Beyerdynamic TR/BV35799 for DI Passive

[user 54307]

Hey!

Hope you doing fine. First post. Im from Costa Rica.

I wanted a little input about a transformer option I have for making a Passive DI Box.

The option is a Beyerdynamic TR/BV35799

The specs i got are:
The pri/sec DCR measures 75 ohms / 1,6 kohms.
voltage ratio is 5:1.

http://www.gyraf.dk/schematics/Beyer_1969.pdf

Hope you can help me with your input, i want to make something like the DI Ferrite from DYIRecordingEquipment or maybe a BO HANSEN.

Greetings

 

[mat_432]

Hello Stefano,

i just saw your post and i'm in the exact same situation.
i also have a Beyer BV/35799 transformer and i would like to use it in a DIY passive DI like the model you mentioned.

So i wonder if you had an advancement on your project and if so, if you would share it with me .

regards,
mat

 

[RuudNL]

I would never use this transformer for a passive DI.
Even if you terminate the transfomer with 1 K.ohms, the reflected input impedance will be around 25 K.ohm.
This is way too low!
What you want is something like 250 K.ohms minimum, the higher the better. But you could use it in an active DI.