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Top resistors

Many threads with opinions on boutique coupling capacitors, but very little consolidated information on the sonics of resistors. Anyone care to share their thoughts on the attributes of their favorite brands & types for specific tube and SS applications? How much of a difference does a good resistor make?

My interest in the topic increased after recently installing the latest Texas Components nude Vishay TX2575 in several SS and tube phono & LS components. This was a proverbial "Ah-ha" moment-- a stray resistor dropped into signal path here or there, surprising with an improvement that equalled or surpassed the impact of a switch to a top coupling cap like V-Cap or Mundorf.
dgarretson
ptmconsulting
1,000 posts
 
If you want a little warmth added to that transparency you could add a Riken Ohm in series, following the Vishay. Of course you would have to use different values to sum to the value you want.

I did something similar in my Hagerman step up. There are 2 resistors in the signal path. The first one I use the naked Vishay, but using that in both spots was just too revealing. Adding the Riken Ohm carbon to the second spot was (as the baby bear says) just right. I then used the leftover Vishay for cartridge loading, with another improvement.
vit58
3 posts
 
Can Anyone help me identify the wattage of Caddock MDN0178 11.75ohm, 2% resistors used in the tweeter section of Wilson Audio Sophia 3?
I'd like to change it for an 8ohm resistor but don't know the required power capacity.
pbnaudio's avatar
pbnaudio
1,613 posts
 
Look here Caddock

Depending on where in the crossover the resistor is inserted changing value is not recommended as the components values before the resistor are chosen seeing a certain load. Changing the resistor values will therefore change the filters transfer function i.e the crossover point of the tweeter.

However if the resistor is meant to be changed by the end user then on your question about power handling of the resistor in a tweeter crossover anything above 15-20W should work just fine, if you want to spend the $ go for the Caddock MP9100 they are available at Mouser MP9100 8 Ohm
vit58
3 posts
 
Thanks a lot!
Actually the resistors are outside the crossover system, so it shouldn't change the crossover point. But they do act as a kind of fuse, whereby upon certain critical power load they will open saving the tweeter from injury. Thats why I was asking about its power handling capacity. I understand that if the power rating is too high, they won't do their job as fuses, right?
pbnaudio's avatar
pbnaudio
1,613 posts
 
I do not see a Caddock MDN series of resistors listed anywhere so it would be hard to identify its wattage.

As far as using a resistor as a fuse, I've never heard of such thing and would consider it sub par engineering at best, probably not what one should expect form the folks at Wilson.

I would not worry too much about the fusing issue and just use the best resistor I could find, the Caddock MP9100 certainly being one of them.

Good Listening

Peter
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