Aleph 2 source resistor comparison?

[tomchaoda]

In planning of the Aleph 2, I saw two types of source resistor being used. The Dale Rs-2B Silicone Wirewound resistor is commonly used, and I also saw some use the Fukujima (?) Ceramic Wirewound resistor. The difference is that Ceramic one is non-inductive. (Dale also has the NS serice, non-inductive one, but are too expensive!)

I have attached the photo of the two. I am just wondering if anyone know the sound quality difference of using these two types?

Thomas

[OliverD]

From my experience I would generally avoid wire-wound resistors in audio.

The MPC type resistors in the photo are metal band, not wire-wound. They are commonly used in all kind of audio equipment from consumer to high end. They are cheap and perform pretty good.

If you want something even better, you can parallel some metal oxide resistors or use Isabellenhuette precision power resistors (originally intended to be used as shunts in instruments):

[dieringe]

I used the white ones in an Aleph 30. They are not wound it is a single metal band, so they are "non-inductive". Expensive, 2 euros a piece AFAIR. I switched to much cheaper ones in the aleph-x, also non-wound, but looking like ordinary 2W-resistors with colorcode...
My -X sounds much better than the 30, so I think it's no problem.


m.

[tomchaoda]

I checked further on the net and the white one is MPC71 ceramic metal plate resistor. You can find it here:

http://www.fu-futaba.co.jp/product.html

I believe it is designed basically for the power safety side. I saw some discussion in diyaudio, but none metioned about it's sound quality compare to the Dale Silicone Wirewound, or similar one...

Any one has used it before? Is the sounding good?

Thomas

[wuffwaff]

Thomas,

I use the MCP71 in my Aleph 5. The only problem I see is that they are 10% tollerance so you have to buy a few more to even things out.
Can´t comment on the sound as I haven´t tried other ones.

For my X I will use ordinary 0,25watt metalfilms paralleled.

William

[kilowattski]

Thats alot of resistors. Are you saying for the 1 ohm CSS and Gain Stage resistors, each will be made up of twenty, 0.25 watt resistors each and the four, 3 watt output resistors made of 12 resistors each? It is cost savings you are after? It just seems that 3 watt and 5 watt metal oxide resistors would be easier.

[wuffwaff]

kilowattski,

if you look at the actual wattage you need you don´t need twelfe resistors. For example Aleph X, 8A total bias, 12 fets, 0,5Ohm source resistors.
8/6=1.33A / Fet. P = 1.33x1.33.0.5 = 0,88 watt. This can be done with 6 x 0.25 watt or 3 of the slightly bigger 0,5 watt resistors.

The cost would be less than for the MCP71 resistors, precision would be far better, and induction would also be zero. They would even need less space

William

[kilowattski]

I simply based my data on what is called out for on the schematics.

[jh6you]

Money:

I think it is mostly upon the money I have. Enough money? Why not the resistor@10$? No money? Why not metal oxide resistors? If I think about the sound, I use any. And, just for fun, I arrange the parallel resistors in such a way that all have the same color code order. The same direction.

[tomchaoda]

I already the some of the MPC71 for the source resistors, but some say it is very good sound (as one Japanese Audio Editor greatly recommeded), but I also saw some don't like it!

Personally I used Dale RS-2B wirewound on my Aleph 5 and they are good. To buy more for my Aleph 2 or Aleph X, it cost about USD$1.2+. If the sound is not that much difference, I rather save some of my money....

Apparently, there may have some trade off based on different parts used. The reason I asked is if there is any viewpoint here, then I can make my on view whether to use it or not?

wuffwaff:

on Aleph 5, how's the sound, in general? I happened to have Aleph 5 using the Dale one and they are really good?

Thanks,

Thomas