Metal film resistors or carbon film in a tube amp?

[jh6you]

This is another copy from http://www.nmr.mgh.harvard.edu/~rees...les_v01_4.html



JH

..........
I also changed the Radio Shack carbon films on the 5842 grid and cathode resistors
with half watt carbon comps and immediately noticed more tonal color and less bite.
I'm beginning to use more and more of them for what they can bring to the sound.
The only place I've had a problem with them is using them as plate resistors in the 5687
linestage. I had a pair make strange noises there, otherwise no problems and cheap
too (Mouser, 28 cents each). Those were NOS carbon comp resistors.
..........

[peranders]

Originally posted by Fred Dieckmann
ABSOLUTELY CLUELESS! Anybody that thinks that this is advice deserves to follow it. I am embarassed to read such nonsense which flys in the face of common sense and reality. I think that the reply must have been posted as a joke since nobody could be so misinformed. It is post like this make me wish I could put people in the sin bin.

Fred, I have never heard you missioning for metal film. Also, Fred, sending me to sin bin just for expressing a view???

If I had built a tube amp today I had never consider to choose carbon resistors if there have been an alternative.

Fred since you are enlighted (previous actions), what is your opinion really? Sometimes it seems that you have opinions opposite of mine.

My opinion is that metal film is the best "normal" resistor type today for normal applications. They are also really cheap.

[peranders]

Originally posted by jh6you
I use 2W 750V 1% or 1W 500V 1% metal films. The 2W units have the lowest noise, but take up more space. If you can't get a great tone out of an amplifier using metal films, you are doing something wrong. The only thing you have to lose is the noise.

Do you really use metal FILM? Not metal OXODE?

[Carl Ekblom]

I usually try to avoid cheap metalfilm resistors at critical positions as I think they can make an amplifier sounding too bright. Some carbon film typs are much better.

But there are really good metalfilm types around. See the link http://www.borbelyaudio.com/index8.htm where Mr Borbely discuss the effects of different typs. His opinions are very much in the line what I have found.

Carl

[jh6you]

Originally posted by peranders
Do you really use metal FILM? Not metal OXODE?

Please take it easy and read my post again. The comment was not mine. It was a copy from the indicated website.

Anyhow, I have no more tube amps.
For my current diy mosfet amps, I use metal film of 0.5W and wirewound power resistors of inductunce-free construction.

JH

[Fred Dieckmann]

Yes, and they are based on building, modifying, and listening to high end audio equipment for over 20 years. I try not to post opinions with which I do not have the personal experience with the subject at hand. I have plenty over expierience with tube amps and exotic resistors. I have no idea where your opinions come from.............. They often don't seem to be based on knowledge or experience, which leaves me to wonder where they do come from.

[G]

Guys, I just wanted to have stable biasing on my tubes. I have always heard that carbon film has a warmer sound. This I can neither prove or disprove. I think that I am going to use the BC components 2 watt metal film(DigiKey section F) for biasing and carbon films for signal. I will let you know what I think. I'm still waiting for a choke that I ordered so it could be a couple of weeks before I have anything to write about. I will alternate between MF and CF and let you know my impressions.

G

[Elso Kwak]

Hi ,
Please see Application Note 42 by Linear Technology, <B>Appendix A.</B>
It contains a overview of common resistor types: Carbon composition (also known as Allen Bradley), carbon film, metal film, and bulk metal film, wirewound etc.
http://www.linear.com/pdf/an42.pdf

[G]

It also says nothing about how they sound in a tube circuit. But thanks for the link Fred.

G

[Joel]

Originally posted by dhaen
Mmm, I'll have to ask Joel which make "sound" better

I get all my resistors custom made now. They're made of the carbonized finger bones of red-tailed squirrel lemurs, from southeast asia. They cost me $800 each, but the high end is so silky and smooth. Nothing else can compare.