Free resistors vs. good resistors?

OK,
Time for my weekly subjective question...

I work at a place where I can get all the carbon film resistors I need-I can go through as many as I need to get matched pairs, etc. It is free. These are the newer ones that look like the metal film ones (I thought they were metal film for a long time-till I saw the bags they came in.)

People say that the carbon ones add noise to a circuit. To buy metal films, They end up costing about $1.20 for ten 1% 1/2 watt resistors (Mouser). If I'm lucky, I can get two or three pairs of matched resistors from those 10.

Subjective question:
As a poor college student-still concerned with achieving good quality components-should I be buying resistors, or using the free ones?

Joel

go for the free ones! i doubt you will notice that much noise. carbon films are much better than they used to be and much much better than carbon comps.. how much older gear do you see with fancy 1% metal films in them?

It's hard to beat free, man. Noise is subjective. Sure it's there, but does it bother you? I can listen to old records all day, and if I really pay attention, sure I hear the noise floor, but I don't mind, it doesn't stop me from listening to it. =)

ju

I've been all about analog these days. Noise floor bothers me much less that over-bright high-end.

This is making me feel much better, as I have a G9, and two 1176's on the bench being built-and I didn't even realize they were with the carbon resistors!

Joel

I build with carbon film all the time.

The noise is not what you might think it is from reading on the web. This is why you got to test and build.

FWIW look at the section in the AOE about resistors the noise stuff with carbon and metal film overlap, Some carbon film are less noise than some metal film

Carbon films are great resistors, generally apreciated by audiophiles and audiofools. Specs are just a little bit noisier than metal film ones... Carbon COMPOSITION are the ones really noisy, but can generate nice harmonic products when used as plate resistors in tube circuits.

That said, V76 is a very quiet amp, with all carbon composition resistors. So is the Langevin AM16. Again, all carbon composition and very quiet amp.

Maybe with carbon films, you get the best of both worlds, but I never did resistor AB tests. No way to do that now. Maybe in the future.

I would get all the lot, if this is for free...

How much do the normal 5% metal films cost? I pay about 2 cents each for those (Philips SFR25 in my case).

Best regards,

Mikkel C. Simonsen

Well, for some reasong, I can't fing 5% on Mouser or Digikey. The 1% are $.12 each.

Joel

Raf, the original V76 used Roderstein or whatever they are called.
Not carbon comp. I measured the values in an old 76 and they were within 1% !

However, I used carbon comp in my V76 and it is extremely quiet.

WOW! Always thought they used carbon comp back then...

[quote author="CJ"]Raf, the original V76 used Roderstein or whatever they are called. [/quote]
Did they use the large(ish) dark-red ones? The ones I have are all marked 5%, and measure within 1%...

Best regards,

Mikkel C. Simonsen

ok, from Ollie:


"The resistors are Rosenthal metal oxide.... relabeled for the different companies; grey Telefunken, red TAB and Neumann and green Siemens."

MCS, the ones I saw were long skiny types.

I scored a whole bunch of the big ones at the surplus not long ago.

Raf, you have an email where I can reach you?
PM me.
Thanks!

These are the resistors I'm talking about:



The actual colour is dark red, and they are 1W, 1/2W and 1/4W sizes. I know they're German, but I don't know who made them. I've seen them in a lot of the good equipment from the sixties...

Best regards,

Mikkel C. Simonsen

> end up costing about $1.20 for ten 1% 1/2 watt resistors

Oh, whine, moan.

Decades ago I also paid $0.12 each (actually 2/$0.25) for resistors. Back when gasoline was $0.33/gallon and smokes were $0.50 per pack. And what I got was 1/2W 10%... none of this 1% frilly-stuff. And carbon-comp: we knew it was imperfect but there was nothing wrong with it in 99% of audio uses. Wire-wound existed in precision work but not DIY. Metal film was exotic stuff. Carbon-film hadn't been invented.

Oh, whine, moan.

Click to expand...

Well PRR, all I can say is I can't afford to smoke or drink, and paying $50 for resistors if I don't have to isn't that exciting to me...

The tolerences are able to be more precise with the carbon film for me as I can go thru any number of them to get a good match.

but there was nothing wrong with it in 99% of audio uses

Click to expand...

So would you say to go for the free stuff then?

Joel

The best resistors ARE free resistors! :grin:

PRR, smokes cost about $0.50 a pack when I started smoking. Damn, it's probably time I thought about quitting.

Joel, I entered the words "carbon film" into Mouser's search engine and it returned pages of 5% resistors.

As others have mentioned, there's nothing wrong with carbon film. The reputation for noisy operation (deserved or not) belongs to carbon-comp.

In the old days, the best resistors you could buy were precision wirewounds. Nowadays, we have metal films, which are just slightly quieter than carbon film (but also less robust).

So take the damn free resistors already. :razz:

I think the carbon comps got noisy when they used 1/2 watt plate resistors to dissipate a 1/4 watt of dc plus the ac signals, which in theory should not add to the power as there is as much plus is there is minus.

Gerald Weber states in his amp books that using a 1 watt in place of the 1/2 watt plate resistors should keep things relatively quiet. Usually the comps get noisy after time, moisture change, etc.

Right on guys-thanks for all your replys!

Soldering away...

:guinness:

[quote author="NewYorkDave"]smokes cost about $0.50 a pack when I started smoking. Damn, it's probably time I thought about quitting.[/quote]

Sorry... Not trying to start an off-topic discussion, but that reminds me of a funny story I just have to tell you.

Around 1981, I was having dinner in Chinatown with some friends. I ran out of smokes, so I went to the front of the restaurant to buy a pack from the cigarette machine. (I smoked Lucky Strikes back then--no filters!). I couldn't believe it, the price was 90 cents! I was scandalized. I returned to the table, told my friends of the price-gouging, and exclaimed, "That does it! When they go up to a dollar a pack, I'm quitting!"

:wink:

[quote author="NewYorkDave"]probably time I thought about quitting.[/quote]

Maybe we should start a smoking discussion over at the brewery...

In any case: I got married a year ago (this friday, btw :thumb and decided to quit smoking. I haven't touched a cigarette since, but I've gained a few pounds... fifty of them!

Smoking's a drag (heh!), but quitting can be just as bad. :green:

Peace,
Al.