What's the "milk choclate colour" plate resistors

[Svempan]

Hi,

I wonder about the light brown "milk chocolate colour" plate resistors that many people use in their Dumble inspired amps and as it seems HAD himself used. See picture:

What kind of resistors are they?

And most important, what do they do for the sound. What’s the difference in sound with these or with carbon comps, metal films or carbon films?

Thank you,

Svempan

[heisthl]

Those are the VD resistors everyone talks about (and should be using) for V1 and V2 plates. (VD=Vishay Dale RN65 series).

[Luthierwnc]

I don't know who your best local vendor might be but here is a link to a stateside supplier:

http://www.mouser.com/catalog/632/545.pdf

You want the 1/2 watt ones.

Cheers, Skip

[Svempan]

Thanks for the answers.

OK it's precision metal film resistors.

I live in Sweden... Maybe my best local vendor is to buy where you buy...

My main question, though, is still: What do they do for the sound? What's the difference in sound with these or with, for example, more conventional 2W metal film resistors (Phoenix PR02)?
[img:400:48]http://www.elfa.se/images/highres/h5452.jpg[/img]

I use these a lot in my amp repair shop.

Thank you!

[dogears]

I have heard of lots of failures with those small PR series from a couple major builders. I also think they are more like a metal oxide. They are really small!! If they are metal film (I know they are advertised as film) , they are totally different than what we know as metal film. I would stick with the RN series. As a baseline since it was the standard.

Thanks for the answers.

OK it's precision metal film resistors.

I live in Sweden... Maybe my best local vendor is to buy where you buy...

My main question, though, is still: What do they do for the sound? What's the difference in sound with these or with, for example, more conventional 2W metal film resistors (Phoenix PR02)?
[img:400:48]http://www.elfa.se/images/highres/h5452.jpg[/img]

I use these a lot in my amp repair shop.

Thank you!

[glasman]

Do not be surprised if you can not find the Vishay Dales in Europe. The RN65's are not RoHS compatible.

[Svempan]

I have heard of lots of failures with those small PR series from a couple major builders. I also think they are more like a metal oxide. They are really small!! If they are metal film (I know they are advertised as film) , they are totally different than what we know as metal film. I would stick with the RN series. As a baseline since it was the standard.

The resitors I speak of are, for what I know, metal film, are 2 W and are in the size of a carbon comp 1/2 W.

I have used them for many years with good results. Booth soundwise and no-failure-wise.

If there are differences in what we know as metal films in Europe than you do in America, I will be very surprised.

I see your piont when you say that it's best to "stick with the RN series", but maybe I have to do my own sound test.

[dogears]

The PR01 are the ones I have tried, and the ones that have opened in service. I know Andy Fuchs had failures using them as plate loads.

They are really small..... No? The 1w is only 6.5mmX8.5mm.

The 2W is 10mmX12mm

I have heard of lots of failures with those small PR series from a couple major builders. I also think they are more like a metal oxide. They are really small!! If they are metal film (I know they are advertised as film) , they are totally different than what we know as metal film. I would stick with the RN series. As a baseline since it was the standard.

The resitors I speak of are, for what I know, metal film, are 2 W and are in the size of a carbon comp 1/2 W.

I have used them for many years with good results. Booth soundwise and no-failure-wise.

If there are differences in what we know as metal films in Europe than you do in America, I will be very surprised.

I see your piont when you say that it's best to "stick with the RN series", but maybe I have to do my own sound test.

[Funkalicousgroove]

Stay away from those phoenix resistors, but really any good quality Metal film should be fine.

[VacuumVoodoo]

Phoenix are made in Brazil, at least the ones sold in EU. Look at the date codes: if they're made during the Carnival season refuse to accept delivery.
Anything manufactured between April and September is ok.

No. I'm not bashing Brazil or Brazilians; I've had my best times there.