Ribbon Mic Transformer Permeability

[tomerttb]

Hi,
I'm currently in the process of learning and designing a ribbon microphone transformer, and I have a few questions related to permeability.

1. Permeability Value:
   • Is there a recommended or commonly used permeability value for ribbon microphone transformers?
   • If so, could you provide a suggested range or value to guide my design process?
2. Core Materials and Permeability:
   • Does the choice of core material impact the desired permeability value?
   • For instance, if I opt for Amorphous metal as the core material, should the permeability be within a specific range (let's say, X)?
   • Similarly, if Nickel is chosen as the core material, is there a different recommended permeability value (Y)?

Any insights or guidance you can offer would be great.

Thanks

 

[CJ]

80% NI, aka Supermalloy,

not sure about the amorphous stuff,

 

[Marik]

For ribbon transformers you'd want the permeability as high as it is possible, so for given inductance you get less turns=lower winding DCR=lower Noise and higher output... and we want to squeeze out every last dB of that. A ribbon wound toroidal core is the most efficient and doesn't have an air gap. Amorphous materials permeability is quite a bit higher than 80% Ni. The good thing here because of very low signal you don't have to worry about overloading. So the Amorphous ribbon wound toroidal core it is. If stuck with 80%Ni at least make it UI, use as thick as possible Pri wire you can fit.

 

[CJ]

Marik, you have any new piano jams you could post?

 

[Marik]

Marik, you have any new piano jams you could post?

Sorry for OT, but since CJ asked





Best, M

 

[CJ]

Wow that was frickin incredible Marik! Completely awesome!
Tendons of steel, thank you!
For a moment there I thought you had posted an Igor Stravinsky video. (neoclassical period of course)

 

[Marik]

Wow that was frickin incredible Marik! Completely awesome!
Tendons of steel, thank you!
For a moment there I thought you had posted an Igor Stravinsky video. (neoclassical period of course)

Thank you, CJ!

And yes, I play Stravinsky too. Concerto for piano and woodwinds, Tango, Petrushka, as well as with violin Chanson Russe, Dance Russe, and Divirtimento.

Best, M

 

[gyraf]

Thanks for those, Mark - it's been a while since I enjoyed the piano this much

/Jakob E.

 

[klem]

@Marik do you happen to know what mics (yours?) were used for the audio feed for these great performances?
BTW, the proverbial check is in the mail...

 

[CJ]

Yeah I would buy a cd for sure,

Nice sounding piano,