Affordable non-magnetic resistors

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All resistors are nonmagnetic, except some special types.

Sorry, completely wrong.

Most resistors ARE magnetic, because they have steel leads, and even if they have copper leads, they still have steel end caps that join the wires to the resistive element. The test is to use a very strong magnet and see if you can move, or even pick up the resistor.

A very few modern resistors are non magnetic, one being the original HOLCOs, but the easiest to get these days are the Dale/VISHEY brown ones, don't remember the number - but we buy them from www.Schuro.de.
They are about 0.50 each, and are well worth it.

Regards, Allen
 
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Try Dale RN-60s, the mil-spec versions that you can get at Mouser. I've used a magnet on several resistors, including some old Roderstein's and Holco's (well, from early 1990) and they move right to the magnet.

I've had CMF55's move under the magnet, but I can't recall an RN60 or above moving at all.
 
I just stuck one of those fast to a magnet. The leads are copper but the end caps are clearly steel.

http://www.hifituning24.de/downloads/cmf55ind.pdf clearly states that they are non-magnetic.

Then if you read the man's original home pages at schuro.de it will tell you that he comissioned a non-magnetic version of this resistor from Vishay. This is after he found that most but not all of the previous resistors he got from Vishay were magnetic. He's been selling these for quite a few years.

P.S. I have some magnetic Roederstein MK3 and built simple voltage dividers of both the non-magnetic CMF55 and the magnetic MK3s then hooked up my CD player to my power amp via the voltage divider. I "believe" the Roedersteins have slightly more resolution and crisper highs than the Vishays but the difference is small and I may be deluding myself.
 
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CMF55 from Schuro is non magnetic, but it gets too expensive these days, even it is 0.1%.
I have switched to PRPs 1% since, which is also non magnetic.

For general purpose, I use Beyschlag MBB0207 from Buerklin :
https://www.buerklin.com/default.asp?srch=E070900&l=e

If you are prepared to pay for CMF55 from Shuro, you might as well go for MK132 from Mouser.


Just my opinion,
Patrick
 

Not unless they also (like Schuro) have ordered non magnetic ones, they are just normal magnetic Rs with steel endcaps and no spec for the wire leads.

Very good Rs, being available in very tight tolerances, but still magnetic.

There is no mention of a non magnetic version in that data sheet, just that the terminations can be chosen by the orderer, but no options listed.

We have a small but VERY powerful neodyndeum (spelling?) magnet that will lift any R off the bench top, but these ones from Schuro are imperevious to it.

We built two exactly the same SACD player Upgrade analong boards, one with our regular metal film Rs, and another with the Schuro Rs, and the sonic difference was very noticable. We now use them everywhere. Just wish we could get big ones as well.

Regards, Allen
 
Try Dale RN-60s, the mil-spec versions that you can get at Mouser. I've used a magnet on several resistors, including some old Roderstein's and Holco's (well, from early 1990) and they move right to the magnet.

I've had CMF55's move under the magnet, but I can't recall an RN60 or above moving at all.

Does it include RN65?

Sorry, completely wrong.

Most resistors ARE magnetic, because they have steel leads, and even if they have copper leads, they still have steel end caps that join the wires to the resistive element. The test is to use a very strong magnet and see if you can move, or even pick up the resistor.

A very few modern resistors are non magnetic, one being the original HOLCOs, but the easiest to get these days are the Dale/VISHEY brown ones, don't remember the number - but we buy them from Schuro - Elektronik, Lautsprecherbau, High End-Audiotechnik.
They are about 0.50 each, and are well worth it.

Regards, Allen

It looks like Schuro don't ship outside of Europe.

CMF55 from Schuro is non magnetic, but it gets too expensive these days, even it is 0.1%.
I have switched to PRPs 1% since, which is also non magnetic.

For general purpose, I use Beyschlag MBB0207 from Buerklin :
Elektronikbauteile online kaufen | Burklin Elektronik | Burklin Elektronik

If you are prepared to pay for CMF55 from Shuro, you might as well go for MK132 from Mouser.


Just my opinion,
Patrick

I didn't find Caddock MK132 on Mouser.

Takman are non-magnetic. Not THAT expensive (1/4W are 0.65 USD). And are VERY suitable for point to point wiring because of the thick copper leads. (At least the 1W jobbies)

Where can I buy them from?

welwyn Resistors for Medical Applications "Non-magnetic resistors for MRI scanners."

Vishay’s New PNM Series of Precision Non-Magnetic Thin Film Resistors "non-magnetic materials to eliminate the effects of stray magnetic fields on circuit performance, resulting in simplified shielding requirements and improved sound quality for these applications."

Regards
James

Where can I buy them from?
 
Hifituning24 is the online shop for Schuro.
They ship outside Europe if your order is large enough.


For one, their website is in German, which I cannot read.
Second, they don't accept credit cards, only bank transfer, which is very expansive.
Also, I doubt if the few resistors I need is "large enough" order.




Those are 1K. I didn't find at Mouser MK132 for most values I need.
 
I have used Takman with good results after making sure they have no magnetic properties. In fact I just used a very strong magnet to be sure. PRP is another line that is non-magnetic per my verification. Michael Percy carries various types and values of Caddock. Takman and PRP are available through Sonic Craft. I have found many vintage resistors found on ebay in lots are non-magnetic. These were made in the 50's and 60's. I have also had very good results with high wattage military grade wirewound Welwyn also bought in lots through ebay. These have visible brass end caps and sizable black bodies--great as plate resistors. I don't believe these are made anymore.
 
PRP resistors are priced reasonably ($0.65 each for 1Watt and $0.5 each for 1/4Watt), while Caddock are very expansive.

All other things being equal bigger resistors "should" sound better. May I suggest the 1W for critical positions even if you do not need the dissipation. PRP appear to be Charles Hansen's favourite low cost resistors, btw.
 
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