[tomb]

PRP resistors have been touted as the audiophile version of V-D's. They also have a cool red color.

However after using them extensively, I got fed up with the wildly inconsistent epoxy coatings as compared to V-D's - different shapes, different sizes, easy to break, etc. I could also never tell a difference in sound quality from V-D's. In short: Unless you like the color (

) just use V-D's and stay away from PRP's.

 

[cobaltmute]

cMF50 Vishay Dale's supposedly fit in the Mini^3.

The I find interesting is the so many want the RN series Vishay over the CMf's but per the datasheets they are exactly the same.

 

[Uncle Erik]

Quote:

Originally Posted by sohels /img/forum/go_quote.gif I would think that the closer a resistor remains to its specified value over a reasonably wide range of temperature, the better it is. So if your build requires closely matched resistors, I guess you should invest in better resistors. I do not know much about specific brands though.

This. You want stability.

This is the reason why some people think their gear sounds better after warmup or having been left on 24/7. The heat makes the components drift in value which changes the sound. It's not so much "better" as the values have changed. Carbon comp resistors are the worst for this. Personally, I like the Vishay-Dale, too. They're stable, have tight tolerances and don't drift much.

I've used a few of the boutique resistors, but didn't think they were appreciably better than the Vishay-Dale, though being several times more expensive. Same with caps - I still like and use Orange Drops as often as possible. I've dropped several hundred of them into old radios and have never had a failure or problem.

 

[amb]

For the Mini³ , all the recommended resistors (Xicon MF-RC, Panasonic EROS2, Vishay-Dale RN50 or CMF50, Multicomp MF12) are 1% metal film with 50ppm thermal stability, so they are all good. Choose whichever that is most convenient for you.

 

[sputnik13]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Hold on, I must really be missing something. When did Rubycon start making resistors? Rubycon makes (or "made" but that's questionable always) Black Gate capacitors.

I wasn't implying that Rubycon makes resistors, I thought it'd be obvious if I said "Black Gate" that I'm referring to capacitors as it seems most people on here are knowledgeable about that.

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Although there is much debate about "audiophile" resistors, unless I want to really go down that road and use PRP or Holco resistors, I just stick with what I know works "best" or at least what is most recommended by those who know "best".

I don't know what works "best" and that's why I'm asking all these questions

I appreciate what you said about the Vishay Dale, but I think a few people overlooked that I mentioned RN50 (not RN55) is on the list of resistors recommended for the mini3 on amb.org's page (way below in the "resistor" section below the table of parts), which is why I was still asking for more clarification. I'm going to go read up on what "parasitic capacitance" is now

 

[sputnik13]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif This. You want stability. This is the reason why some people think their gear sounds better after warmup or having been left on 24/7. The heat makes the components drift in value which changes the sound. It's not so much "better" as the values have changed. Carbon comp resistors are the worst for this. Personally, I like the Vishay-Dale, too. They're stable, have tight tolerances and don't drift much. I've used a few of the boutique resistors, but didn't think they were appreciably better than the Vishay-Dale, though being several times more expensive. Same with caps - I still like and use Orange Drops as often as possible. I've dropped several hundred of them into old radios and have never had a failure or problem.

Thanks for that information, so I take it I need to look for stability more than anything else with resistors.

Quote:

Originally Posted by amb /img/forum/go_quote.gif For the Mini³ , all the recommended resistors (Xicon MF-RC, Panasonic EROS2, Vishay-Dale RN50 or CMF50, Multicomp MF12) are 1% metal film with 50ppm thermal stability, so they are all good. Choose whichever that is most convenient for you.

Ah, you mentioned something that I wasn't seeing anyone else mention, 50ppm thermal stability. I was wondering what that means. I'd looked for it online but haven't really found any information on what the number means, as in is lower better or is higher better. All the descriptions I'd found assume you already know what that means and just talk about what color band on the resistor implies what value.

Oh, thanks so much everyone for all your valuable feedback. I know on the one hand I could just build something with the parts recommended in the parts table on amb.org and most likely I'll be satisified with the sound, but I'm just interested in understanding as much as possible about everything that goes into the build and the reasons why. I do try to find information on my own but this is one subtlety that I've not found much information on so far, so thank you for entertaining my questions

 

[amb]

More precisely, it's a temperature coefficient expressed as ppm/°C (parts per million per degree Centigrade). 1ppm/°C is equivalent to 0.0001%/°C, so 50ppm/°C is 0.005%/°C. Over an operating temperature range of, say, 10-40°C, these resistors' resistance will not vary by more than 0.15%.

