Toroid core with circular cross-section

[ricko_uk]

Hi,
most toroids are rectangula cross-section with rounded corners. But I am looking for toroids (just the cores) with perfectly circular cross-section like this one https://www.hificollective.co.uk/sites/default/files/jantzen-c-coil-inductor-datasheet.pdf

Apart from that Jantzen manufacturer, where can I source them from?

Do they have some standard names or identifying code?

Thank you

[jonpaul]

Bonjour ricko_uk:

The Jantzen part is a woofer crossover inductor, for use 1kHz< with  few details re the core. The Jantzen spec is focused on the wire and other "features" of this "high end" inductor.


1/ Q   Your motivation  for round CX sec of the core?

2/ Q   Specific type of magnetic material required, eg ferrite, transformer steel, powdered iron?


If you have the motivation, you can test with any off the shelf crossover inductor (eg aircore) of similar L and R, and just LISTEN to the audio.

I believe that the costly Jantzen "high end" inductor  will not sound any different than any stock part.

This viewpoint is from an  electrical engineer, and not an "audiophile".

Enjoy,


Jon

[ricko_uk]

Thank you Jon,

1/ Q   Your motivation  for round CX sec of the core?

2/ Q   Specific type of magnetic material required, eg ferrite, transformer steel, powdered iron?

1) it is not for audio application but to test an idea for a measuring instrument.

2) in order of preference: powdered iron, ferrite, transformer steel.

Do you know other places/manufacturers where I can source them from?

Thank you

[jonpaul]

Rebonjour ricko_uk

The design of an inductor or transformer includes the power level, frequency ranges, voltages currents etc.

After these requirements are determined by the particular application, the choice of core shape, wire, bobbin (if any) winding and wore layout can begin. Thus is part of magnetics design.

Thus your note ... in order of preference: powdered iron, ferrite, transformer steel.... reveals that more work is needed to specify exactly what you seek to accomplish.

For shapes, instead of toroids,  ferrite UU, EI and EE cores are all available with round center legs.

Toroids all have chamfered rect or square CX sec for ease of molding and winding. The Jantzen part may have such a core CX but it is covered in tape, shield, etc.

Core vendors

Ferrite: TDK, EPCOS, Tayen Yudo, Nippon Ceramic, Fair Rite

Powdered iron: Micrometals

Transformer steel: Arnold Magnetics, Magnetics inc,

I suggest you research more deeply you specifications, the field of magnetcs design and the vendor catalogs, then proceed.

You will learn a lot.

Bon Chance,

Jon

[ricko_uk]

Thank you again Jon!

The application is an experimental setup. Not for audio, not a transformer or anything toroids/ferrites are commonly used for.

That is why I was listing the materials preferences rather than other specs.

But useful vendors list. Some of them I didn't know.

It doesn't look like any of them do toroids with perfectly circular cross section.

Thank you again!

[ciccio]

Circular  wound metal cores are used in R-core power transformers.  http://jamestransformer.com/en/transformer/R_core_transformer.html

Best regards

[Terry Bites]

 ancient history maybe   https://news.thomasnet.com/fullstory/power-transformer-core-has-circular-cross-section-12168

[Just_another_Dave]

Thank you again Jon!

The application is an experimental setup. Not for audio, not a transformer or anything toroids/ferrites are commonly used for.

That is why I was listing the materials preferences rather than other specs.

But useful vendors list. Some of them I didn't know.

It doesn't look like any of them do toroids with perfectly circular cross section.

Thank you again!

If you’re going to produce a significant amount of devices, some core manufacturers make custom cores (even for experimental setups, as long as the final production is guaranteed to be done by them)

[mazurov]

How close to circular is acceptable? Check Amidon FT-23-W -> https://www.amidoncorp.com/ft-23-w/