Transformer choice for preamp module

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JaschaD

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Nov 7, 2022
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Hi,
I do have a Swiss Autophon microphone preamp module which I quite like. It does have a Beyerdynamic "peanut" mic input transformer.

Now I have to other amplifier modules that are exactly the same as the mic preamp, only that they don t have the input transformer. And I adding transformers on them.

Now the input transformer has a ratio of 1:15. My question would be, could I possibly buy similar Beyerdynamic transformers, but with another ratio (1:5 for example)?

Or even buy other transformers (studer, sony, carnhill), and what parameters would I have to pay attention to?

One thing is that the preamp module tend to distort a bit when close mic'ing. Thus would a transformer with a lower ratio do even some improvement for that?

Any help would be greatly appreciated.
 

dmp

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Now the input transformer has a ratio of 1:15. My question would be, could I possibly buy similar Beyerdynamic transformers, but with another ratio (1:5 for example)?
For sure -They made them in a lot of ratios (1, 3.16, 5, 7, 10, 15, 20)
They are on ebay regularly and I see 1:5 regularly.
If you look up the catalog, you can decifer the part numbers

One thing is that the preamp module tend to distort a bit when close mic'ing. Thus would a transformer with a lower ratio do even some improvement for that?
You have to figure out if the distortion is from the transformer saturating, or from the electronics. The Beyers do sound amazing ,but cannot take as high a level as others. If you have another transformer to compare with, swap and see if the distortion goes away. If the 1:15 step up is sending a level high enough that you have some clipping in the amp stages, maybe put a pad before the transformer?
The transformer ratio is often determined to minimize noise performance. The headroom (before clipping / distortion) should not require a different transformer.
 

abbey road d enfer

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Or even buy other transformers (studer,
Most Studer xfmrs came from the same manufacturer as Beyer.
One thing is that the preamp module tend to distort a bit when close mic'ing. Thus would a transformer with a lower ratio do even some improvement for that?
You could probably decrease gain electronically.
 
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