Not that the Mini³ circuit actually require that kind of thermal stability, but suffice to say that all the recommended resistors are excellent in this regard.

 

[dhp]

that whole resistor business sounds like BS to me if he's still using metal film resistors.

 

[Beefy]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif The I find interesting is the so many want the RN series Vishay over the CMf's but per the datasheets they are exactly the same.

I like the RN series because they are dirt cheap at Mouser

 

[mb3k]

Also, IIRC aren't the Vishay/Dale's rated higher than they're stated on the package? ie. a 1/4W Vishay/Dale RN can be placed in a 1/2W position with no worries.

 

[amb]

Quote:

Originally Posted by mb3k /img/forum/go_quote.gif Also, IIRC aren't the Vishay/Dale's rated higher than they're stated on the package? ie. a 1/4W Vishay/Dale RN can be placed in a 1/2W position with no worries.

Only because RN is "mil-spec", and subject to a more stringent rating requirement. The equivalent CMF resistors are rated double the power.

 

[fzman]

Some time ago, I built some passive line-level crossovers between preamp and amps so I could biamp. The crossover circuit uses two caps and two resistors, and is very much in the signal path. I tried a variety of caps, and settled on the auricap teflons. Resistors were also auditioned, including shinkoh tantalums, prps, vishays (black bodies from parts connexion), caddocks, rikennohm carbon films and finally the texas component baked vishay tx2532 (i think that's the number). there were definite sonic differences between them-- the texas components ones are the ones currently in there. are they 100 times better-- no! are they better-- yes! Would i replace 15 or so resistors in my signa22 psu with $8@ of these-- NO!

in the signal path, with a highly resolving system, I think these are worthwhile-- I've got some of the new z-foil variants on the way for my headphone amp (uses on two resistors per channel; feedback and input).

we shall see.......

 

[BobMcN]

The right resistor in the right spot can make as much difference as the right capacitor in the right spot. But not all caps nor all resistors need to be "audiophile" quality.

Bob

 

[Ratzilla]

Quote:

Originally Posted by BobMcN /img/forum/go_quote.gif The right resistor in the right spot can make as much difference as the right capacitor in the right spot. But not all caps nor all resistors need to be "audiophile" quality. Bob

I agree.

When resistors are made, they have a tolerance. For example, a 15k resistor can be anywhere from 14k-15k. The more expensive resistors will have a better chance of being close to 15k. If you get 10 5% resistors, you might get a few that are 14990 and a few that are 14500. If you get 10 1% resistors, you might get a few that are 14990 and a few that are 14850. In other words, they will be better but if you get lucky or manage to get some 5% resistors that are close to 15k, they will be as good as 1% resistors that are close to 15k

 

[guzzler]

Quote:

Originally Posted by Ratzilla /img/forum/go_quote.gif I agree. When resistors are made, they have a tolerance. For example, a 15k resistor can be anywhere from 14k-15k. The more expensive resistors will have a better chance of being close to 15k. If you get 10 5% resistors, you might get a few that are 14990 and a few that are 14500. If you get 10 1% resistors, you might get a few that are 14990 and a few that are 14850. In other words, they will be better but if you get lucky or manage to get some 5% resistors that are close to 15k, they will be as good as 1% resistors that are close to 15k

That's technically true, but not relevant at all. Firstly, 5% (generally carbon) resistors in small quantities are the same price as 1% metal film resistors. You can also pay vast sums for "audiophile approved" resistors that in terms of specs went out in the 1970s. Secondly, many resistor positions rely on ratios rather than absolute values. This is the case for all resistors in the mini3. So, it doesn't matter what the absolute value of a single resistor is, rather the ratio of two.

Some resistors will be low inductance, higher power, better tempco etc. These are picked for specific and demanding jobs, not those encountered at very low powers. In general, I would doubt in such a simple design you will hear any difference between reasonable quality metal film resistors and things much more expensive. If you don't mind paying a extra pound or two, go for it, it won't do any damage, but you won't miss out on anything if you don't.