SO, I got some 1W metal-film R's...and

[pula58]

My idea was to use 1W instead of 1/2W thinking that a larger resistor would have less noise (nosie in excess of 4KTR johnson noise). So, I ordered these:

http://www.mouser.com/Search/ProductDet ... PF1-F-1.5K

http://www.vishay.com/docs/31021/cpf.pdf


nd they are even smaller than the 1/2W Xicon metal-film R's I have been using.
So, I a wondering about any noise (hiss) advantage, in this case of going to the 1W R's that are phtically smaller than the 1/2W ones I was using before.

And,,man,,they look so small, I have an emotional block to using them! They look like 1/4W R's!

I am thinking I might like to find some nice 1W metal film R's that are larger than the ones I showed the link to (above).

Any good experiences with 1W metal film R's, some nice fat ones!?

Thanks!

P.

[jjman]

I have the 3watt version of those on the same spec sheet. They are smaller than old 1 watt carbon comps but not small enough to cause that "too small" feeling. They tested lower hiss for me compared to banded 3watt Vishays also available and also somewhat small.

[Cantplay]

Riken, if you can find them.

I've used 1W PRP resistors, low noise, long leads, and numericaly marked with value. They are also available and inexpensive.

I'm going to try AMRG on my next build.

John

[Prairie Dawg]

I use those small 2w Vishays from Mouser in Fender sockets all the time because they're easy to work with. Never had one fail yet.

[JazzGuitarGimp]

Resistors are definitely 'small' these days. But I would think that by going to metal film, the noise floor will be so much less than it was a few decades ago, when CC resistors were the norm for guitar amps, that you're going to be way ahead of the noise game, regardless of their size. (How's that for a run-on sentence?!) In a nutshell then: MF are known to be very low noise compared to CC. I think you'd be okay with what you've got.

[Gaz]

It's my understanding that if you have two resistors of the same type, the one that is physically larger will have less noise regardless of wattage.

[roberto]

Overall better efficiency in electronics led to lower mean temperatures on circuits, so smaller components can dissipate more heat (because the overall temperature is lower), and this make possible to over-rate the component's wattage of the same size?

I'm thinking also about some components that are under-rated on military specs.

[Structo]

Yeah, I made that same mistake before.
Ordered a bunch of Vishay 1w resistors and they were tiny.


Check out the CCF60 series from Vishay.

They are nice!

500v, 1% tolerance

http://www.mouser.com/Passive-Component ... 60&FS=True

[tele caster]

I used some of these cmf60. About the same size as 1/2 watt, but rated at 500v. Has anyone else tried these?

http://tubedepot.com/r-cmf60.html

[pula58]

Resistors are definitely 'small' these days. But I would think that by going to metal film, the noise floor will be so much less than it was a few decades ago, when CC resistors were the norm for guitar amps, that you're going to be way ahead of the noise game, regardless of their size. (How's that for a run-on sentence?!) In a nutshell then: MF are known to be very low noise compared to CC. I think you'd be okay with what you've got.

My idea was that I already would be definitely using metal film R's, but that I wanted to step up the size to make secondary noise even lower.

[surfsup]

You have to check the datasheets and look at the size listings.

[roberto]

http://tubedepot.com/r-cmf60.html

11 cents each is not bad.

[ToneMerc]

I used some of these cmf60. About the same size as 1/2 watt, but rated at 500v. Has anyone else tried these?

http://tubedepot.com/r-cmf60.html

Yes, although not in high voltage areas like plate feeds.

TM

[JazzGuitarGimp]

Resistors are definitely 'small' these days. But I would think that by going to metal film, the noise floor will be so much less than it was a few decades ago, when CC resistors were the norm for guitar amps, that you're going to be way ahead of the noise game, regardless of their size. (How's that for a run-on sentence?!) In a nutshell then: MF are known to be very low noise compared to CC. I think you'd be okay with what you've got.

My idea was that I already would be definitely using metal film R's, but that I wanted to step up the size to make secondary noise even lower.

I guess what I am trying to say is that, from a standpoint of noise, you are already 99% of the way there, and it looks to me like you could easily spin your wheels in an academic effort to attain the last 1%. I can understand wanting to go to larger resistors, but not for the same reason; for me, the larger resistors are more mechanically sound - less fragile.

[pdf64]

not in high voltage areas like plate feeds

Why not; a 500V rating should be sufficient for almost all tube amp applications, even taking account of momentary conditions, eg switch on?
Pete