years.
FWIW the green one is as ceramic as can be: wire wound around a ceramic tube or cylinder, coated with a baked-on clay/ceramic paste.
And not sure it dissipates less, I find quite the contrary: its wire is outside, and covered in an paper thin ceramic layer, then exposed to free air, the rectangular one has the wire inside a thicker wall ceramic case which is sand filled, definitely higher Thermal resistance to ambient.
Of course, NO paper used in any.
And not sure it dissipates less, I find quite the contrary: its wire is outside, and covered in an paper thin ceramic layer, then exposed to free air, the rectangular one has the wire inside a thicker wall ceramic case which is sand filled, definitely higher Thermal resistance to ambient.
Of course, NO paper used in any.
The green ones have 1%, the white ones 2% tolerance - if that matters at all - considering the much wider tolerance of T/S parameters from real speakers. Normally such cement resistors come with 5% or 10%.
There are dozens of both kinds in the lab in which I work. If they have the right resistance, tolerance, and power rating, there is no difference of any consequence between the green and white ones.
As bucks bunny said, when I buy ones that I need to have tighter tolerance, they are more likely to turn out to be the green type. I couldn't care less about their appearance, though, only that they meet their electrical specs. And both kinds do.
Used properly, within its power rating, I have never seen any kind of resistor fail after ten years. Resistors may be the most reliable component used in electronics.
-Gnobuddy
As bucks bunny said, when I buy ones that I need to have tighter tolerance, they are more likely to turn out to be the green type. I couldn't care less about their appearance, though, only that they meet their electrical specs. And both kinds do.
Used properly, within its power rating, I have never seen any kind of resistor fail after ten years. Resistors may be the most reliable component used in electronics.
-Gnobuddy
Thanks! I have only ever used the white ones and never had any trouble with them other than chipping of some corners. I’m about to order a bunch and saw these green ones that I’d never seen before and wondered if they were better in some way. The cost difference isn’t enough to matter. I like the longer leads on the green. Maybe I’ll just buy some of both. They always get used eventually.
You jest, but you are not far off the truth. Far too many people have been trained to believe equally idiotic things.
In the documentary film "Holy Chicken", Morgan Spurlock talks with image consultants who work with the fast-food industry to create a "health halo" over the garbage they serve as food. The "health halo" concept is to get people to think they are getting something healthy, though the food is the same toxic stuff served for the last may decades, the same stuff that's led to the current world-wide epidemic of obesity, diabetes, heart disease, et cetera.
In the fast-food industry, the "health halo" is generated by things like using green paint in selected areas on the walls of the restaurant, putting pictures of leaves on the place-mats and posters, serving salads alongside the fat-and-preservative-filled burgers and fries, and, of course, advertising that talks about how "green" the restaurant, its food suppliers, and its business practices are. 🙄
The same concept - fool the customer into thinking the product they are buying is good for the planet - extends far beyond fast-food. It's not a coincidence that Nissan's flagship electric vehicle is called the "Leaf", for instance.
-Gnobuddy
In India:
Green is ordinary resistance wire wound around a ceramic tube, and cemented in place.
White is a fusible resistor.
Use a higher rating if you are worried about heat dissipation.
Or:
Resistors with heat sinks...🙂
Green is ordinary resistance wire wound around a ceramic tube, and cemented in place.
White is a fusible resistor.
Use a higher rating if you are worried about heat dissipation.
Or:
Resistors with heat sinks...🙂
...you inow the story of a resistor who was living in a sealed tower and moved for an open structure without its white suit...et voilà...he gets mouldy...
I am crying guys...your fault. Never show pictures like that!
I am crying guys...your fault. Never show pictures like that!
My experience with testing power amplifiers and using these as dummy load resistors has shown that wirewound (white, green, gold anodized etc) all generate a significant amount of distortion (1% or more THD vs 0.0007% THD for metal thin film) as the power increases. Not sure if this affects speaker distortion but the lowest distortion resistors are metal thin film. However, they are hard to find in 10W sizes. You could parallel or series 3 or more 3W thin film ones to do the trick.
Having said this, in the interest of cost and convenience, I tend to use the 2% 10W white ones and 1% 10W green ones for speaker builds. For very special speakers, and for the critical padding resistor of a tweeter, I’ll use a high quality resistor like a Mills or a bunch of paralleled metal thin film ones.
Having said this, in the interest of cost and convenience, I tend to use the 2% 10W white ones and 1% 10W green ones for speaker builds. For very special speakers, and for the critical padding resistor of a tweeter, I’ll use a high quality resistor like a Mills or a bunch of paralleled metal thin film ones.
Harmonic distortion of that nature and low order isn't going to be a problem for speakers. Not to mention that resistors aren't used quite that way in a crossover.
It's the higher order distortions that amps can produce, and the unfortunate general adoption of total harmonic distortion as a metric that has people giving undue concern to more simple distortions like this.
It's the higher order distortions that amps can produce, and the unfortunate general adoption of total harmonic distortion as a metric that has people giving undue concern to more simple distortions like this.
With wirewound dummies I measure SINADs in the ballpark of 95~100dB with my TPA3251 RefPCB. So I cannot agree with your statement that wirewounds spoil THD numbers. Maybe you experienced some contact problems?
What brand and model wirewound? Mine were the speaker crossover ones. I also tried those huge green 100W “rheostat” style ones. Those were particularly bad. It maybe the type of contact resistance between the winding and the leads.
I think they are Vitrohm, but never cared. May check tomorrow
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I like the "PowerBook" idea. Maybe it is name brand wirewound gold anodized ones that make a difference.
If the green type's former is a tube, then it may help the resistor to lose heat more easily, as air can flow through the inside.
Why not double the Z value and use both in // if it is in front of a mid unit for instance ? But the cooling behavior, doubling the resistor wires may help at seing the wires diameter, no ? Of course we also understand the resistor purpose is indeed to avoid current to flow by disapating it into heat...