Replacing MPR ballast resistors

The ballast resistors in my amp are JDC MPR 0.68ohm 5W ones. Its by a Chinese company. I am thinking of replacing it with better ones


Do you think Jantzen or Mundoff 5W metal oxide are a good choice?


Btw, if I use 10W ones instead of 5W, will there be any issues?? Just thinking that higher rating means the resistor won't be that hot.
 
Why change a perfectly good resistor?
I think your choice is over priced and no better that standard 10% wire wound or Metal Oxide resistors.
Heat it heat, no matter what power rating to go up to.


The only way to dissipate heat is with a larger surface area. If it still works as it should, why mess it up.
 
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Your boards are made for 5w size, 10w resistors will be twice the size, mostly length, and won't fit well.

WHat do you consider "better"? And what improvement do you expect? Of all the parts in the amp to replace, they are way down on my list, but that is just my opinion. I do agree with Jon, if the amp is working, why "fix" it?
 
The ballast resistors in my amp are JDC MPR 0.68ohm 5W ones. Its by a Chinese company. I am thinking of replacing it with better ones


Do you think Jantzen or Mundoff 5W metal oxide are a good choice?
Metal plate resistors are far superior to ruthenium oxide, that would be a downgrade. Basically metal film / foil / plate / wirewound are the top performers, metal oxide or carbon are worse.

Not that it matters much in that position as its inside the feedback loop.

But the first question are they genuine MPRs or fakes?
 
Metal plate resistors are far superior to ruthenium oxide, that would be a downgrade. Basically metal film / foil / plate / wirewound are the top performers, metal oxide or carbon are worse.

Not that it matters much in that position as its inside the feedback loop.

But the first question are they genuine MPRs or fakes?

Haha i am not sure. So i am going to get some good wirewound.
 
Your boards are made for 5w size, 10w resistors will be twice the size, mostly length, and won't fit well.

WHat do you consider "better"? And what improvement do you expect? Of all the parts in the amp to replace, they are way down on my list, but that is just my opinion. I do agree with Jon, if the amp is working, why "fix" it?

Thanks for the reply.

Regarding "better", I would say its brand and quality. Eg for capacitors, I am sure you would prefer brands like Nichicon, KEMET, Elna, Mundoff etc... compared to those like Capax, Teapo, Rscon...

For resistors, I believe brands like Vishay (esp. their Dale resistors) and ohmite etc.... would be preferred over chinese ones like JDC.

As for why "fix" it? ITs because I am recapping the amp. So, it would be easy to also replace the resistors at the same time.
 
You display a fascinating mix of faith and ignorance.

The ballast resistors in my amp are JDC MPR 0.68ohm 5W ones. Its by a Chinese company. I am thinking of replacing it with better ones
WHERE do you think the "better" ones are made?

Do you think Jantzen or Mundoff 5W metal oxide are a good choice?
No, as explained above they are worse than the original ones.
And what drov you to pick those brands?
eading too many "esoteric audio" pages?
That´s bad for your mental health.

Btw, if I use 10W ones instead of 5W, will there be any issues?? Just thinking that higher rating means the resistor won't be that hot.
Is there a thermal problem you are trying to solve?
Or simple thinking "higuer dissipation is better"?
In that case, whay not pick 100W ones?
20 times better than 5W
Why not 1000W ones?
Regarding "better", I would say its brand and quality.
For brand to mean something, it must *consistently* have shown much better performance along years.
Those you mention do not.
They do show hype, that´s for sure.

Eg for capacitors, I am sure you would prefer brands like Nichicon, KEMET, Elna, Mundoff etc... compared to those like Capax, Teapo, Rscon...
Hype means nothing in the real world, demonstrated higher performance does.
All ears waiting for solid proof for your claims, besides glowin reviews in mystery magazines.

For resistors, I believe brands like Vishay (esp. their Dale resistors) and ohmite etc.... would be preferred over chinese ones like JDC.
All are Chinese .
As for why "fix" it? ITs because I am recapping the amp. So, it would be easy to also replace the resistors at the same time.

Ok, replace them akll for famous grands.

Just remember to scratch the "Made in PRC" labels off.

Unless reseller (not manufacturer by any means) already did that for you 😉
 
JMFahey speaks for the majority of engineer base on choice of components.
If your pocket needs emptying, why not donate to a charity at home?
I await your request for advice on the many man made faults that will appear on this and other sites.


Nope, not falling into the trap....



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