I mean the difference between a resistor with the following attributes:
1/4 W, 1%, 50 PPM Vs 1/2 W, 0.1%, 15 PPM
I suppose it could make a difference in the output stage, but not in the gain stage? Or they make a difference in any stages at all?
Or even exact same attributes between the following brands:
KOA, Vishay and Yageo
Yageo can cost half the price over almost any other brand, except Royal Ohm for what I've seen so far.
Koa Resistors cost about 0.21 USD, but Yageo pushes the limit to 0.10 USD on Mouser. One cannot stop to think how cheap can they be and how reliable could they not be for that price.
Are Chinese / Taiwanese components with the same specs, as good as Koa or Vishay?
Are Koa or any other Japanese or American components really manufactured in their countries? Or they have factories in China as well?
What are your thoughts about this?
1/4 W, 1%, 50 PPM Vs 1/2 W, 0.1%, 15 PPM
I suppose it could make a difference in the output stage, but not in the gain stage? Or they make a difference in any stages at all?
Or even exact same attributes between the following brands:
KOA, Vishay and Yageo
Yageo can cost half the price over almost any other brand, except Royal Ohm for what I've seen so far.
Koa Resistors cost about 0.21 USD, but Yageo pushes the limit to 0.10 USD on Mouser. One cannot stop to think how cheap can they be and how reliable could they not be for that price.
Are Chinese / Taiwanese components with the same specs, as good as Koa or Vishay?
Are Koa or any other Japanese or American components really manufactured in their countries? Or they have factories in China as well?
What are your thoughts about this?
If you're paralleling gain stages - for example when chipamps are used in parallel to boost output current - then there's a world of difference between 1% and 0.1% gain setting resistors in terms of cross-currents. But that is something of a niche application.
It depends a lot on where they are used.
If you are building a precision attenuator, 0.1% may be called for.
If you use them to set a current source to 'about 2mA', 1% is already overkill.
Jan
If you are building a precision attenuator, 0.1% may be called for.
If you use them to set a current source to 'about 2mA', 1% is already overkill.
Jan
So for an audio amplifier, overall, 1% 50PPM would be enough?
And about the brands? Are KOA worth the price?
And about the brands? Are KOA worth the price?
If they are all metal film the quality is a non-issue (but avoid unbranded, go for something sold by a mainstream electronics distributer).
You must ensure the device meets the requirements upon it - if the circuit says 0.1%, you need 0.1% or better, if it says 5%, either 5%, 1% or 0.1% are fine (but probably more costly than needed). If 0.5W dissipation is specified, a quarter watt resistor is not going to work. but 1W is fine (if it fits).
Metal film resistors are the most perfect components of the passives, very very linear, very stable. You'd struggle to notice a difference in behaviour with a full lab of test equipment unless one was damaged, say a loose end-cap or cracked substrate. I suppose you could vary the temperature and measure the tempco - 0.1% resistors usually have smaller tempco's than 1% resistors.
You must ensure the device meets the requirements upon it - if the circuit says 0.1%, you need 0.1% or better, if it says 5%, either 5%, 1% or 0.1% are fine (but probably more costly than needed). If 0.5W dissipation is specified, a quarter watt resistor is not going to work. but 1W is fine (if it fits).
Metal film resistors are the most perfect components of the passives, very very linear, very stable. You'd struggle to notice a difference in behaviour with a full lab of test equipment unless one was damaged, say a loose end-cap or cracked substrate. I suppose you could vary the temperature and measure the tempco - 0.1% resistors usually have smaller tempco's than 1% resistors.
