Tyco Neohm resistors any good?

[PauloPT]

Hi!

I was wondering if anyone has experience with Tyco/Neohm metal film resistors. Are these good for audio?

Here's the datasheet:


Thanks.

[Damon Hill]

Tighter tolerances and lower temperature coefficients than the typical metal film resistors. I'd say these are pretty good, especially if you can get the lower Tc types.
Voltage coefficient is also significant, but rarely specified most of the time so I'm not sure how well this series compares to others.

[PauloPT]

Thanks, Damon Hill

Any clue if they are inductive?

[Damon Hill]

Not significantly; I think this concern is overblown for parts this small. Leads are copper, but the end caps may be ferrous.

Vishay bulk foil resistors are the very best, and very expensive...these Tycos will be much more cost-effective.

[PauloPT]

I don't know if they are inductive or capacitive or pure resistive but they sure are magnetic! I have some of these resistors and I tested them with a small magnet and they "glued" on it. Don't know if this has an effect on sound or not...

Vishay bulk foils are very expensive...

I'm thinking in these tycos or maybe Takman metal film. One other option might be Audio Note tantaluns but these are 1% 100ppm wich is worst than the tycos... I like these tycos because they have a nice datasheet but are they any good for audio? Any advice would be very welcome!

[Damon Hill]

I've never found specifications for the tantalum resistors; I thought they'd be tighter tolerance and better Tc.

In the objective sense, which is what I consider first, the Tycos are very good--better than any of the other parts mentioned except bulk foil, which are the very best of any resistor of its size and ratings.

Subjectively, some people prefer the sound of carbon resistors, which have poorer electrical specifications by a considerable margin. Carbon composition appear to be actively piezoelectric--very poor voltage coefficient--but again, some people prefer what they call a 'warm' and rich sound.

I actively search for bulk foil resistors but the best of that type, the Z-foils are outside my budget altogether--and I really don't like the construction of the 'naked' bulk foil types. So I can only use them very sparingly in what I think are the most critical locations, and use the best metal films in most other locations.

In non-audio applications, as long as tight values and low Tc aren't required, most any resistor type will work fine. Don't overlook wirewounds, some of them should be nearly as good as bulk foil if their Tc is very low. But they are not as common as they once were.

[Damon Hill]

Here's an opinion from an audio designer for high quality resistors which he likes to use:

Aria Audio

Resistors

And they're mostly expensive. I have to fall back on less esoteric metal film most of the time, and the main guideline is a very low Tc (which is what precision resistors require to remain precise!) and low voltage coefficient. 50 ppm is better, and 25 ppm is still affordable; bulk foil resistors can be as low as 0.05 ppm.

But I suspect that elusive voltage coefficient is more significant than most people realize.

[PauloPT]

I've never found specifications for the tantalum resistors; I thought they'd be tighter tolerance and better Tc.

Sorry, I meant the Takmans are 1% 100ppm. I don't know about the tantaluns, can't find any datasheet of them. I wonder if they are objectively as good as people believe...
I agree with you about lower TCR gives better, more transparent, sound but the Z-foils are to much expensive for me. I'd go with the Tycos but for signal path I'd like something better. Are the Takmans (even with worse TCR) or the Shinkoh a better choice?

[Damon Hill]

Let your budget be your guide. The Tycos seem like a better choice for the money given the known specifications. Shinkoh tantalums have a high audiophile reputation, but lacking hard information I've never used them (though I did buy a sample to see if I could estimate Tc--seemed no different from a good metal film).

[PauloPT]

though I did buy a sample to see if I could estimate Tc--seemed no different from a good metal film

What was the value you estimated?

I think your right. It's good advice. Theres only one thing now that bothers me: the ferromagnetic end caps. Many people around here don't like magnetic parts. Metal histeresys and current induced magnetic fields across the resistors. Should this be a concern? I mean, is it detrimental to sound quality or the effects are negligible?

Thank you for your good advice